Exposure to Agent Orange is associated with increased recurrence after surgical treatment of stage I non-small cell lung cancer

OBJECTIVE

Approximately 3 million Americans served in the armed forces during the Vietnam War. Veterans have a higher incidence rate of lung cancer compared with the general population, which may be related to exposures sustained during service. Agent Orange, one of the tactical herbicides used by the armed forces as a means of destroying crops and clearing vegetation, has been linked to the development of several cancers including non-small cell lung cancer. However, traditional risk models of lung cancer survival and recurrence often do not include such exposures. We aimed to examine the relationship between Agent Orange exposure and overall survival and disease recurrence for surgically treated stage I non-small cell lung cancer.

METHODS

We performed a retrospective cohort study using a uniquely compiled dataset of US Veterans with pathologic I non-small cell lung cancer. We included adult patients who served in the Vietnam War and underwent surgical resection between 2010 and 2016. Our 2 comparison groups included those with identified Agent Orange exposure and those who were unexposed. We used multivariable Cox proportional hazards and Fine and Gray competing risk analyses to examine overall survival and disease recurrence for patients with pathologic stage I disease, respectively.

RESULTS

A total of 3958 Vietnam Veterans with pathologic stage I disease were identified (994 who had Agent Orange exposure and 2964 who were unexposed). Those who had Agent Orange exposure were more likely to be male, to be White, and to live a further distance from their treatment facility (P < .05). Tumor size distribution, grade, and histology were similar between cohorts. Multivariable Cox proportional hazards modeling identified similar overall survival between cohorts (Agent Orange exposure hazard ratio, 0.97; 95% CI, 0.86-1.09). Patients who had Agent Orange exposure had a 19% increased risk of disease recurrence (hazard ratio, 1.19; 95% CI, 1.02-1.40).

CONCLUSIONS

Veterans with known Agent Orange exposure who undergo surgical treatment for stage I non-small cell lung cancer have an approximately 20% increased risk of disease recurrence compared with their nonexposed counterparts. Agent Orange exposure should be taken into consideration when determining treatment and surveillance regimens for Veteran patients.

Hospitalizations Among Veterans Treated for Metastatic Prostate Cancer With Abiraterone or Enzalutamide

BACKGROUND

Abiraterone and enzalutamide are second generation androgen receptor pathway inhibitors (ARPIs) used to treat advanced or metastatic prostate cancer. Without head-to-head comparative studies identifying 1 agent as preferred initial therapy, physician preferences guide initial ARPI choice. This study compares hospitalizations among patients treated initially with abiraterone versus enzalutamide.

PATIENTS AND METHODS

United States veterans treated with abiraterone or enzalutamide between May 13, 2011 and December 31, 2019; then compared hospitalization rate during first treatment with ARPI in the Veterans Healthcare Administration. Baseline incidence rate of hospitalization was determined from data 1 year prior to ARPI. Incidence Rate Difference (IRD) was calculated using χ2 test and difference in IRD using Poisson Regression.

RESULTS

19,775 veterans were identified; 13,527 (68.4%) were initially treated with abiraterone and 6248 (31.6%) initially with enzalutamide. The enzalutamide cohort was older (75.8 vs. 74.5 years, P < .001) and had higher baseline comorbidities at ARPI initiation (4.4 vs. 4.0, P < .001). Patients were treated with enzalutamide longer than abiraterone (median 9.0 vs. 8.0 months, P < .001). Total hospitalizations increased from 465 per 1000 person-years in the year prior to treatment with abiraterone to 567 during treatment. Total hospitalizations increased from 417 per 1000 person-years in the year prior to treatment with enzalutamide to 430 during treatment. Total rate of hospitalization increased 22% for abiraterone compared to a 3% increase for enzalutamide in the 12 months after ARPI initiation (P < .0001). Abiraterone was associated with greater increase in rates of acute heart failure, atrial fibrillation, acute kidney injury, urinary tract infections, sepsis, and pneumonia.

CONCLUSION

By comparing the rate of hospitalization before vs. during treatment, real world analyses identified a 22% versus 3% increase in hospitalizations with abiraterone compared to enzalutamide respectively, despite being used in a younger population with less comorbid disease. Abiraterone was also associated with higher risk of infections, a novel finding.

Survival in Patients With De Novo Metastatic Prostate Cancer

This cross-sectional study investigates trends in overall survival among patients with newly diagnosed metastatic prostate cancer in 2 national registries in the United States.

Effect of BMI and hemoglobin A1c on survival of veterans with metastatic castration-resistant prostate cancer treated with abiraterone or enzalutamide

BACKGROUND

Abiraterone acetate and enzalutamide are two common therapies for metastatic castration-resistant prostate cancer (mCRPC) that have shown improved overall survival (OS). The drugs have different mechanisms of action with limited comparative trials to evaluate treatment in patients with comorbidities such as obesity and diabetes. This is important since abiraterone requires the co-administration of prednisone. We assessed the relationship between body mass index (BMI), hemoglobin A1c (HbA1c), treatment, and survival in mCRPC.

METHODS

Veterans treated with abiraterone or enzalutamide within the Veterans Health Administration between September 10, 2014 and June 2, 2017 with BMI and HbA1c were identified. Additional variables included age, baseline prostate-specific antigen at first treatment for mCRPC, race, and the Charlson comorbidity index. Differences in survival were compared using the Kaplan-Meier method. Cox proportional hazards regression modeling was used to assess the association between initial treatment, BMI, and HbA1c while adjusting for confounding variables.

RESULTS

A total of 5231 patients were identified with a mean age of 75.2 years and 1241 (23.7%) were of black race. BMI was associated with OS with longest median survival of 29.8 months in BMI ≥ 30 (n = 1903), 23.9 months in BMI 25-30 (n = 1879), 15.9 months in BMI 18.5-25 (n = 1336), and 9.2 months in BMI < 18.5 (n = 113, p < 0.001). In a multivariable model compared to normal BMI, increased mortality was observed in BMI < 18.5 (adjusted hazard ratio (aHR) = 1.583, 95% confidence interval [CI]: 1.29-1.94) and a decreased mortality in BMI 25-30 (aHR = 0.751, 95% CI: 0.69-0.81) and BMI > 30 (aHR = 0.644, 95% CI: 0.59-0.70). In 3761 patients with BMI > 25, there was longer OS in patients treated with enzalutamide (28.4 months, n = 1615) compared to abiraterone (25.8 months, n = 2146, p = 0.002). In 1470 patients with BMI < 25, there was no difference in OS between patients treated with enzalutamide (16.0 months, n = 597, p = 0.513) or abiraterone (16.1 months, n = 873). In 1333 veterans with HbA1c ≥ 6.5%, initial prescription of enzalutamide was associated with longer OS compared with abiraterone (24.4 vs. 20.5 months, p = 0.0005). In 2088 patients with HbA1c < 6.5%, there was no difference in OS in patients who were initially prescribed enzalutamide versus abiraterone (25.7 vs. 23.5 months, p = 0.334).

CONCLUSIONS

In veterans with mCRPC, increased BMI was associated with longer survival. Veterans with BMI > 25 had longer survival with enzalutamide compared to abiraterone. In patients with HbA1c ≥ 6.5%, enzalutamide was associated with longer survival compared to abiraterone. These results may facilitate prognostication of survival and improve treatment selection based on patient comorbidities.

Lobe-specific lymph node sampling is associated with lower risk of cancer recurrence

Objective

Adequate intraoperative lymph node (LN) assessment is a critical component of early-stage non-small cell lung cancer (NSCLC) resection. The National Comprehensive Cancer Network and the American College of Surgeons Commission on Cancer (CoC) recommend station-based sampling minimums agnostic to tumor location. Other institutions advocate for lobe-specific LN sampling strategies that consider the anatomic likelihood of LN metastases. We examined the relationship between lobe-specific LN assessment and long-term outcomes using a robust, highly curated cohort of stage I NSCLC patients.

Methods

We performed a cohort study using a uniquely compiled dataset from the Veterans Health Administration and manually abstracted data from operative and pathology reports for patients with clinical stage I NSCLC (2006-2016). For simplicity in comparison, we included patients who had right upper lobe (RUL) or left upper lobe (LUL) tumors. Based on modified European Society of Thoracic Surgeons guidelines, lobe-specific sampling was defined for RUL tumors (stations 2, 4, 7, and 10 or 11) and LUL tumors (stations 5 or 6, 7, and 10 or 11). Our primary outcome was the risk of cancer recurrence, as assessed by Fine and Gray competing risks modeling. Secondary outcomes included overall survival (OS) and pathologic upstaging. Analyses were adjusted for relevant patient, disease, and treatment variables.

Results

Our study included 3534 patients with RUL tumors and 2667 patients with LUL tumors. Of these, 277 patients (7.8%) with RUL tumors and 621 patients (23.2%) with LUL tumors met lobe-specific assessment criteria. Comparatively, 34.7% of patients met the criteria for count-based assessment, and 25.8% met the criteria for station-based sampling (ie, any 3 N2 stations and 1 N1 station). Adherence to lobe-specific assessment was associated with lower cumulative incidence of recurrence (adjusted hazard ratio [aHR], 0.83; 95% confidence interval [CI], 0.70-0.98) and a higher likelihood of pathologic upstaging (aHR, 1.49; 95% CI, 1.20-1.86). Lobe-specific assessment was not associated with OS.

Conclusions

Adherence to intraoperative LN sampling guidelines is low. Lobe-specific assessment is associated with superior outcomes in early-stage NSCLC. Quality metrics that assess adherence to intraoperative LN sampling, such as the CoC Operative Standards manual, also should consider lobe-specific criteria.

Inhaled medications for chronic obstructive pulmonary disease predict surgical complications and survival in stage I non-small cell lung cancer

Background

Lung function is routinely assessed prior to surgical resection for non-small cell lung cancer (NSCLC). Further assessment of chronic obstructive pulmonary disease (COPD) using inhaled COPD medications to determine disease severity, a readily available metric of disease burden, may predict postoperative outcomes and overall survival (OS) in lung cancer patients undergoing surgery.

Methods

We retrospectively evaluated clinical stage I NSCLC patients receiving surgical treatment within the Veterans Health Administration from 2006-2016 to determine the relationship between number and type of inhaled COPD medications (short- and long-acting beta2-agonists, muscarinic antagonists, or corticosteroids prescribed within 1 year before surgery) and postoperative outcomes including OS using multivariable models. We also assessed the relationship between inhaled COPD medications, disease severity [measured by forced expiratory volume in 1 second (FEV1)], and diagnosis of COPD.

Results

Among 9,741 veterans undergoing surgery for clinical stage I NSCLC, patients with COPD were more likely to be prescribed inhaled medications than those without COPD [odds ratio (OR) =5.367, 95% confidence interval (CI): 4.886-5.896]. Increased severity of COPD was associated with increased number of prescribed inhaled COPD medications (P<0.0001). The number of inhaled COPD medications was associated with prolonged hospital stay [adjusted OR (aOR) =1.119, 95% CI: 1.076-1.165), more major complications (aOR =1.117, 95% CI: 1.074-1.163), increased 90-day mortality (aOR =1.088, 95% CI: 1.013-1.170), and decreased OS [adjusted hazard ratio (aHR) =1.061, 95% CI: 1.042-1.080]. In patients with FEV1 ≥80% predicted, greater number of prescribed inhaled COPD medications was associated with increased 30-day mortality (aOR =1.265, 95% CI: 1.062-1.505), prolonged hospital stay (aOR =1.130, 95% CI: 1.051-1.216), more major complications (aOR =1.147, 95% CI: 1.064-1.235), and decreased OS (aHR =1.058, 95% CI: 1.022-1.095). When adjusting for other drug classes and covariables, short-acting beta2-agonists were associated with increased 90-day mortality (aOR =1.527, 95% CI: 1.120-2.083) and decreased OS (aHR =1.087, 95% CI: 1.005-1.177).

Conclusions

In patients with early-stage NSCLC, inhaled COPD medications prescribed prior to surgery were associated with both short- and long-term outcomes, including in patients with FEV1 ≥80% predicted. Routine assessment of COPD medications may be a simple method to quantify operative risk in early-stage NSCLC patients.

Survival of veterans treated with enzalutamide and abiraterone for metastatic castrate resistant prostate cancer based on comorbid diseases

BACKGROUND

Comorbid diseases influence patient outcomes, yet little is known about how comorbidities interact with treatments for metastatic castrate-resistant prostate cancer (mCRPC). No head-to-head trials have compared the efficacy of abiraterone and enzalutamide - oral androgen-receptor targeted agents (ARTAs) for mCRPC. In patients with comorbid disease, outcomes with ARTAs may differ due to disparate mechanisms of action, adverse events, and drug interactions.

METHODS

Retrospective observational study of US veterans initiating treatment for mCRPC with abiraterone or enzalutamide between September 2014 and June 2017. Treatment duration and overall survival (OS) was compared based on age and comorbid diseases. The association between ARTA and OS was assessed using Cox proportional hazards and propensity-score matched modeling while adjusting for potential confounders. Sensitivity analyses were performed based on patient age, comorbidities, and subsequent treatments for mCRPC.

RESULTS

Of 5822 veterans treated for mCRPC, 43.0% initially received enzalutamide and 57.0% abiraterone. Veterans initially treated with enzalutamide versus abiraterone were older (mean 75.8 vs. 75.0 years) with higher mean Charlson comorbidity index (4.4 vs. 4.1), and higher rates of cardiovascular disease or diabetes (74.2% vs. 70.6%). In the entire population, veterans initially treated with enzalutamide had longer median OS compared to those initially treated with abiraterone (24.2 vs. 22.1 months, p = 0.001). In veterans with cardiovascular disease or diabetes, median treatment duration with enzalutamide was longer (11.4 vs. 8.6 months, p < 0.001) with longer median OS compared to abiraterone (23.2 vs. 20.5 months, p < 0.001). In a propensity score matched cohort, enzalutamide was associated with decreased mortality compared to abiraterone (HR 0.90, 95% CI 0.84-0.96).

CONCLUSIONS

Veterans with cardiovascular disease or diabetes had longer treatment duration and OS with enzalutamide compared to abiraterone. Further study of ARTA selection may benefit men with metastatic castrate resistant prostate cancer and likely hormone sensitive prostate cancer, especially among patients with comorbid diseases.

Local Treatment and Treatment-Related Adverse Effects Among Patients With Advanced Prostate Cancer

Importance

Recent data suggest that local treatment with radical prostatectomy or radiation may improve survival outcomes in men with advanced prostate cancer. However, evidence is lacking on treatment-related adverse effects among men with advanced prostate cancer.

Objective

To assess the association of local treatment on treatment-related adverse effects among men diagnosed with advanced prostate cancer.

Design, Setting, and Participants

This cohort study assessed men diagnosed with advanced prostate cancer (defined as T4, N1, and/or M1 prostate cancer) between January 1, 1999, and December 31, 2013, with follow-up through December 31, 2021, who were treated at Veterans Health Administration medical centers.

Exposure

Local treatment with radical prostatectomy or radiation.

Main Outcomes and Measures

Main outcomes were treatment-related adverse effects, including constitutional, gastrointestinal, pain, sexual function, and urinary function conditions, at 3 intervals after initial treatment (≤1 year, >1 to ≤2 years, and >2 to ≤5 years) after initial treatment.

Results

This cohort study consisted of 5502 men (mean [SD] age, 68.7 [10.3] years) diagnosed with advanced prostate cancer. Of the cohort, 1705 men (31.0%) received local treatment. There was a high prevalence of adverse conditions in men receiving both local and nonlocal treatment, and these adverse conditions persisted for more than 2 years to 5 years or less after initial treatment. A total of 916 men (75.2%) with initial local treatment and 897 men (67.1%) with initial nonlocal treatment reported the presence of at least 1 adverse condition for more than 2 years to 5 years or less after initial treatment. In the first year, local treatment (vs nonlocal) was associated with adverse gastrointestinal (multivariable-adjusted odds ratio [AOR], 4.08; 95% CI, 3.06-5.45), pain (AOR, 1.57; 95% CI, 1.35-1.83), sexual (AOR, 2.96; 95% CI, 2.42-3.62), and urinary (AOR, 2.25; 95% CI, 1.90-2.66) conditions. Local treatment (without secondary treatment) remained significantly associated with adverse gastrointestinal (AOR, 2.39; 95% CI, 1.52-3.77), sexual (AOR, 3.36; 95% CI, 2.56-4.41), and urinary (AOR, 1.39; 95% CI, 1.09-1.78) conditions at more than 2 years to 5 years or less after treatment.

Conclusions and Relevance

In this cohort study of men with advanced prostate cancer, local treatment was associated with persistent treatment-related adverse effects across multiple domains. These results suggest that patients and clinicians should consider the adverse effects of local treatment when making treatment decisions in the setting of advanced prostate cancer.

Natural Language Processing-Assisted Classification Models to Confirm Monoclonal Gammopathy of Undetermined Significance and Progression in Veterans' Electronic Health Records

PURPOSE

To develop and validate natural language processing (NLP)-assisted machine learning (ML)-based classification models to confirm diagnoses of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) from electronic health records (EHRs) in the Veterans Health Administration (VHA).

MATERIALS AND METHODS

We developed precompiled lexicons and classification rules as features for the following ML classifiers: logistic regression, random forest, and support vector machines (SVMs). These features were trained on 36,044 EHR documents from a random sample of 400 patients with at least one International Classification of Disease code for MGUS diagnosis from 1999 to 2021. The best-performing feature combination was calibrated in the validation set (17,826 documents/200 patients) and evaluated in the testing set (9,250 documents/100 patients). Model performance in diagnosis confirmation was compared with manual chart review results (gold standard) using recall, precision, accuracy, and F1 score. For patients correctly labeled as disease-positive, the difference between model-identified diagnosis dates and the gold standard was also computed.

RESULTS

In the testing set, the NLP-assisted classification model using SVMs achieved best performance in both MGUS and MM confirmation with recall/precision/accuracy/F1 of 98.8%/93.3%/93.0%/96.0% for MGUS and 100.0%/92.3%/99.0%/96.0% for MM. Dates of diagnoses matched (±45 days) with those of gold standard in 73.0% of model-confirmed MGUS and 84.6% of model-confirmed MM.

CONCLUSION

An NLP-assisted classification model can reliably confirm MGUS and MM diagnoses and dates and extract laboratory results using automated interpretation of EHR data. This algorithm has the potential to be adapted to other disease areas in VHA EHR system.

Development and Validation of the VA Lung Cancer Mortality (VALCAN-M) Score for 90-Day Mortality Following Surgical Treatment of Clinical Stage I Lung Cancer

OBJECTIVE

The aim was to develop and validate the Veterans Administration (VA) Lung Cancer Mortality (VALCAN-M) score, a risk prediction model for 90-day mortality following surgical treatment of clinical stage I nonsmall-cell lung cancer (NSCLC).

BACKGROUND

While surgery remains the preferred treatment for functionally fit patients with early-stage NSCLC, less invasive, nonsurgical treatments have emerged for high-risk patients. Accurate risk prediction models for postoperative mortality may aid surgeons and other providers in optimizing patient-centered treatment plans.

METHODS

We performed a retrospective cohort study using a uniquely compiled VA data set including all Veterans with clinical stage I NSCLC undergoing surgical treatment between 2006 and 2016. Patients were randomly split into derivation and validation cohorts. We derived the VALCAN-M score based on multivariable logistic regression modeling of patient and treatment variables and 90-day mortality.

RESULTS

A total of 9749 patients were included (derivation cohort: n=6825, 70.0%; validation cohort: n=2924, 30.0%). The 90-day mortality rate was 4.0% (n=390). The final multivariable model included 11 factors that were associated with 90-day mortality: age, body mass index, history of heart failure, forced expiratory volume (% predicted), history of peripheral vascular disease, functional status, delayed surgery, American Society of Anesthesiology performance status, tumor histology, extent of resection (lobectomy, wedge, segmentectomy, or pneumonectomy), and surgical approach (minimally invasive or open). The c statistic was 0.739 (95% CI=0.708-0.771) in the derivation cohort.

CONCLUSIONS

The VALCAN-M score uses readily available treatment-related variables to reliably predict 90-day operative mortality. This score can aid surgeons and other providers in objectively discussing operative risk among high-risk patients with clinical stage I NSCLC considering surgery versus other definitive therapies.

Mortality in the US Populations With Monoclonal Gammopathy of Undetermined Significance

This cohort study analyzes a nationally representative sample with a screening test for monoclonal gammopathy of undetermined significance (MGUS) to evaluate overall survival of populations with MGUS compared with those without MGUS among the general population in the US.

Frailty and survival among veterans treated with abiraterone or enzalutamide for metastatic castration-resistant prostate cancer

INTRODUCTION

Abiraterone and enzalutamide are treatments for metastatic castration-resistant prostate cancer (mCRPC). Due to a lack of head-to-head trials, they are prescribed interchangeably. However, the drugs have different pharmacokinetics and thus may have differing efficacy and adverse effects influenced by patient functional status and comorbid diseases. Additionally, mCRPC mainly affects older adults and since the prevalence of frailty increases with age, frailty is an important patient factor to consider in personalizing drug selection.

MATERIALS AND METHODS

We conducted a retrospective observational study of US veterans treated with abiraterone or enzalutamide for mCRPC from September 2014 to June 2017. Frailty was assessed using the Veterans Affairs Frailty Index (VA-FI), which utilizes administrative codes to assign a standardized frailty score. Patients were categorized as frail if VA-FI scores were > 0.2. The primary outcome was difference in overall survival (OS) between the two treatment groups. Cox regression modeling and propensity score matching was used to compare between abiraterone and enzalutamide treatments.

RESULTS

We identified 5,822 veterans, 57% of whom were initially treated with abiraterone and 43% with enzalutamide. Frail patients (n = 2,314; 39.7%) were older, with a mean age of 76.1 versus 74.9 years in the non-frail group (n = 3,508; 60.3%, p < 0.001) and had shorter OS compared to non-frail patients regardless of treatment group (18.5 vs. 26.6 months, p < 0.001). Among non-frail patients there was no significant difference in OS between abiraterone and enzalutamide treatment (27.7 vs 26.1 months, p = 0.07). However, frail patients treated with enzalutamide versus abiraterone had improved OS (20.7 vs 17.2 months, p < 0.001). In a propensity score matched analysis of frail patients (n = 2,070), enzalutamide was associated with greater median OS (24.1 vs 20.9 months, p < 0.001). In patients with dementia, enzalutamide was associated with longer OS (19.4 vs. 16.6 months, p = 0.003).

DISCUSSION

In this study of 5822 US veterans with mCRPC, treatment with enzalutamide was associated with improved OS compared to abiraterone among frail veterans and veterans with dementia, but not among non-frail veterans. Future studies should evaluate interactions between frailty and cancer treatments to optimize selection of therapy among frail adults.

Abstract 6741: Number of prescription drugs and overall survival in metastatic castrate resistant prostate cancer

Background: Assessment of comorbid diseases is essential to clinical research and may risk-stratify patients for adverse events and death. Total number of prescription medications and drug classes could be an easy-to-use tool for estimating patient risk independent of established methods such as the Charlson Comorbidity Index (CCI) that is created from administrative data. Additionally, clinicians have access to prescription medication lists, facilitating assessment of comorbidities in clinical settings.

Methods: Retrospective observational study of US Veterans treated for metastatic castrate resistant prostate cancer in the Veterans Health Administration who received treatment with abiraterone or enzalutamide between May 2011-June 2, 2017. We determined number of unique drugs and anatomic therapeutic chemical (ATC) drug classes prescribed in the year prior up to 14 days before initiation of treatment. Multivariable logistic regression and Cox proportional hazard modeling was used to assess the association between number of drugs with all-cause 90-day mortality and overall survival (OS) while accounting for important covariates including age, CCI, body-mass index, prostate specific antigen, race, prior docetaxel, hemoglobin, albumin, bilirubin, and creatinine.

Results: Among 11,021 Veterans, a median (IQR) of 11 (6,18) unique medications and 10 (5,15) unique ATC medication classes were filled in the year prior to treatment. The median age was 75 years with median CCI of 3 and 2,550 were black (23.1%). Increasing age was associated with increased CCI across age strata with mean CCI of 3.7 in age &lt;70, 4.2 in age 70-79, and 4.3 in age 80+ (p&lt;0.001). Increased age was associated with decreased number of unique medicines with mean 14.7 in age &lt;70, 12.7 in age 70-79, and 11.2 in age 80+ (p&lt;0.001). Black race was associated with increased mean number of medications compared to white race (15.5 vs. 12.0, p&lt;0.001). After adjusting for relevant patient, tumor, and treatment factors, the number of medications and drug classes were each independently associated with increased 90-day mortality with adjusted OR (95% CI) of 1.021 (1.011,1.030) and 1.024 (1.012,1.036) respectively. Both number of medications and number of classes were also associated with decreased OS with adjusted Hazard Ratio of 1.015 (1.013,1.018) and 1.018 (1.014,1.021) respectively. Within subgroups of patients with comparable CCI, increased number of medications was associated with increased risk of death.

Conclusion: The number of prescription medications and drug classes are independently associated with short- and long-term outcomes in patients undergoing treatment for metastatic castrate resistant prostate cancer, even after accounting for important covariates including age and CCI. Assessment of patient medications may provide a simple, yet reliable tool to assess comorbidities, risk of adverse events, and death.

Citation Format: Martin W. Schoen, Carley Pickett, Daniel B. Eaton, Brendan T. Heiden, Su-Hsin Chang, Yan Yan, Melanie P. Subramanian, Varun Puri. Number of prescription drugs and overall survival in metastatic castrate resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6741.

Abstract 734: Comprehensive validation of high-risk clinicopathologic features in early-stage, node-negative non-small cell lung cancer

Objective: Current guidelines recommend adjuvant therapy for patients with completely resected non-small cell lung cancer (NSCLC) with high-risk clinical or pathologic features. Despite this, the relationship between these features and cancer recurrence is poorly elucidated.

Methods: We conducted a retrospective cohort study using a uniquely compiled dataset from the US Veterans Health Administration (VHA) including all Veterans with pathologic early-stage (≤5cm, N0) NSCLC receiving definitive surgical treatment (2010-2016). Based on National Comprehensive Cancer Network guidelines, we evaluated 6 high-risk features: tumor size, tumor grade, visceral-pleural invasion, lymphovascular invasion, non-anatomic wedge resection, and adequacy of nodal sampling. We developed a score reflecting the relationship between these high-risk features and recurrence, using a multivariable competing risk model (death as competing event). The score performance was then tested in an external cohort from the National Cancer Database (NCDB).

Results: The study included 3,799 Veterans. The median follow-up was 7.1 years. Recurrence was detected in 800 (21.1%) patients. The association between high-risk features and cancer recurrence were as follows: tumor size (e.g., 31-40mm vs. 0-10mm, multivariable-adjusted hazard ratio, aHR 1.676, 95% CI 1.229-2.285, p=0.001), tumor grade (e.g., III vs. I, aHR 1.884, 95% CI 1.448-2.449, p&lt;0.001), visceral-pleural invasion (aHR 1.096, 95% CI 0.905-1.329, p=0.35), lymphovascular invasion (aHR 1.747, 95% CI 1.441-2.117, p&lt;0.001), non-anatomic wedge resection (aHR 1.335, 95% CI 1.101-1.619, p=0.003), and adequacy of nodal sampling (e.g., 1-4 lymph nodes vs. ≥10 lymph nodes, aHR 1.392, 95% CI 1.149-1.687, p&lt;0.001). Using these parameters, a score was created reflecting the association between high-risk features and recurrence. The score ranged from 0-36, with higher scores reflecting higher cumulative incidence of recurrence. The score was further divided into low- (0-11, n=1,263, 33.3%; 5-yr recurrence risk 13.0%), moderate- (12-15, n=1,134, 29.9%; 5-yr recurrence risk 19.0%), and high-risk (16-36, n=1,402, 36.9%; 5-yr recurrence risk 27.1%) categories. Higher scores were also associated with diminished overall survival (median OS, low-risk: 9.0 yrs; moderate-risk: 7.3 yrs; high-risk: 5.4 yrs). The score was further tested in a cohort of 63,232 patients from the NCDB and higher scores remained associated with worse overall survival (median OS, low-risk: 9.4 yrs; moderate-risk: 8.0 yrs; high-risk: 6.3 yrs).

Conclusions: High-risk clinicopathologic features are associated with dramatically higher risk of recurrence and worse overall survival. Multivariable assessment of these features using a comprehensive yet pragmatic score may help to standardize adjuvant treatment eligibility following curative intent resection.

Citation Format: Brendan T. Heiden, Daniel B. Eaton, Su-Hsin Chang, Yan Yan, Martin W. Schoen, Bindiya G. Patel, Theodore S. Thomas, Bryan F. Meyers, Benjamin D. Kozower, Varun Puri. Comprehensive validation of high-risk clinicopathologic features in early-stage, node-negative non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 734.

Assessment of Duration of Smoking Cessation Prior to Surgical Treatment of Non-small Cell Lung Cancer

OBJECTIVE

To define the relationship between the duration of smoking cessation and postoperative complications for patients with lung cancer undergoing surgical treatment.

BACKGROUND

Smoking increases the risk of postoperative morbidity and mortality in patients with lung cancer undergoing surgical treatment. Although smoking cessation before surgery can mitigate these risks, the ideal duration of preoperative smoking cessation remains unclear.

METHODS

Using a uniquely compiled Veterans Health Administration dataset, we performed a retrospective cohort study of patients with clinical stage I non-small cell lung cancer undergoing surgical treatment between 2006 and 2016. We characterized the relationship between duration of preoperative smoking cessation and risk of postoperative complications or mortality within 30-days using multivariable restricted cubic spline functions.

RESULTS

The study included a total of 9509 patients, of whom 6168 (64.9%) were smoking at the time of lung cancer diagnosis. Among them, only 662 (10.7%) patients stopped smoking prior to surgery. Longer duration between smoking cessation and surgery was associated with lower odds of major complication or mortality (adjusted odds ratio [aOR] for every additional week, 0.919; 95% confidence interval [CI], 0.850-0.993; P = 0.03). Compared to nonsmokers, patients who quit at least 3 weeks before surgery had similar odds of death or major complication (aOR, 1.005; 95% CI, 0.702-1.437; P = 0.98) whereas those who quit within 3 weeks of surgery had significantly higher odds of death or major complication (aOR, 1.698; 95% CI, 1.203-2.396; P = 0.003).

CONCLUSION

Smoking cessation at least 3 weeks prior to the surgical treatment of lung cancer is associated with reduced morbidity and mortality. Providers should aggressively encourage smoking cessation in the preoperative period, since it can disproportionately impact outcomes in early-stage lung cancer.

Association between imaging surveillance frequency and outcomes following surgical treatment of early-stage lung cancer

BACKGROUND

Recent studies have suggested that more frequent postoperative surveillance imaging via computed tomography following lung cancer resection may not improve outcomes. We sought to validate these findings using a uniquely compiled dataset from the Veterans Health Administration, the largest integrated health-care system in the United States.

METHODS

We performed a retrospective cohort study of veterans with pathologic stage I non-small cell lung cancer receiving surgery (2006-2016). We assessed the relationship between surveillance frequency (chest computed tomography scans within 2 years after surgery) and recurrence-free survival and overall survival.

RESULTS

Among 6171 patients, 3047 (49.4%) and 3124 (50.6%) underwent low-frequency (<2 scans per year; every 6-12 months) and high-frequency (≥2 scans per year; every 3-6 months) surveillance, respectively. Factors associated with high-frequency surveillance included being a former smoker (vs current; adjusted odds ratio [aOR] = 1.18, 95% confidence interval [CI] = 1.05 to 1.33), receiving a wedge resection (vs lobectomy; aOR = 1.21, 95% CI = 1.05 to 1.39), and having follow-up with an oncologist (aOR = 1.58, 95% CI = 1.42 to 1.77), whereas African American race was associated with low-frequency surveillance (vs White race; aOR = 0.64, 95% CI = 0.54 to 0.75). With a median (interquartile range) follow-up of 7.3 (3.4-12.5) years, recurrence was detected in 1360 (22.0%) patients. High-frequency surveillance was not associated with longer recurrence-free survival (adjusted hazard ratio = 0.93, 95% CI = 0.83 to 1.04, P = .22) or overall survival (adjusted hazard ratio = 1.04, 95% CI = 0.96 to 1.12, P = .35).

CONCLUSIONS

We found that high-frequency surveillance does not improve outcomes in surgically treated stage I non-small cell lung cancer. Future lung cancer treatment guidelines should consider less frequent surveillance imaging in patients with stage I disease.

Association Between Surgical Quality Metric Adherence and Overall Survival Among US Veterans With Early-Stage Non-Small Cell Lung Cancer

Importance

Surgical resection remains the preferred treatment for functionally fit patients diagnosed with early-stage non-small cell lung cancer (NSCLC). Process-based intraoperative quality metrics (QMs) are important for optimizing long-term outcomes following curative-intent resection.

Objective

To develop a practical surgical quality score for patients diagnosed with clinical stage I NSCLC who received definitive surgical treatment.

Design, Setting, and Participants

This retrospective cohort study used a uniquely compiled data set of US veterans diagnosed with clinical stage I NSCLC who received definitive surgical treatment from October 2006 through September 2016. The data were analyzed from April 1 to September 1, 2022. Based on contemporary treatment guidelines, 5 surgical QMs were defined: timely surgery, minimally invasive approach, anatomic resection, adequate lymph node sampling, and negative surgical margin. The study developed a surgical quality score reflecting the association between these QMs and overall survival (OS), which was further validated in a cohort of patients using data from the National Cancer Database (NCDB). The study also examined the association between the surgical quality score and recurrence-free survival (RFS).

Exposures

Surgical treatment of early-stage NSCLC.

Main Outcomes and Measures

Overall survival and RFS.

Results

The study included 9628 veterans who underwent surgical treatment between 2006 and 2016. The cohort consisted of 1446 patients who had a mean (SD) age of 67.6 (7.9) years and included 9278 males (96.4%) and 350 females (3.6%). Among the cohort, 5627 individuals (58.4%) identified as being smokers at the time of surgical treatment. The QMs were met as follows: timely surgery (6633 [68.9%]), minimally invasive approach (3986 [41.4%]), lobectomy (6843 [71.1%]) or segmentectomy (532 [5.5%]), adequate lymph node sampling (3278 [34.0%]), and negative surgical margin (9312 [96.7%]). The median (IQR) follow-up time was 6.2 (2.5-11.4) years. An integer-based score (termed the Veterans Affairs Lung Cancer Operative quality [VALCAN-O] score) from 0 (no QMs met) to 13 (all QMs met) was constructed, with higher scores reflecting progressively better risk-adjusted OS. The median (IQR) OS differed substantially between the score categories (score of 0-5 points, 2.6 [1.0-5.7] years of OS; 6-8 points, 4.3 [1.7-8.6] years; 9-11 points, 6.3 [2.6-11.4] years; and 12-13 points, 7.0 [3.0-12.5] years; P < .001). In addition, risk-adjusted RFS improved in a stepwise manner between the score categories (6-8 vs 0-5 points, multivariable-adjusted hazard ratio [aHR], 0.62; 95% CI, 0.48-0.79; P < .001; 12-13 vs 0-5 points, aHR, 0.39; 95% CI, 0.31-0.49; P < .001). In the validation cohort, which included 107 674 nonveteran patients, the score remained associated with OS.

Conclusions and Relevance

The findings of this study suggest that adherence to intraoperative QMs may be associated with improved OS and RFS. Efforts to improve adherence to surgical QMs may improve patient outcomes following curative-intent resection of early-stage lung cancer.

Comparison Between Veteran and Non-Veteran Populations With Clinical Stage I Non-small Cell Lung Cancer Undergoing Surgery

OBJECTIVE

The aim of this study was to compare quality of care and outcomes between Veteran and non-Veteran patients undergoing surgery for clinical stage I non-small cell lung cancer (NSCLC).

BACKGROUND

Prior studies and the lay media have questioned the quality of care that Veterans with lung cancer receive through the VHA. We hypothesized Veterans undergoing surgery for early-stage NSCLC receive high quality care and have similar outcomes compared to the general population.

METHODS

We performed a retrospective cohort study of patients with clinical stage I NSCLC undergoing resection from 2006 to 2016 using a VHA dataset. Propensity score matching for baseline patient- and tumor-related variables was used to compare operative characteristics and outcomes between the VHA and the National Cancer Database (NCDB).

RESULTS

The unmatched cohorts included 9981 VHA and 176,304 NCDB patients. The VHA had more male, non-White patients with lower education levels, higher incomes, and higher Charlson/Deyo scores. VHA patients had inferior unadjusted 30-day mortality (VHA 2.1% vs NCDB 1.7%, P = 0.011) and median overall survival (69.0 vs 88.7 months, P < 0.001). In the propensity matched cohort of 6792 pairs, VHA patients were more likely to have minimally invasive operations (60.0% vs 39.6%, P < 0.001) and only slightly less likely to receive lobectomies (70.1% vs 70.7%, P = 0.023). VHA patients had longer lengths of stay (8.1 vs 7.1 days, P < 0.001) but similar readmission rates (7.7% vs 7.0%, P = 0.132). VHA patients had significantly better 30-day mortality (1.9% vs 2.8%, P < 0.001) and median overall survival (71.4 vs 65.2 months, P < 0.001).

CONCLUSIONS

Despite having more comorbidities, Veterans receive exceptional care through the VHA with favorable outcomes, including significantly longer overall survival, compared to the general population.

Treatment and survival of de novo metastatic prostate cancer in US veterans

87

Background: Combination therapies using the androgen deprivation therapy (ADT) backbone have revolutionized treatment of metastatic hormone sensitive prostate cancer (mHSPC). Combinations include ADT plus docetaxel (DOC) or the androgen receptor targeting agents (ARTAs) abiraterone (AA), enzalutamide (ENZ), apalutamide (APA), and darolutamide (DAR). This study evaluates the utilization of these therapies in de novo mHSPC in a cohort of veterans and assesses recent overall survival (OS) of these therapies. Methods: Veterans were identified from 2012-2021 in the Veterans Affairs Prostate Cancer Data Core (VAPC) and oncology tumor registries using the initial pathological diagnosis of prostate cancer with SEER stage ‘distant’. All veterans had ADT initiated within 1 month prior and 3 months after diagnosis in VAPC. Additional therapies including DOC or ARTAs were collected from VAPC if initiated from 1 month prior to 4 months after ADT initiation. Data cut point was June 2022. Results: 5,006 patients with de novo mHSPC were identified with median age of 73.1 years (yrs), and 1338 (26.7%) identified as Black race. From 2012 to 2021, ADT alone was used in 3,569 (71.3%) of veterans, DOC in 438 (8.7%) and ARTAs in 999 (20.0%), wherein use of different ARTAs was AA in 783 (78.4%), ENZ in 204 (20.4%), APA in 10 (1.0%), and DAR in 2 (0.2%). Use of combination therapy for mHSPC increased from 3.1% in 2012-2013 to 61.2% in 2020-2021. Use of DOC peaked in 2016 and was used in 16.3% of veterans that year. Veterans treated with DOC were significantly younger (median 67.3 yrs, p<0.001) compared to veterans treated with ARTAs (73.1 yrs) or ADT alone (74.3 yrs). Veterans treated with combination therapies had longer median OS compared to ADT alone (37.2 vs. 29.3 months, p<0.001), with no significant difference between DOC and ARTA combinations (p=0.84). For 2,042 veterans with de novo mHSPC treated from 2018-2021, median OS of veterans treated with ADT+DOC (n=161, 35.3 months) and ADT+ARTA (n=849, 41.2 months) was longer than ADT alone (n=1,032, 29.3 months, p<0.001). There was no significant difference in median OS between DOC and ARTA combinations in this group (p=0.69). Conclusions: In veterans presenting with de novo mHSPC, use of initial combination therapy has increased, with the majority of veterans treated with ADT and an ARTA in 2020-2021. In this cohort, combination therapy was associated with longer OS compared to ADT alone and no significant differences were found between type of combination and OS. [Table: see text]

Survival in Black and non-Black patients with metastatic prostate cancer

101

Background: In the general population, Black men have greater incidence, lower five-year survival, and higher mortality due to prostate cancer when compared to white men. However, in clinical trials and studies of metastatic castrate resistant prostate cancer (mCRPC) in the Veterans Health Affairs (VHA) that excluded chemotherapy, Black men have longer overall survival (OS). We sought to analyze outcomes of Black men treated with androgen receptor targeting agents (ARTAs) abiraterone (AA) and enzalutamide (ENZ) in the VHA. Methods: Patients initially treated with AA or ENZ for mCRPC from May 2011 to June 2017 were identified within the VHA. Racial cohorts of Black and non-Black were determined from patient charts. ANOVA, Kaplan-Meier, and Cox proportional hazards modeling were used to assess the association between overall survival and covariates, including treatment, age, Charlson Comorbidity Index, body-mass index, PSA, year of treatment, prior docetaxel therapy, hemoglobin, creatinine clearance, bilirubin, and albumin at start of treatment. Results: Of 11,027 patients treated for mCRPC with ARTAs, 2550 (23.1%) were identified as Black. Black patients were significantly younger (72.6 vs. 75.8 years, p<0.001), had higher median PSA (60.3 vs. 37.0, p<0.001) and higher Charlson comorbidity index (4.5 vs. 3.9, p<0.001) with lower mean BMI (27.7 vs. 28.4, p<0.001) and higher rates of cardiovascular disease (62.0% vs. 59.8%, p=0.044) and diabetes (45.8% vs. 34.1%, p<0.001). Docetaxel was given more frequently to Black veterans both prior to ARTA (24.7% vs. 16.9%, p<0.001) and at any time (43.1% vs. 31.3%, p<0.001). Black men had a median 2.0 months longer OS than non-Black men (22.0 vs. 20.0, p<0.001) and decreased mortality in unadjusted models (HR 0.89, 95% CI 0.85-0.94) and multivariable models (aHR 0.76, 95% CI 0.72-0.80). Black veterans had longer OS with ENZ compared to AA (24.5 vs. 21.3 months, p<0.001) and decreased mortality (HR 0.83, 95% CI 0.75-0.92) in unadjusted models. However, there was no difference in OS between ENZ and AA in neither multivariable models in all Black men (aHR 0.95, 95% CI 0.85-1.05) nor Black men with cardiovascular disease or diabetes (n=1912, aHR 0.91, 95% CI 0.80-1.03). Conclusions: In the VHA, which provides more equitable access to care, Black men have longer OS with ARTAs compared to non-Black men and increased use of chemotherapy. Importantly, Black men are significantly younger (>3 years) when treated for mCRPC, with higher PSA, and higher rates of comorbid diseases.

Frailty and overall survival in metastatic castration-resistant prostate cancer treated with abiraterone or enzalutamide

71

Background: Abiraterone (ABI) and Enzalutamide (ENZ) are both treatment options for metastatic castration-resistant prostate cancer (mCRPC). However, both drugs have differing pharmacodynamics, so patient factors may selectively impact drug efficacy. Age-associated health deficits make older adults variably susceptible to disease under a syndrome termed frailty. The average age of initial prostate cancer diagnosis is age 66, and the average time to mCRPC progression is 11.7 years. Thus, frailty is an important patient factor to consider in mCRPC, and it may play a role in personalizing drug selection. Methods: Patients treated with ABI or ENZ for mCRPC from September 2014 to June 2017 were identified in the VA and followed until April 2020. Frailty was assessed using the VA frailty index, which looks at ICD-10, CPT, and HCPCS codes to assign a standardized frailty score between 0-1. Patients were categorized as frail if their VA-FI scores were > 0.2. The primary outcome was overall survival (OS) between the ABI and ENZ treatment groups. Cox regression models included age, race, body mass index, PSA, and total Charlson Comorbidity Index (CCI). For frail patients, a propensity score-matched cohort was also created by matching age, race, CCI, and total VA-FI between ABI and ENZ treatment groups. Results: Of the 5,822 patients identified, 57% were initially treated with ABI and 43% with ENZ. The ABI group had a lower mean VA-FI score of 0.192 compared to the ENZ group of 0.203 (p=0.004). Frail patients were older: mean 74.9 years vs. 76.1 years for non-frail (p<0.001). Frail patients had shorter survival than non-frail (18.5 vs. 26.6 months, p<0.001). In multivariable models, frailty was associated with increased risk of death (aHR 1.32, 95% CI 1.23-1.42). Among non-frail patients (n=3508, 60.3%), there was no significant difference in OS between ABI and ENZ treatment. Among frail patients (n=2314, 39.7%), patients treated with ENZ had a 3.5 month greater median OS than ABI (20.7 vs. 17.2 months, p = 0.0003 by log-rank). In frail patients, ENZ was associated with reduced risk of death (aHR 0.85, 95% CI 0.78-0.94). In a propensity matched cohort of 2070 patients, the enzalutamide treatment group had a 3.2 months greater median OS in the enzalutamide group than the abiraterone group (24.1 months vs. 20.9 months, p < 0.001). Conclusions: ENZ was associated with improved OS compared to ABI among frail veterans, but not among non-frail veterans. The improved survival remained significant in a propensity score-matched cohort and models including important covariates. Further assessment of the value of frailty in personalizing drug treatment is warranted to improve the care of older adults with advanced prostate cancer.

Survival and hemoglobin A1c in metastatic castrate resistant prostate cancer

75

Background: The two common therapies for metastatic castrate resistant prostate cancer (mCRPC), enzalutamide (ENZ) and abiraterone (AA), have different effectiveness in patients with diabetes mellitus and obesity due to different mechanisms of action, along with AA requiring the co-administration of prednisone. However, no prior study has assessed responses to treatment based on glycated hemoglobin (HbA1c) while accounting for body-mass index (BMI). Methods: Patients treated with AA or ENZ from September 10, 2014 to June 2, 2017 were identified within the Veterans Health Administration. The patients were classified by most recent HbA1c values (<5.6%, 5.6%-6.4%, 6.5%-7.1%, ≥7.2%) collected prior to the start of AA or ENZ. Kaplan Meier and Cox proportional hazards modeling was performed to assess the association between overall survival and covariates including age, Charlson Comorbidity Index, BMI, baseline PSA, and HbA1c. Results: 3421 veterans treated with AA or ENZ had HbA1c data available. 658 patients with HbA1c <5.6%, 1430 with 5.6-6.4%, 667 with 6.5%-7.1%, and 666 with HbA1c ≥7.2. Kaplan Meier analysis showed the following median survival in months with ENZ vs AA: <5.6% = 22.1 vs 24.5 (p = 0.04 by log-rank), 5.6%-6.4% = 27.7 vs 22.6 (p = 0.01), 6.5%-7.1% = 23.0 vs 19.8 (p = 0.005), ≥7.2% = 26.0 vs 21.0 (p = 0.04). Cox models showed no difference in median survival between ENZ vs AA in patients with HbA1c <5.6%, adjusted hazard ratio (aHR) 1.15 (95% CI, 0.960-1.370). However, there was significantly longer survival in patients who received ENZ compared to AA in all other groups as follows: 5.6%-6.4% aHR 0.86 (95% CI, 0.759-0.965), 6.5%-7.1% aHR 0.74 (0.623-0.879) and ≥7.2% aHR 0.80 (0.669-0.948). Additionally, in patients treated with AA, higher HbA1c values were associated with inferior survival compared to HbA1c <5.6%, aHR 1.40 (1.19-1.65) for 6.5-7.1% and aHR 1.25 (1.05-1.48) for ≥7.2%. Conclusions: In patients with HbA1c ≥5.6%, ENZ was associated with longer overall survival compared to AA, even when including baseline BMI. Additionally, in patients treated with AA, higher HbA1c values had inferior survivals compared to patients with HbA1c <5.6%. No difference in survival was observed across the HbA1c strata with ENZ. Further studies of interactions between patient factors and treatments are warranted to guide treatment selection for prostate cancer therapy.

Survival trends in de novo metastatic prostate cancer: SEER and Veterans Affairs comparison

28

Background: Advances in treatment for metastatic prostate cancer (mPC) have improved overall survival (OS) in clinical trials for mPC over the last 20 years. It is unclear whether these changes from trials have translated to improvements in survival in the real world. We sought to characterize trends in OS among patients with newly diagnosed mPC in two large national registries. Methods: Patients diagnosed from 2000-2019 were included. Patients from SEER-17 were included if stage at diagnosis was distant. For years prior to 2004, SEER Historic Stage A was used. Patients in the Veterans Affairs Prostate Cancer data core (VA) were included if the SEER summary stage variable was distant in the first record of prostate cancer in VA or oncology registry data for veterans diagnosed after 2018. Results: 55,661 patients were identified in SEER and 14,904 patients were identified in VA. Median age at presentation was 72 years in both datasets, with 16.6% identified as Black in SEER and 28.5% Black in VA. Median OS from 2000-2004 to 2015-2019 in SEER increased from 25 to 31 months, corresponding to a hazard ratio (HR) of 0.82 (p <0.001); median OS in VA increased from 25.8 to 30.9 months, corresponding to a HR of 0.912 (p=0.003). Patients <70 years of age had median OS that increased from 31 to 41 months (HR 0.78, p <0.001) in SEER and 34.4 to 42.2 months (HR 0.87, p=0.003) in VA compared to patients 70+ in SEER (21 to 26 months, HR=0.84, p<0.001) and in VA (21.6 to 25.6 months, HR=0.935, p=0.03). In SEER, black patients had worse survival compared to white patients (HR 1.10, p<0.001). Survival improvement over time in SEER was seen for both black (HR 0.81, p<0.001) and white (HR 0.83, p<0.001) patients. In VA, black patients had better OS compared to white patients (HR 0.96, p=0.0475). Survival improvement over time in VA was seen in black (HR 0.84, p<0.001), but was not significant in white (HR 0.94, p=0.052) patients. Conclusions: This real-world analysis demonstrates that median OS in de novo mPC has improved over the last 20 years, particularly in patients <70 years of age. However, these improvements are less than what has been observed in clinical trials. Black patients had inferior OS in SEER compared to white patients but in the VA black patients had better OS and an improvement in OS over time, potentially reflecting more equal access to care in the VA system. [Table: see text]

Comparative effectiveness of abiraterone and enzalutamide in the first-line treatment of metastatic castration-resistant prostate cancer (mCRPC): A retrospective cohort study in a large database of deeply curated EHR real-world data (RWD) from community oncology practices in the US

175

Background: Abiraterone(A) and enzalutamide(E), both oral androgen receptor targeted agents, are available as first-line treatment options for mCRPC patients. Direct comparisons of efficacy have not been performed for mCRPC patients primarily receiving their cancer care outside of academic centers or integrated health care systems. The study aims to evaluate the real-world effectiveness between first-line A and E-containing regimens in mCRPC patients primarily receiving care in the US community oncology setting. Methods: Patients were selected from ConcertAI Patient 360 Prostate data product, a large de-identified database of deeply curated EHR RWD, sourced from data sharing agreements with community oncology practices. mCRPC patients treated with a first-line A or E-cont. regimen between 1/2011 and 6/2022 were included. OS, TTNT, TTD outcomes were described using KM estimates and evaluated with Cox proportional hazard (HR) model. Confounding was addressed with inverse probability treatment weighting (IPTW) propensity scores based on age, BMI, ECOG, prior anti-androgen exposure, smoking status, comorbidities, and nadir PSA. Sensitivity analysis evaluated KM and HR for each covariate strata. Hazard ratios were also evaluated with multiple imputation by chained equations for missing covariates. Results: From 3,578 mCRPC patients, 1,210 (33.8%) received E-cont. regimen and 1,357 (37.9%) received A-cont. regimen(ref) with a median of 8 months duration for both drugs. Adjusted HR (aHR) for all three outcomes showed a slight increase in effectiveness for E albeit not significant (OS (aHR 0.99, CI 0.87-1.12), TTNT (aHR 0.98, CI 0.89-1.08). Adjusted model including imputation (iHR) supported unimputed results (OS (iHR 0.97, CI 0.88-1.07), TTNT (aHR 0.94, CI 0.9-1.10). The HRs for OS, TTNT and TTD in sicker patients were consistent (2+ ECOG TTNT (aHR 0.95, 0.81-1.12)), (BMI >30, TTNT (aHR 0.84, 0.61-1.18)), and reached significance for some models (2+ ECOG TTD (aHR 0.66, 0.48-0.91)). Conclusions: First-line E-cont. regimens consistently showed increased effectiveness in outcomes compared to A-cont. regimens in mCRPC patients treated in community oncology setting. The effects sizes are modest and did not reach significance, however analysis of the sickest patients showed a trend of consistently larger effect sizes which reached significance for some outcomes. More work needs to be done to evaluate if these results support findings from other RWD sources.

Assessment of Updated Commission on Cancer Guidelines for Intraoperative Lymph Node Sampling in Early Stage NSCLC

INTRODUCTION

The American College of Surgeons Commission on Cancer recently updated its sampling recommendations for early stage NSCLC from at least 10 lymph nodes to at least one N1 (hilar) and three N2 (mediastinal) lymph node stations. Nevertheless, intraoperative lymph node sampling minimums remain subject to debate. We sought to evaluate these guidelines in patients with early stage NSCLC.

METHODS

We performed a cohort study using a uniquely compiled data set from the Veterans Health Administration. We manually abstracted data from operative notes and pathology reports of patients with clinical stage I NSCLC receiving surgery (2006-2016). Adequacy of lymph node sampling was defined using count-based (≥10 lymph nodes) and station-based (≥three N2 and one N1 nodal stations) minimums. Our primary outcome was recurrence-free survival. Secondary outcomes were overall survival and pathologic upstaging.

RESULTS

The study included 9749 patients. Count-based and station-based sampling guidelines were achieved in 3302 (33.9%) and 2559 patients (26.3%), respectively, with adherence to either sampling guideline increasing over time from 35.6% (2006) to 49.1% (2016). Adherence to station-based sampling was associated with improved recurrence-free survival (multivariable-adjusted hazard ratio = 0.815, 95% confidence interval: 0.667-0.994, p = 0.04), whereas adherence to count-based sampling was not (adjusted hazard ratio = 0.904, 95% confidence interval: 0.757-1.078, p = 0.26). Adherence to either station-based or count-based guidelines was associated with improved overall survival and higher likelihood of pathologic upstaging.

CONCLUSIONS

Our study supports station-based sampling minimums (≥three N2 and one N1 nodal stations) for early stage NSCLC; however, the marginal benefit compared with count-based guidelines is minimal. Further efforts to promote widespread adherence to intraoperative lymph node sampling minimums are critical for improving patient outcomes after curative-intent lung cancer resection.

Racial Disparities in the Surgical Treatment of Clinical Stage I Non-Small Cell Lung Cancer Among Veterans

BACKGROUND

Prior studies in the civilian population have reported racial disparities in lung cancer outcomes following surgical treatment, including inferior quality of care and worse survival. It is unclear if racial disparities exist in the Veterans Health Administration (VHA), the largest integrated health care system in the United States.

RESEARCH QUESTION

Do racial disparities affect early-stage non-small cell lung cancer (NSCLC) outcomes following surgical treatment within the VHA?

STUDY DESIGN AND METHODS

This retrospective cohort study was conducted in veterans with clinical stage I NSCLC undergoing surgical treatment in the VHA system. Demographic characteristics, access to care, surgical quality measures, and short- and long-term oncologic outcomes between White and Black veterans were evaluated.

RESULTS

From 2006 to 2016, a total of 18,800 veterans with clinical stage I NSCLC were included. The rates of definitive surgical treatment were similar between Black (57.3%) and White (58.1%) veterans (P = .42). The final study cohort included 9,842 patients receiving surgical treatment, of whom 8,356 (84.9%) were White and 1,486 (15.1%) were Black. Black patients were younger and more likely to smoke, although comorbidities were similar between the two groups. Black patients were somewhat less likely to receive adequate lymph node sampling (30.6% vs 33.3%; P = .050); however, other access-to-care metrics and surgical quality measures, including rates of anatomic lobectomy (71.9% vs 69.4%; P = .189) and positive margins (3.2% vs 3.1%; P = .955), were similar between the two groups. Although Black veterans were less likely to experience major postoperative complications, there was no difference in 30-day readmission, 30-day mortality, or disease-free survival between the two groups. Black patients had significantly better risk-adjusted overall survival (hazard ratio, 0.802; 95% CI, 0.729-0.883; P < .001).

INTERPRETATION

Among veterans with NSCLC undergoing surgical treatment through the VHA, Black patients received comparable care with equivalent if not superior outcomes compared with White patients.

Medicare Spending on Drugs With Accelerated Approval

BACKGROUND

The U.S. Food and Drug Administration provides accelerated approval to drugs on the basis of surrogate end points deemed to be "reasonably likely" to predict clinical benefit. To receive full approval, drugs must complete a confirmatory trial. Although most accelerated approved drugs ultimately receive full approval, others remain on the market without full approval for many years, and some are withdrawn before full approval is granted. Until confirmatory trials are completed and full approval is granted, there is uncertainty surrounding each drug's clinical benefits.

OBJECTIVE

To estimate fee-for-service Medicare payments on accelerated approved drugs without full approvals.

DESIGN

Cross-sectional analysis.

SETTING

Fee-for-service Medicare Part B and Part D drug claims in 2019.

PARTICIPANTS

Beneficiaries enrolled in Medicare Part B and Part D plans.

MEASUREMENTS

Medicare spending for drugs treating accelerated approved indications without full approval, beneficiary spending, and drug characteristics.

RESULTS

In 2019, 45 drugs associated with 69 accelerated approved indications lacked full approval. Of those, the fee-for-service Medicare program spent $1.2 billion on 36 drugs across 55 indications. Medicare beneficiaries had $209 million in out-of-pocket spending on these drugs. Oncology drugs represented 82% of these indications and 72% of the Medicare spending. Extrapolating to Medicare Advantage, total Medicare spending on these drugs in 2019 was $1.8 billion.

LIMITATIONS

The study drugs may have clinical benefit and may come to receive full approval after this analysis. The algorithm used to identify accelerated approved indications is novel. Generalizability to other years is unclear.

CONCLUSION

In 2019, fee-for-service Medicare spent $1.2 billion on accelerated approved drugs without full approval. Medicare should adjust incentives to encourage sponsors to complete confirmatory trials as soon as possible.

PRIMARY FUNDING SOURCE

Laura and John Arnold Foundation.

Different risks of hemorrhage in patients with elevated international normalized ratio from chronic liver disease versus warfarin therapy, a population-based retrospective cohort study

BACKGROUND

Patients with chronic liver disease (CLD) often present with an elevated international normalized ratio (INR). Although elevated INR reflects a higher risk of hemorrhage among warfarin users, its clinical significance in CLD patients is less clear.

OBJECTIVES

We used Veterans Health Administration data to quantify the association between INR and (non-variceal) hemorrhage in patients with CLD compared to warfarin users.

METHODS

We performed a multivariate competing risk analysis to study the association between INR and hemorrhage in the two cohorts. We used an interaction term between INR and cohort (CLD/warfarin users) to test if INR had different effects on hemorrhage in the two cohorts.

RESULTS

Data from 80 134 patients (14, 412 with CLD and 65, 722 taking warfarin) were analyzed. The effect of INR on the risk of hemorrhage differed between CLD patients and warfarin users (interaction P < .001). As INR increased above 1.5, the adjusted hazard ratio (aHR) for hemorrhage in CLD patients increased to 2.25 but remained fairly constant with further elevation of INR values. In contrast, the risk of hemorrhage in patients taking warfarin remained low with INR in the subtherapeutic (INR <2.0) and therapeutic ranges (INR 2.0-3.0), and increased exponentially with INR in the supratherapeutic range (aHR 1.64 with INR >3.0-3.5, and 4.70 with INR >3.5).

CONCLUSIONS

The relationship between INR and risk of hemorrhage in CLD patients is different from that in warfarin users. Caution should be exercised extrapolating data from warfarin users to make clinical decisions in CLD patients.

Intraoperative quality metrics and association with survival following lung cancer resection

8502

Background: Surgical resection remains the preferred treatment for functionally fit patients with clinical stage I non-small cell lung cancer (NSCLC). Process-based intra-operative quality metrics (QMs) are important for optimizing long-term outcomes following curative-intent resection. We sought to characterize overall survival using a novel surgical quality score. Methods: We performed a retrospective cohort study using a uniquely compiled dataset of US Veterans with clinical stage I NSCLC receiving definitive surgical treatment. Based on contemporary treatment guidelines, we defined five surgical QMs: timely surgery (within 12 weeks of diagnosis), minimally invasive approach, anatomic resection via lobectomy, adequate nodal sampling (≥10 nodes), and negative margin. Using a multivariable Cox proportional hazards model, we developed a surgical quality score reflecting the relationship between these QMs and overall survival (OS). We also examined the relationship between this score and disease-free survival (DFS). Results: The study included 9,628 Veterans undergoing surgical treatment between 2006 and 2016. QMs were met as follows: timely surgery (n=6,633, 68.9%), minimally invasive approach (n=3,986, 41.4%), lobectomy (n=6,843, 71.1%), adequate nodal sampling (n=3,278, 34.1%), and negative surgical margin (n=9,312, 96.7%). The median (IQR) follow-up was 6.2 (2.5-11.4) years. A normalized score from 0 (no QMs met) to 100 (all QMs met) was constructed, with higher scores reflecting progressively improved risk-adjusted OS (Table). The median (IQR) OS was 86.8 (37.8-149.6) months in the highest score quintile versus 25.3 (7.1-45.8) months in the lowest score quintile. Recurrence was detected in 2,268 (23.6%) patients. Higher surgical quality score was associated with improved DFS (multivariable-adjusted hazard ratio, aHR 0.494, 95% CI 0.245-0.997). Conclusions: Adherence to intra-operative QMs is associated with markedly improved overall and disease-free survival. Efforts to improve adherence to surgical QMs can dramatically improve patient outcomes following curative-intent resection of early-stage lung cancer. [Table: see text]

The Impact of Persistent Smoking After Surgery on Long-term Outcomes After Stage I Non-small Cell Lung Cancer Resection

BACKGROUND

Smoking at the time of surgical treatment for lung cancer increases the risk for perioperative morbidity and mortality. The prevalence of persistent smoking in the postoperative period and its association with long-term oncologic outcomes are poorly described.

RESEARCH QUESTION

What is the relationship between persistent smoking and long-term outcomes in early-stage lung cancer after surgical treatment?

STUDY DESIGN AND METHODS

We performed a retrospective cohort study using a uniquely compiled Veterans Health Administration dataset of patients with clinical stage I non-small cell lung cancer (NSCLC) undergoing surgical treatment between 2006 and 2016. We defined persistent smoking as individuals who continued smoking 1 year after surgery and characterized the relationship between persistent smoking and disease-free survival and overall survival.

RESULTS

This study included 7,489 patients undergoing surgical treatment for clinical stage I NSCLC. Of 4,562 patients (60.9%) who were smoking at the time of surgery, 2,648 patients (58.0%) continued to smoke at 1 year after surgery. Among 2,927 patients (39.1%) who were not smoking at the time of surgical treatment, 573 (19.6%) relapsed and were smoking at 1 year after surgery. Persistent smoking at 1 year after surgery was associated with significantly shorter overall survival (adjusted hazard ration [aHR], 1.291; 95% CI, 1.197-1.392; P < .001). However, persistent smoking was not associated with inferior disease-free survival (aHR, 0.989; 95% CI, 0.884-1.106; P = .84).

INTERPRETATION

Persistent smoking after surgery for stage I NSCLC is common and is associated with inferior overall survival. Providers should continue to assess smoking habits in the postoperative period given its disproportionate impact on long-term outcomes after potentially curative treatment for early-stage lung cancer.

Natural language processing of Veterans’ electronic health records to confirm diagnoses of monoclonal gammopathy of undetermined significance

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Background: The Veterans Health Administration (VHA) provides extensive electronic health records (EHRs) on Veterans nationwide. Our prior studies utilized VHA data to study the risk of progression from monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma. These studies relied on International Classification of Disease (ICD) codes and manual abstraction on clinical notes to both identify and verify MGUS patients. Diagnosis confirmation is necessary because many providers place a diagnosis on the clinical notes to order lab tests, which is often left in the EHR despite a negative test result. However, manual abstraction is labor intensive and time consuming. With the advancement in natural language processing (NLP), we developed a model to make MGUS confirmation more efficient. Methods: We randomly selected 700 patients within patients diagnosed with MGUS from 1999-2021 in the VHA identified via ICD codes. A random sample of 500 patients were selected and split into the training (80%) and the testing (20%) sets. The remainder (n = 200) served as the validation set. There were 32,708 unstructured hematology/oncology Text Integration Utility reports and 9,237 lab reports (including 2,322 discrete results and 6,915 unstructured comments). All reports were manually reviewed to confirm MGUS diagnoses and served as the reference standard. We compiled three lists of keywords suggestive of MGUS diagnosis, subtypes of immunoglobulins, and negation modifiers. We trained a symbolic NLP model to identify diagnoses using combinations of the lists along with M-protein levels from lab reports. The optimized combination that gave the highest recall and precision from the training set was used and evaluated on the testing and validation sets. Results: Among patients with ICD codes for MGUS, manual abstraction confirmed 84% MGUS diagnoses in the testing set and 80% in the validation set. Our NLP model in the training set confirmed 75% and achieved recall, precision, accuracy, and F1 score of 88.1, 98.7, 89.0, and 93.1%, respectively; in the validation set, our rule confirmed 76% patients and the recall, precision, accuracy, and F1 score were 89.4, 94.7, 87.5, and 92.0%, respectively. On average data abstraction took five minutes per patient (excluding data loading time), whereas NLP model completed 13 patients per minute. Conclusions: The developed NLP model to confirm MGUS diagnosis improves accuracy in diagnosis, compared to ICD codes alone. While the performance is similar to that of manual abstraction, our NLP model is an efficient and viable method in MGUS diagnosis confirmation. [Table: see text]

Effect of Androgen Suppression on Clinical Outcomes in Hospitalized Men With COVID-19: The HITCH Randomized Clinical Trial

IMPORTANCE

SARS-CoV-2 entry requires the TMPRSS2 cell surface protease. Antiandrogen therapies reduce expression of TMPRSS2.

OBJECTIVE

To determine if temporary androgen suppression induced by degarelix improves clinical outcomes of inpatients hospitalized with COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

The Hormonal Intervention for the Treatment in Veterans With COVID-19 Requiring Hospitalization (HITCH) phase 2, placebo-controlled, double-blind, randomized clinical trial compared efficacy of degarelix plus standard care vs placebo plus standard care on clinical outcomes in men hospitalized with COVID-19 but not requiring invasive mechanical ventilation. Inpatients were enrolled at 14 Department of Veterans Affairs hospitals from July 22, 2020, to April 8, 2021. Data were analyzed from August 9 to October 15, 2021.

INTERVENTIONS

Patients stratified by age, history of hypertension, and disease severity were centrally randomized 2:1 to degarelix, (1-time subcutaneous dose of 240 mg) or a saline placebo. Standard care included but was not limited to supplemental oxygen, antibiotics, vasopressor support, peritoneal dialysis or hemodialysis, intravenous fluids, remdesivir, convalescent plasma, and dexamethasone.

MAIN OUTCOMES AND MEASURES

The composite primary end point was mortality, ongoing need for hospitalization, or requirement for mechanical ventilation at day 15 after randomization. Secondary end points were time to clinical improvement, inpatient mortality, length of hospitalization, duration of mechanical ventilation, time to achieve a temperature within reference range, maximum severity of COVID-19, and the composite end point at 30 days.

RESULTS

The trial was stopped for futility after the planned interim analysis, at which time there were 96 evaluable patients, including 62 patients randomized to the degarelix group and 34 patients in the placebo group, out of 198 initially planned. The median (range) age was 70.5 (48-85) years. Common comorbidities included chronic obstructive pulmonary disorder (15 patients [15.6%]), hypertension (75 patients [78.1%]), cardiovascular disease (27 patients [28.1%]), asthma (12 patients [12.5%]), diabetes (49 patients [51.0%]), and chronic respiratory failure requiring supplemental oxygen at baseline prior to COVID-19 (9 patients [9.4%]). For the primary end point, there was no significant difference between the degarelix and placebo groups (19 patients [30.6%] vs 9 patients [26.5%]; P = .67). Similarly, no differences were observed between degarelix and placebo groups in any secondary end points, including inpatient mortality (11 patients [17.7%] vs 6 patients [17.6%]) or all-cause mortality (11 patients [17.7%] vs 7 patents [20.6%]). There were no differences between degarelix and placebo groups in the overall rates of adverse events (13 patients [21.0%] vs 8 patients [23.5%) and serious adverse events (19 patients [30.6%] vs 13 patients [32.4%]), nor unexpected safety concerns.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial of androgen suppression vs placebo and usual care for men hospitalized with COVID-19, degarelix did not result in amelioration of COVID-19 severity.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04397718.

Treatment outcomes of patients with metastatic prostate cancer and co-morbid diabetes mellitus

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Background: In metastatic castrate resistant prostate cancer (mCRPC) there is a lack of studies that explore the interaction of comorbidities on treatment outcomes, which presents a challenge in choosing the right drug. In patients with diabetes mellitus, two common therapies, enzalutamide (ENZ) and abiraterone (ABI) have different effectiveness due to different mechanisms of action and because ABI requires co-administration of prednisone. Thus, in this study, we aim to assess the survival of patients with comorbid diabetes treated with ENZ and ABI. Methods: Patients treated with AA or ENZ for mCRPC from September 10, 2014, to June 2, 2017 were identified within the Veterans Health Administration. For these patients, presence of diabetes or complicated diabetes was determined using the Charlson method from the International Classification of Diseases (ICD) 9/10 codes. A Kaplan–Meier time to event analysis and the cox proportional hazards modeling was used to analyze the data with the latter including covariates such as age, Charlson Comorbidity Index, body-mass index, treatment with bone-directed therapy, black race, and baseline PSA at start of treatment with ENZ or ABI. Results: We identified 5822 patients treated for mCRPC, of which 2202 had diabetes and were treated using either ENZ (n = 1041) or ABI (n = 1161). Median survival of patients with diabetes treated with ENZ was 3 months longer than in patients treated with ABI (23.8 vs. 20.8, p = 0.002 by log-rank). In 3620 patients without diabetes, no significant difference in median survival (24.7 vs. 22.7 months, p = 0.065) was seen between ENZ (n = 1463) and ABI (n = 2157). In a multivariable model, ENZ was associated with improved survival in patients with diabetes (adjusted HR 0.87, 95% CI 0.79-0.97) and in patients without diabetes (adjusted HR 0.90, 95% CI 0.83-0.98). Conclusions: ENZ was associated with improved 3-month median survival in patients with diabetes compared to ABI in unadjusted analyses. Additionally, in adjusted analyses the cox proportional model also showed significantly better survival in mCRPC patients treated with ENZ both with and without diabetes, although the findings are more robust for patients with diabetes. The cause of these differences is unknown, so there may be differences in efficacy and adverse events between the two agents in real-world use. Further assessment of patient outcomes with comorbid disease is appropriate to improve care of patients with advanced prostate cancer.

Hospitalizations and common infections among veterans treated for metastatic prostate cancer

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Background: Abiraterone (AA) and Enzalutamide (ENZ) are both hormone therapies used in the treatment of metastatic castrate resistant prostate cancer (mCRPC). Due to a lack of large comparative studies, they are currently used interchangeably, but may have different adverse outcomes in patients with comorbid conditions. In this study, we aim to identify adverse events that lead to hospitalization in patients treated with ENZ versus AA. Methods: Patients treated with AA or ENZ between September 10, 2014 and June 3, 2017 were identified in the Veterans Health Administration and followed until April 2020. We obtained ICD 9/10 codes using the Veterans Health Administration Informatics and Computing Infrastructure (VINCI) platform among VA hospitalizations. We used the top 3 ICD 9/10 codes at discharge to ascertain causation of hospitalization. Infections were defined by ICD 9 and ICD 10 codes falling into 3 categories: pneumonia (ICD9: 480.x-486.x, ICD10: J13.x-J18.x), urinary tract infection (ICD9: 599.0, ICD10: N39.0), and sepsis (ICD9: 995.91, 995.92, ICD10: A40.x-A41.x, R65.20, R65.21). Results: 5,822 patients were identified for the cohort. The mean age of the patients was 75.3 years old, with a mean Charlson comorbidity index of 4.2. Patients first treated with enzalutamide were older (75.8 vs 75.0 years, p = 0.002) with a higher mean Charlson comorbidity score (4.4 vs 4.1, p < 0.001). There were no significant differences in time from initial diagnosis of PCa to treatment with AA or ENZ. Of the 5,822 patients, 2504 (43.0%) were initially treated with ENZ, and 3,318 (57.0%) with AA. Total hospitalization rate in events/person-years was 1.52 and 1.29 for the abiraterone and enzalutamide cohorts respectively, with an incidence rate difference (IDR) of 0.23 (p < 0.0001, CI: 0.14-0.32), indicating a statistically significant increase in hospitalizations among the abiraterone cohort. Of the total hospitalizations, 1/4th of them were caused by infections defined as pneumonia, sepsis, or UTI. The incidence in events/person-years for the combined infections in the AA and ENZ cohort was 0.99 and 0.86 (IDR = 0.13, p = 0.06) respectively, 0.97 and 0.86 (IDR = 0.11, p = 0.26) for UTI; 0.76 and 0.74 (IDR = 0.021, p = 0.82) for sepsis; and 0.82 and 0.71 (IDR = 0.12, p = 0.22) for pneumonia. This shows no statistical difference in infection rate between the two treatments. Conclusions: The increase in incidence rate of hospitalizations of 0.23 events/person-years among the abiraterone group, despite greater age and comorbidities in the enzalutamide group, suggests an increased risk of adverse events requiring hospitalization in patients started on abiraterone initially. However, no difference was seen in incidence of the three most common infections between cohorts. This suggests that the difference in mechanism of action and use of prednisone with AA may not be of clinical significance with regards to risk for infection.

Survival of patients with metastatic prostate cancer and comorbid obesity

116

Background: In metastatic castrate resistant prostate cancer (mCRPC), the oral treatments of enzalutamide (ENZ) and abiraterone (AA) are used interchangeably because there are few large-scale comparative studies of the therapies. However, both drugs have different mechanisms of action, AA being an androgen biosynthesis inhibitor and ENZ being an androgen receptor inhibitor, so there may be therapeutic variance between the two drugs based on their interactions with comorbid conditions like obesity. Obesity not only increases the risk of other comorbidities, like heart disease, diabetes, and stroke, but has also been implicated in the development of CRPC. Methods: Patients treated with abiraterone or enzalutamide from September 10, 2014 to June 2, 2017 in the Veterans Health Administration were identified via pharmacy records. Among this population, patients were separated into body mass index (BMI) categories for underweight ( < 18.5), normal (18.5 to < 25), overweight (25 to < 30), and obese ( > 30). Age, Charlson Comorbidity Index and mCRPC treatments were collected and analyzed for the primary outcome of survival via the Kaplan-Meier method. A multivariate Cox proportional hazard model was performed with the following variables: BMI, Charlson Comorbidity Index, age, Black race, treatment with bone-directed therapy, and baseline PSA. Results: In patients with BMI > 25, there was a significantly improved overall survival for treatment with ENZ (n = 1623) over AA (n = 2159), with medians of 30.0 and 27.0 months respectively (p = 0.002). There was no significant difference in survival for patients with BMI < 25 (p = 0.48), with median survival of 17.7 months for ENZ (n = 589) and 16.1 months for AA (n = 860). The overall survival difference between underweight (n = 113), normal (n = 1336), overweight (n = 1879), and obese (n = 1903) groups shows significant increase in survival with increasing BMI, with the median survival durations of 9.2, 15.9, 23.9, and 29.8 months respectively (p < 0.001). This finding was corroborated by the Cox proportional hazard model, with the data indicating an increased risk of death (aHR = 1.58; 95% CI: 1.29, 1.94; p < 0.001) with the underweight group and decreased risk with the overweight (aHR = 0.75; 95% CI: 0.69, 0.81; p < 0.001) and obese (aHR = 0.64; 95% CI: 0.59, 0.70; p < 0.001) groups. Conclusions: Treatment with ENZ was associated with longer survival for mCRPC patients with overweight and obesity (BMI > 25) over AA. Otherwise, for normal and underweight patients (BMI < 25), there was no significant difference in overall survival between the two drugs. Higher BMI is associated with improved survival, suggesting a protective effect of obesity in mCRPC patients. While the reason for this finding warrants further investigation, similar findings have been seen in obese patients in some hormone driven cancers, like breast cancer and myeloma.

Statin type and survival of patients with metastatic castrate-resistant prostate cancer receiving abiraterone and enzalutamide: A nationwide retrospective cohort study

50

Background: Studies have suggested that statin use is associated with prostate cancer mortality. However, uncertainties exist in how the solubility profile of statins impact cancer outcomes. Lipophilic statins have greater accessibility in extrahepatic tissues, which may lead to stronger inhibitory effects on cancer cells, whereas hydrophilic statins exhibit greater hepato-selectivity and therefore less likely to cause drug interactions and adverse events. Abiraterone (ABI) and enzalutamide (ENZ) are antiandrogen agents used in metastatic castrate-resistant prostate cancer (mCRPC). In this study, we sought to examine whether statin usage and lipophilicity of statins is associated with survival benefits in mCRPC patients receiving ABI or ENZ. Methods: We conducted a nationwide retrospective cohort study of the Veteran Affairs population. Patients with mCRPC who received statin therapy one year prior to initiation of either ABI or ENZ between 9/10/2014 and 6/3/2017 were included and followed until April 2020. Statins were categorized as lipophilic (atorvastatin, simvastatin, lovastatin, fluvastatin, cerivastatin, pitavastatin) and hydrophilic (rosuvastatin and pravastatin). A cox proportional hazards model was used to estimate adjusted hazards ratio (aHR) with 95% confidence interval (CI) of overall survival after controlling for known prognostic factors including age, Charlson-Romano Comorbidity Index, use of bone-modifying agents, Body-Mass Index, and prostate specific antigen levels. Results: A total of 4919 patients (mean age 75.0 years) were included in our cohort. Of those, 969 patients (19.7%) received lipophilic statins and 452 patients (9.2%) received hydrophilic statins. After adjusting for known factors, statin use was not associated with improved overall survival (aHR 0.93; 95% CI 0.87 – 1.00). Similarly, the use of lipophilic statins (aHR 0.98; 95% CI 0.90 – 1.06) or hydrophilic statins (aHR 0.90; 95% CI 0.80 – 1.01) were not associated with improved overall survival in mCRPC. Conclusions: Our study found no differences in overall survival between mCRPC patients with statin use compared to those without statins. When analyzing statin lipophilicity, we saw a higher trend towards survival in the hydrophilic statin group compared to the lipophilic statin group, which contradicts the direct anticancer benefits of lipophilic statins, but neither group reached statistical significance. Further studies analyzing statin usage and types with specific outcome measures such as cardiovascular events, duration of antiandrogen therapy, and adverse events related to ABI or ENZ will support in optimal therapy choices for mCRPC.

Characteristics and comorbidities of veterans treated with enzalutamide or abiraterone

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Background: Prostate cancer (PCa) is the most common male malignancy and is the fourth leading cause of cancer-related death in males worldwide. Enzalutamide (ENZ) and Abiraterone (AA) are used in the treatment of castrate resistant PCa after androgen deprivation therapy (ADT), however these agents have not been directly compared. These drugs have various adverse effects with different mechanisms of action and may be selected based on comorbid conditions. In this study, we aim to identify patient characteristics and comorbidities of patients treated with ENZ versus AA. Methods: Patients treated with AA or ENZ between September 10, 2014 and June 3, 2017 were identified in the Veterans Health Administration and followed until April 2020. Only patients with a pathologic diagnosis of PCa and treatment with ADT prior to AA or ENZ were included. Age at initiation of treatment, Elixhauser comorbidity score, PSA at initiation of AA or ENZ, Gleason score at diagnosis, treatment with ADT, docetaxel, and cabazitaxel was collected. Months of filled prescriptions were used to determine length of treatment. Results: Of 2575 patients, 1095 (42.5%) were initially treated with ENZ, 1480 (57.5%) with AA, and 1330 (51.7%) received both agents. Overall, 756 (29.4%) of patients were of black race. Docetaxel was used in 32.3% of patients and cabazitaxel in 11.7% of patients, with no differences between ENZ or AA cohorts. There were no significant differences in time from pathologic diagnosis to initial ADT therapy, or subsequently to treatment with ENZ or AA in either group. Furthermore, there were no differences in PSA (n = 1243, median AA 33.7 vs ENZ 30.7, p = 0.538) or Gleason scores (n = 1816, mean AA 7.85 vs ENZ 7.94, p = 0.142). Patients initially treated with ENZ compared to AA were older (mean 74.2 vs. 73.7 years, p = 0.032), had higher mean comorbidity score (7.1 vs. 6.7, p = 0.002), and had a longer duration of first treatment (median 10.5 months vs. 9.0 months, p < 0.001). As a second agent, ENZ also had a longer duration of treatment (median 5.0 vs. 4.2 months, p < 0.001). Patients treated initially with ENZ were more likely to have heart failure (18.2% vs. 13.7%, p = 0.002), cardiac arrhythmia (42.1% vs 36.6%, p = 0.004), valvular disease (13.7% vs 10.3%, p = 0.009), peripheral vascular disorders (26.8% vs 22.7%, p = 0.016), uncomplicated hypertension (86.8% vs 83.6%, p = 0.024), complicated hypertension (20.2% vs 16.9%, p = 0.033), uncomplicated diabetes (43.9% vs 37.4%, p = 0.001), complicated diabetes (26.0% vs 19.9%, p = 0.000), renal failure (28.3% vs 22.6%, p = 0.001). Conclusions: Overall, we found that patients initially treated with ENZ were older and had higher rates of cardiovascular disease and diabetes compared to those initially treated with AA. Assessment of comorbidities may be helpful in treatment selection to facilitate personalized medicine in prostate cancer, prevent adverse events, and improve outcomes.

Survival of veterans treated with enzalutamide and abiraterone in advanced prostate cancer

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Background: Abiraterone (AA) and enzalutamide (ENZ) are two second generation antiandrogens used to treat advanced prostate cancer, but no large head-to-head trials have been performed. These oral therapies are commonly used in older patients with medical comorbidities who are not candidates for chemotherapy or clinical trials and have different mechanisms of action, adverse events, and drug interactions. To understand survival of patients with prostate cancer, we studied United States veterans treated prior to approval of AA and ENZ for metastatic hormone sensitive prostate cancer when both drugs had approval for metastatic castration resistant prostate cancer. Methods: We identified patients treated with AA or ENZ between 9/10/2014 and 6/3/2017 in the Veterans Health Administration and followed them to April 2020. Age, Elixhauser comorbidity score, treatment with androgen deprivation therapy (ADT) and docetaxel were collected. Cox proportional hazards modeling was used to assess the association between first oral treatment (AA or ENZ) and overall survival, while adjusting for covariates. Results: Of 5895 patients, 2562 (43.5%) were initially treated with ENZ, 3333 (56.5%) with AA, and 3040 (51.6%) received only one of the two drugs during the study period. Patients initially treated with ENZ compared to AA were older (mean 75.9 vs. 75.0 years, p = 0.001), had higher mean comorbidity score (6.2 vs. 5.9, p < 0.001), and were less likely to receive both ENZ and AA (45.2% vs. 51.0%, p < 0.001) or docetaxel (24.1% vs. 28.4%, p < 0.001). Patients who received only AA or ENZ and never received docetaxel were older (mean 78.3 vs. 73.2 years, p < 0.001) with higher mean comorbidity scores (6.4 vs. 5.7, p < 0.001). In the entire cohort, initial treatment with ENZ was associated with longer median survival (24.1 vs. 22.2 months, p = 0.003). After adjusting for age and comorbidities, ENZ was associated with a decreased risk of death compared to AA (HR 0.87, 95% CI 0.82-0.92). In 3317 patients who received two or more therapies (ENZ, AA, docetaxel) there was no difference in median survival between initial treatment with ENZ or AA (28.0 vs. 27.9 months). In 2578 patients (43.7%) who never received docetaxel and either ENZ or AA only, median survival was longer in patients treated with ENZ (18.9 vs. 13.6 months, p < 0.001) and was associated with decreased mortality when adjusting for age and comorbidities (HR 0.73, 95% CI 0.67-0.80). Conclusions: In the overall cohort, initial treatment with ENZ was associated with increased survival compared to AA. Patients who received only ENZ or AA and never received docetaxel had the largest benefit from ENZ, a difference of 5.3 months median survival. Efforts should be made to improve therapy selection for patients with prostate cancer, especially older patients with comorbidities.

Herpes zoster in chronic lymphocytic leukemia: Effect of vaccination and treatment

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Background: Patients with Chronic Lymphocytic Leukemia (CLL) are susceptible to infections due to impaired humoral immunity as a complication of the disease, treatments received and age at diagnosis. Herpes zoster (HZ) is a painful, vesicular rash from reactivation of varicella-zoster virus that is common in immunocompromised patients. While HZ vaccines can reduce both varicella-zoster reactivation and post-herpetic neuralgia, vaccination rates are low. The aim of this study is to determine the effect of vaccination on rates of HZ infection in patients with CLL. Methods: We identified patients diagnosed with CLL between September 1999 and October 2015 using Veterans Administration Central Cancer Registry (VACCR). Pharmacy records were used to identify patients who received treatment for CLL and HZ. HZ events were defined as patients with International Classification of Diseases 9th Revision (ICD-9) codes for HZ infection (053) or prescriptions of acyclovir or valacyclovir at a dose of 1500 mg/day or higher or famciclovir at a dose of 1000 mg/day or higher without a diagnosis of Herpes simplex or Bell’s palsy, or an ICD-9 code and prescription above. Cox proportional hazards regression model was used to assess the association between vaccination as a time-varying exposure and developing HZ while controlling age at CLL diagnosis, co-morbidity score, and receipt of first and second line chemotherapy. The study was approved by the St. Louis VA Medical Center institutional review board. Results: A cohort of 7155 patients with CLL was identified using VACCR. 2640 patients (36.9%) and 1161 patients (16.2%) received first and second line chemotherapy respectively. Mean age at first chemotherapy was 69.5 years. We detected 1115 cases of HZ (15.6%) using ICD-9 codes, prescriptions or both. 615 patients (8.6%) received HZ vaccinations. Patients with HZ were younger (mean 68.0 vs. 69.8 years, p < 0.001), had similar co-morbidities, and were more likely to get treatment for CLL (58.1% vs. 33.0%, p < 0.001). Using a time-varying analysis, there was a trend for HZ vaccine to decrease the risk of developing HZ (HR 0.71, 95% CI 0.49-1.04, p = 0.082). When adjusting for age and co-morbidity, patients with CLL treated with first line chemotherapy had a higher risk of HZ (HR 2.34, 95% CI 2.02-2.71, p < 0.001) compared to those never receiving therapy. Second line chemotherapy increased risk of HZ (HR 1.32, 95% CI 1.13-1.55, p < 0.001) beyond first line treatment. Conclusions: HZ is prevalent in patients with CLL and affects younger patients who require chemotherapy. The risk of developing HZ increases in recipients of first and second line chemotherapy. In the time-varying analysis, there was a trend towards decreased infection in patients who received HZ vaccination. Further studies in a more modern cohort that assess infection risk using a larger vaccinated group with the newer and more effective HZ vaccine are warranted.

The First 2 Years of Biosimilar Epoetin for Cancer and Chemotherapy-Induced Anemia in the U.S.: A Review from the Southern Network on Adverse Reactions

Biosimilars are biologic drug products that are highly similar to reference products in analytic features, pharmacokinetics and pharmacodynamics, immunogenicity, safety, and efficacy. Biosimilar epoetin received Food and Drug Administration (FDA) approval in 2018. The manufacturer received an FDA nonapproval letter in 2017, despite receiving a favorable review by FDA's Oncologic Drugs Advisory Committee (ODAC) and an FDA nonapproval letter in 2015 for an earlier formulation. We discuss the 2018 FDA approval, the 2017 FDA ODAC Committee review, and the FDA complete response letters in 2015 and 2017; review concepts of litigation, naming, labeling, substitution, interchangeability, and pharmacovigilance; review European and U.S. oncology experiences with biosimilar epoetin; and review the safety of erythropoiesis-stimulating agents. In 2020, policy statements from AETNA, United Health Care, and Humana indicated that new epoetin oncology starts must be for biosimilar epoetin unless medical need for other epoetins is documented. Empirical studies report that as of 2012, reference epoetin use decreased from 40%-60% of all patients with cancer with chemotherapy-induced anemia to <5% of such patients because of safety concerns. Between 2018 and 2020, biosimilar epoetin use varied, increasing to 81% among one private insurer's patients covered by Medicare whose cancer care is administered with Oncology Analytics and to 41% with the same private insurer's patients with cancer covered by commercial health insurance and administered by the private insurer, to 0% in several Veterans Administration Hospitals, increasing to 100% in one large county hospital in California, and with yet-to-be-reported data from most oncology settings. We conclude that biosimilar epoetin appears to have overcome some barriers since 2015, although current uptake in the U.S. is variable. Pricing and safety considerations for all erythropoiesis-stimulating agents are primary determinants of biosimilar epoetin oncology uptake. IMPLICATIONS FOR PRACTICE: Few oncologists understand substitution and interchangeability of biosimilars with reference drugs. Epoetin biosimilar is new to the market, and physician and patient understanding is limited. The development of epoetin biosimilar is not familiar to oncologists.

Improving oncology biosimilar launches in the EU, the USA, and Japan: an updated Policy Review from the Southern Network on Adverse Reactions

The EU, the USA, and Japan account for the majority of biological pharmacotherapy use worldwide. Biosimilar regulatory approval pathways were authorised in the EU (2006), in Japan (2009), and in the USA (2015), to facilitate approval of biological drugs that are highly similar to reference products and to encourage market competition. Between 2007 and 2020, 33 biosimilars for oncology were approved by the European Medicines Agency (EMA), 16 by the US Food and Drug Administration (FDA), and ten by the Japan Pharmaceuticals and Medical Devices Agency (PMDA). Some of these approved applications were initially rejected because of manufacturing concerns (four of 36 [11%] with the EMA, seven of 16 [44%] with the FDA, none of ten for the PMDA). Median times from initial regulatory submission before approval of oncology biosimilars were 1·5 years (EMA), 1·3 years (FDA), and 0·9 years (PMDA). Pharmacists can substitute biosimilars for reference biologics in some EU countries, but not in the USA or Japan. US regulation prohibits substitution, unless the biosimilar has been approved as interchangeable, a designation not yet achieved for any biosimilar in the USA. Japan does not permit biosimilar substitution, as prescribers must include the product name on each prescription and that specific product must be given to the patient. Policy Reviews published in 2014 and 2016 in The Lancet Oncology focused on premarket and postmarket policies for oncology biosimilars before most of these drugs received regulatory approval. In this Policy Review from the Southern Network on Adverse Reactions, we identify factors preventing the effective launch of oncology biosimilars. Introduction to the market has been more challenging with therapeutic than for supportive care oncology biosimilars. Addressing region-specific competition barriers and educational needs would improve the regulatory approval process and market launches for these biologics, therefore expanding patient access to these products in the EU, the USA, and Japan.

Consequences to patients, clinicians, and manufacturers when very serious adverse drug reactions are identified (1997-2019): A qualitative analysis from the Southern Network on Adverse Reactions (SONAR)

BACKGROUND

Adverse drug/device reactions (ADRs) can result in severe patient harm. We define very serious ADRs as being associated with severe toxicity, as measured on the Common Toxicity Criteria Adverse Events (CTCAE)) scale, following use of drugs or devices with large sales, large financial settlements, and large numbers of injured persons. We report on impacts on patients, clinicians, and manufacturers following very serious ADR reporting.

METHODS

We reviewed clinician identified very serious ADRs published between 1997 and 2019. Drugs and devices associated with reports of very serious ADRs were identified. Included drugs or devices had market removal discussed at Food and Drug Advisory (FDA) Advisory Committee meetings, were published by clinicians, had sales > $1 billion, were associated with CTCAE Grade 4 or 5 toxicity effects, and had either >$1 billion in settlements or >1,000 injured patients. Data sources included journals, Congressional transcripts, and news reports. We reviewed data on: 1) timing of ADR reports, Boxed warnings, and product withdrawals, and 2) patient, clinician, and manufacturer impacts. Binomial analysis was used to compare sales pre- and post-FDA Advisory Committee meetings.

FINDINGS

Twenty very serious ADRs involved fifteen drugs and one device. Legal settlements totaled $38.4 billion for 753,900 injured persons. Eleven of 18 clinicians (61%) reported harms, including verbal threats from manufacturer (five) and loss of a faculty position (one). Annual sales decreased 94% from $29.1 billion pre-FDA meeting to $4.9 billion afterwards (p<0.0018). Manufacturers of four drugs paid $1.7 billion total in criminal fines for failing to inform the FDA and physicians about very serious ADRs. Following FDA approval, the median time to ADR reporting was 7.5 years (Interquartile range 3,13 years). Twelve drugs received Box warnings and one drug received a warning (median, 7.5 years following ADR reporting (IQR 5,11 years). Six drugs and 1 device were withdrawn from marketing (median, 5 years after ADR reporting (IQR 4,6 years)).

INTERPRETATION

Because very serious ADRs impacts are so large, policy makers should consider developing independently funded pharmacovigilance centers of excellence to assist with clinician investigations.

FUNDING

This work received support from the National Cancer Institute (1R01 CA102713 (CLB), https://www.nih.gov/about-nih/what-we-do/nih-almanac/national-cancer-institute-nci; and two Pilot Project grants from the American Cancer Society's Institutional Grant Award to the University of South Carolina (IRG-13-043-01) https://www.cancer.org/ (SH; BS).

Seven decades of chemotherapy clinical trials: a pan-cancer social network analysis

Clinical trials establish the standard of cancer care, yet the evolution and characteristics of the social dynamics between the people conducting this work remain understudied. We performed a social network analysis of authors publishing chemotherapy-based prospective trials from 1946 to 2018 to understand how social influences, including the role of gender, have influenced the growth and development of this network, which has expanded exponentially from fewer than 50 authors in 1946 to 29,197 in 2018. While 99.4% of authors were directly or indirectly connected by 2018, our results indicate a tendency to predominantly connect with others in the same or similar fields, as well as an increasing disparity in author impact and number of connections. Scale-free effects were evident, with small numbers of individuals having disproportionate impact. Women were under-represented and likelier to have lower impact, shorter productive periods (P < 0.001 for both comparisons), less centrality, and a greater proportion of co-authors in their same subspecialty. The past 30 years were characterized by a trend towards increased authorship by women, with new author parity anticipated in 2032. The network of cancer clinical trialists is best characterized as strategic or mixed-motive, with cooperative and competitive elements influencing its appearance. Network effects such as low centrality, which may limit access to high-profile individuals, likely contribute to the observed disparities.

Venous thromboembolism in multiple myeloma is associated with increased mortality

BACKGROUND

In multiple myeloma, venous thromboembolism (VTE) is common, and treatments for myeloma, such as lenalidomide, increase the risk of thrombosis while improving survival. The association between VTE and survival is not well known.

OBJECTIVES

To determine the association between VTE and survival in multiple myeloma (MM) while adjusting for known confounders that affect risk of thrombosis and survival, including patient characteristics and treatment in a retrospective cohort of US veterans.

PATIENTS/METHODS

A cohort of patients with newly diagnosed MM treated within Veterans Health Administration between September 1, 1999, and June 30, 2014, was created to assess the association between VTE and mortality using Cox proportional hazards regression modeling while accounting for known prognostic factors and treatments.

RESULTS

The cohort comprised 4446 patients with myeloma, including 2837 patients diagnosed after lenalidomide approval in July 2006. VTE occurred in 327 (7.4%) patients within 1 year and occurred at a median of 77 days (interquartile range, 37-153) after starting therapy for MM. In all patients, VTE was associated with increased mortality at 6 months (adjusted hazard ratio [aHR], 1.67; 95% confidence interval [CI], 1.18-2.37). Patients in the post-lenalidomide cohort with VTE had an increased mortality at both 6 months (aHR, 2.31; 95% CI, 1.52-3.51) and 12 months (aHR, 1.66; 95% CI, 1.19-2.33) after treatment initiation.

DISCUSSION

This study shows that VTE during the first 6-12 months of therapy is associated with increased mortality in patients with MM. Studies evaluating thromboprophylaxis in patients at high risk of thrombosis are needed.

End of an era of administering erythropoiesis stimulating agents among Veterans Administration cancer patients with chemotherapy-induced anemia

Erythropoisis stimulating agent (ESA) use was addressed in Food and Drug Administration (FDA) Oncology Drug Advisory Committee (ODAC) meetings between 2004 and 2008. FDA safety-focused regulatory actions occurred in 2007 and 2008. In 2007, black box warnings advised of early death and venous thromboembolism (VTE) risks with ESAs in oncology. In 2010, a Risk Evaluation Strategies (REMS) was initiated, with cancer patient consent that mortality and VTE risks were noted with ESAs. We report warnings and REMS impacts on ESA utilization among Veterans Administration (VA) cancer patients with chemotherapy-induced anemia (CIA). Data were from Veterans Affairs database (2003–2012). Epoetin and darbepoetin use were primary outcomes. Segmented linear regression was used to estimate changes in ESA use levels and trends, clinical appropriateness, and adverse events (VTEs) among chemotherapy-treated cancer patients. To estimate changes in level of drug prescription rate after policy actions, model-specific indicator variables as covariates based on specific actions were included. ESA use fell by 95% and 90% from 2005, for epoetin and darbepoetin, from 22% and 11%, respectively, to 1% and 1%, respectively, among cancer patients with CIA, respectively (p<0.01). Following REMS in 2010, mean hematocrit levels at ESA initiation decreased from 30% to 21% (p<0.01). Black box warnings preceded decreased ESA use among VA cancer patients with CIA. REMS was followed by reduced hematocrit levels at ESA initiation. Our findings contrast with privately- insured and Medicaid insured cancer patient data on chemotherapy-induced anemia where ESA use decreased to 3% to 7% by 2010–2012. By 2012, the era of ESA administration to VA to cancer patients had ended but the warnings remain relevant and significant. In 2019, oncology/hematology national guidelines (ASCO/ASH) recommend that cancer patients with chemotherapy-induced anemia should receive ESAs or red blood cell transfusions after risk-benefit evaluation.

Timing of US Food and Drug Administration (FDA) cancer drug approvals relative to publication of clinical trial results

2071

Background: Publication of clinical trial results in peer reviewed literature is essential to inform clinicians regarding the use of new anti-cancer treatments, which often have a low therapeutic ratio and require careful assessment of risks and benefits. Publication of registration trials should precede FDA approval to facilitate evaluation and implementation of new therapies. The timing of trial publication relative to FDA drug approvals has not been systematically investigated. Methods: We collected all FDA drug approvals for a cancer indication between 2000-19. Trials were identified using FDA labels as well as drugs and publications indexed on HemOnc.org. Approvals for generics/biosimilars, non-oncology indications and label revisions without supportive evidence were excluded. Dates of approval, the approval pathway, approval type (new vs expansion), and the first full publication related to the registration were recorded. Trials and approvals were matched using available metadata. We calculated the proportion of drugs approved prior to publication overall and for those receiving accelerated approval (AA). We used logistic regression to compare rates of pre-publication approval by approval pathway and by new vs expanded approval. Results: Among a total of 378 drug approvals, 139 (37%) had pre-publication approval. Of these, the median overall time from approval to publication was 140 days (IQR 64-281 days). For those with approval after publication, median time from publication to approval was 157 days (IQR 72-359 days). The number of drugs approved pre-publication rose by 27% between the first and last quarters of the study period, though, the proportion decreased as more anti-cancer drugs have been approved in recent years (Table). More drugs were approved pre-publication through AA than regular approval (46% vs 34%, OR 1.66 [95% CI 1.03-2.70], p=0.04) and as new approvals vs. expanded approvals (45% vs 32%, OR 1.76 [95% CI 1.15-2.70], p=0.01). Conclusions: A substantial minority of FDA approvals occur before trial results are published, with the odds being higher for drugs receiving AA and for new approvals. Since clinicians rely upon published results to inform risk/benefit decisions, efforts are needed to ensure trial results are published by the time of FDA approval of new cancer drugs and indications. [Table: see text]

Mismatch between mortality burden and number of FDA registration trials in highly lethal cancers

2072

Background: Treatment successes in cancer are achieved through new drugs tested in clinical trials. However, drug discovery has been disparate across cancer types for various reasons. We sought to investigate if the number of trials used to support United States Food and Drug Administration (FDA) drug approvals is proportional to the incidence and mortality burden of highly lethal cancers, i.e. those with an expected relative mortality of >5% per Cancer Statistics, 2020 (Siegel et al.). Methods: All FDA labels for 258 antineoplastic cancer drugs approved as of January 2020 were reviewed for citations of registration trials supporting initial approval and additional indications. Trials were identified by matching described characteristics (e.g., patients enrolled, clinical trial NCT codes) to publications indexed on HemOnc.org. Trials were labeled by cancer type studied and type of trial (randomized vs non-randomized). Results: We identified 559 registration trials in total. Results for the six highly lethal cancers are shown in the table. The percent of registration trials was roughly proportional to incidence, but not mortality burden. For example, despite the 22% expected mortality burden of lung cancer, it had a share of only 11% of registration trials whereas breast cancer has an expected 7% mortality burden, with a share of 14% of registration trials. Chronic myeloid leukemia is expected to cause 1,130 deaths in 2020 (0.2%) and has had 20 registration trials (3.6%). The highly lethal cancers had a higher rate of randomized trials supporting approval than other cancers (84% vs 56%, p<0.001 [Chi-square]). Conclusions: While the findings may in part be due to disease biology (e.g., pancreatic ductal adenocarcinoma has proven resistant to many novel therapies), our evaluation highlights a potential mismatch between resources and needs. Randomized trials were more often used to support new drug approvals in highly lethal cancers. These findings will be important in regulatory policy. [Table: see text]

End of an era for erythropoiesis-stimulating agents in oncology

Erythropoiesis-stimulating agents (ESAs) are available to treat chemotherapy-induced anemia (CIA). In 2007-2008, regulatory notifications advised of venous thromboembolism and mortality risks while the Center for Medicare and Medicaid Services' restricted ESA initiation to patients with hemoglobin <10 g/dl. In 2010, a Risk Evaluation and Mitigation Strategies required consent prior to administration. We evaluated ESA utilization from 2003 to 2012 and obtained private health insurer claims data for persons with lung, colorectal, or breast cancer from 2001 to 2012. ESA use for CIA was determined by an ESA claim after chemotherapy, up to 6 months after treatment. We identified 839,948 commercially insured patients, including 24,785 patients with ESA-treated CIA (3.2%). Darbepoetin use increased 3.9-fold from 2003 to 2007 (12.3% to 48.7%) and then decreased 95% to 2.6% by 2012. Epoetin use decreased 90% from 2003 to 2012 (30.3% to 3.1%). Between 2003 and 2012, mean epoetin dosing decreased 0.8-fold (244,979 in 2003 vs. 196,216 units in 2012), but increased 1.8-fold for darbepoetin-treated CIA (262 in 2003 to 467 μg in 2012). Among CIA patients, transfusions were low (4.5%) in 2002-2007, then increased 2.2-fold between 2008 and 2012. Safety initiatives between 2007 and 2010 facilitated reductions in ESA use combined with changes in coverage. These data show the efficacy of regulatory efforts, publication of adverse events and changes in reimbursement in reducing use of ESAs. Future studies are warranted to optimize deimplementation strategies to improve patient safety.