Addressing racial disparities in prostate cancer pathology prediction models: external validation and comparison of four models of pathological outcome prediction before radical prostatectomy in the multiethnic SEARCH cohort

BACKGROUND

Certain widely used pathological outcome prediction models that were developed in tertiary centers tend to overpredict outcomes in the community setting; thus, the Michigan Urological-Surgery Improvement Collaborative (MUSIC) model was developed in general urology practice to address this issue. Additionally, the development of these models involved a relatively small proportion of Black men, potentially compromising the accuracy of predictions in this patient group. We tested the validity of the MUSIC and three widely used nomograms to compare their overall and race-stratified predictive performance.

METHODS

We extracted data from 4139 (1138 Black) men from the Shared Equal Access Regional Cancer Hospital (SEARCH) database of the Veterans Affairs health system. The predictive performance of the MUSIC model was compared to the Memorial-Sloan Kettering (MSK), Briganti-2012, and Partin-2017 models for predicting lymph-node invasion (LNI), extra-prostatic extension (EPE), and seminal vesicle invasion (SVI).

RESULTS

The median PSA of Black men was higher than White men (7.8 vs. 6.8 ng/ml), although they were younger by a median of three years and presented at a lower-stage disease. MUSIC model showed comparable discriminatory capacity (AUC:77.0%) compared to MSK (79.2%), Partin-2017 (74.6%), and Briganti-2012 (76.3%), with better calibration for LNI. AUCs for EPE and SVI were 72.7% and 76.9%, respectively, all comparable to the MSK and Partin models. LNI AUCs for Black and White men were 69.6% and 79.6%, respectively, while EPE and SVI AUCs were comparable between races. EPE and LNI had worse calibration in Black men. Decision curve analysis showed MUSIC superiority over the MSK model in predicting LNI, especially among Black men.

CONCLUSION

Although the discriminatory performance of all models was comparable for each outcome, the MUSIC model exhibited superior net benefit to the MSK model in predicting LNI outcomes among Black men in the SEARCH population.

Do Hispanic Puerto Rican men have worse outcomes after radical prostatectomy? Results from SEARCH

BACKGROUND

We previously reported that outcomes after radical prostatectomy (RP) were similar among non-Hispanic Black, non-Hispanic White, and Hispanic White Veterans Affairs (VA) patients. However, prostate cancer (PC) mortality in Puerto Rican Hispanics (PRH) may be higher than in other Hispanic groups. Data focused on PRH patients is sparse; thus, we tested the association between PR ethnicity and outcomes after RP.

METHODS

Analysis included men in SEARCH cohort who underwent RP (1988-2020, n = 8311). PRH patients (n = 642) were treated at the PR VA, and outcomes were compared to patients treated in the Continental US regardless of race. Logistic regression was used to test the associations between PRH and PC aggressiveness, adjusting for demographic and clinicopathological features. Multivariable Cox models were used to investigate PRH versus Continental differences in biochemical recurrence (BCR), metastases, castration-resistant PC (CRPC), and PC-specific mortality (PCSM).

RESULTS

Compared to Continental patients, PRH patients had lower adjusted odds of pathological grade group ≥2 (p < 0.001), lymph node metastasis (p < 0.001), and positive margins (p < 0.001). In contrast, PRH patients had higher odds of extracapsular extension (p < 0.001). In Cox models, PRH patients had a higher risk for BCR (HR = 1.27, p < 0.001), metastases (HR = 1.49, p = 0.014), CRPC (HR = 1.80, p = 0.001), and PCSM (HR = 1.74, p = 0.011). Further adjustment for extracapsular extension and other pathological variables strengthened these findings.

CONCLUSIONS

In an equal access setting, PRH RP patients generally had better pathological features, but despite this, they had significantly worse post-treatment outcomes than men from the Continental US, regardless of race. The reasons for the poorer prognosis among PRH men require further research.

Prototype Description and Ex Vivo Evaluation of a System for Combined Endorectal Magnetic Resonance Imaging and In-Bore Biopsy of the Prostate

ABSTRACT

We describe early ex vivo proof-of-concept testing of a novel system composed of a disposable endorectal coil and converging multichannel needle guide with a reusable clamp stand, embedded electronics, and baseplate to allow for endorectal magnetic resonance (MR) imaging and in-bore MRI-targeted biopsy of the prostate as a single integrated procedure. Using prostate phantoms imaged with standard T2-weighted sequences in a Siemens 3T Prisma MR scanner, we measured the signal-to-noise ratio in successive 1-cm distances from the novel coil and from a commercially available inflatable balloon coil and measured the lateral and longitudinal deviation of the tip of a deployed MR compatible needle from the intended target point. Signal-to-noise ratio obtained with the novel system was significantly better than the inflatable balloon coil at each of five 1-cm intervals, with a mean improvement of 78% (P < 0.05). In a representative sampling of 15 guidance channels, the mean lateral deviation for MR imaging-guided needle positioning was 1.7 mm and the mean longitudinal deviation was 2.0 mm. Our ex vivo results suggest that our novel system provides significantly improved signal-to-noise ratio when compared with an inflatable balloon coil and is capable of accurate MRI-guided needle deployment.

Are associations between obesity and prostate cancer outcomes following radical prostatectomy the same in smokers and non-smokers? Results from the SEARCH Cohort

PURPOSE

Obesity and smoking have been associated with poor prostate cancer (PC) outcomes. We investigated associations between obesity and biochemical recurrence (BCR), metastasis, castrate resistant-PC (CRPC), PC-specific mortality (PCSM), and all-cause mortality (ACM) and examined if smoking modified these associations.

METHODS

We analyzed SEARCH Cohort data from men undergoing RP between 1990 and 2020. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between body mass index (BMI) as a continuous variable and weight status classifications (normal: 18.5 ≤ 25 kg/m2; overweight: 25-29.9 kg/m2; obese: ≥ 30 kg/m2) and PC outcomes.

RESULTS

Among 6,241 men, 1,326 (21%) were normal weight, 2,756 (44%) overweight and 2159 (35%) obese; 1,841 (30%) were never-smokers, 2,768 (44%) former and 1,632 (26%) current-smokers. Among all men, obesity was associated with non-significant increased risk of PCSM, adj-HR = 1.71; 0.98-2.98, P = 0.057, while overweight and obesity were inversely associated with ACM, adj-HR = 0.75; 0.66-0.84, P < 0.001 and adj-HR = 0.86; 0.75-0.99, P = 0.033, respectively. Other associations were null. BCR and ACM were stratified for smoking status given evidence for interactions (P = 0.048 and P = 0.054, respectively). Among current-smokers, overweight was associated with an increase in BCR (adj-HR = 1.30; 1.07-1.60, P = 0.011) and a decrease in ACM (adj-HR = 0.70; 0.58-0.84, P < 0.001). Among never-smokers, BMI (continuous) was associated with an increase in ACM (adj-HR = 1.03; 1.00-1.06, P = 0.033).

CONCLUSIONS

While our results are consistent with obesity as a risk factor for PCSM, we present evidence of effect modification by smoking for BCR and ACM highlighting the importance of stratifying by smoking status to better understand associations with body weight.

Diabetes and Prostate Cancer Outcomes in Men with Nonmetastatic Castration-Resistant Prostate Cancer: Results from the SEARCH Cohort

BACKGROUND

The prognosis of diabetic men with advanced prostate cancer is poorly understood and understudied. Hence, we studied associations between diabetes and progression to metastases, prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM) in men with nonmetastatic castration-resistant prostate cancer (nmCRPC).

METHODS

Data from men diagnosed with nmCRPC between 2000 and 2017 at 8 Veterans Affairs Health Care Centers were analyzed using Cox regression to determine HRs and 95% confidence intervals (CI) for associations between diabetes and outcomes. Men with diabetes were classified according to: (i) ICD-9/10 codes only, (ii) two HbA1c values > 6.4% (missing ICD-9/10 codes), and (iii) all diabetic men [(i) and (ii) combined].

RESULTS

Of 976 men (median age: 76 years), 304 (31%) had diabetes at nmCRPC diagnosis, of whom 51% had ICD-9/10 codes. During a median follow-up of 6.5 years, 613 men were diagnosed with metastases, and 482 PCSM and 741 ACM events occurred. In multivariable-adjusted models, ICD-9/10 code-identified diabetes was inversely associated with PCSM (HR, 0.67; 95% CI, 0.48-0.92) while diabetes identified by high HbA1c values (no ICD-9/10 codes) was associated with an increase in ACM (HR, 1.41; 95% CI, 1.16-1.72). Duration of diabetes, prior to CRPC diagnosis was inversely associated with PCSM among men identified by ICD-9/10 codes and/or HbA1c values (HR, 0.93; 95% CI, 0.88-0.98).

CONCLUSIONS

In men with late-stage prostate cancer, ICD-9/10 'code-identified' diabetes is associated with better overall survival than 'undiagnosed' diabetes identified by high HbA1c values only.

IMPACT

Our data suggest that better diabetes detection and management may improve survival in late-stage prostate cancer.

A modeling study to estimate prostate cancer-specific mortality on active surveillance for men with favorable intermediate-risk prostate cancer: Results from the SEARCH cohort

PURPOSE

Limited data exist to help surgeons decide between active surveillance (AS) versus treatment for men with favorable intermediate risk (FIR) prostate cancer. To estimate the theoretical excess risk of prostate cancer-specific mortality (PCSM) with AS versus radical prostatectomy (RP), we determined the risk of PCSM in FIR men undergoing RP and modeled the PCSM risk for AS using a range of increased PSCM scenarios ranging from 1.25x to 2x higher relative to RP.

MATERIALS AND METHODS

We retrospectively reviewed data from men undergoing RP from 1988 to 2017 at 8 Veterans Affairs hospitals within the SEARCH cohort. Men with FIR PC were identified using the NCCN risk criteria. Risk of PCSM at 5, 10, and 15 years after RP was estimated. Using these estimates, PCSM was then modeled for AS using a range of increased risk of PCSM relative to RP ranging from 1.25x to 2x higher.

RESULTS

For the 920 FIR men identified, 5-, 10-, and 15-year survival estimates for PCSM after RP were 99.9%, 99.0%, and 97.8%, respectively. If the risk of PCSM on AS were 1.25-2x greater than RP, there would be 0.54%-2.17% excess risk of PCSM at 15 years.

CONCLUSIONS

The risk of death for FIR after RP is very low. Assuming even modestly increased PCSM with AS versus RP, the excess risk of death for AS in FIR is low even up to 15 years. These data support the consideration of AS as a relatively safe alternative to RP in FIR men, though prospective randomized trials are needed to validate these findings.

Radium-223 Utilization Patterns and Outcomes in Clinical Practice

INTRODUCTION

Radium-223 was approved for metastatic castration-resistant prostate cancer based on the ALSYMPCA trial. We characterize radium-223 treatment patterns and overall survival (OS) in a large equal access health system.

METHODS

We identified all men within the Veterans Affairs (VA) Healthcare System who received radium-223 between January 2013 and September 2017. Patients were followed until death or last followup. We abstracted all treatments received prior to radium; no treatments after radium were abstracted. Our primary aim was understanding practice patterns, and secondary outcome was the association between treatment pattern and OS measured using Cox models.

RESULTS

We identified 318 bone metastatic castration-resistant prostate cancer patients who received radium-223 within the VA Healthcare System. Of these patients 277 (87%) died during followup. The 5 predominant treatment patterns that encompassed 88% of patients (279/318) were 1) androgen receptor-targeted agent (ARTA)-radium, 2) docetaxel-ARTA-radium, 3) ARTA-docetaxel-radium, 4) docetaxel-ARTA-cabazitaxel-radium and 5) radium alone. Median OS was 11 months (95% CI 9.7-12.5). Men who received ARTA-docetaxel-radium had the worst survival. All other treatments had similar outcomes. Only 42% of patients completed the full 6 injections; 25% received only 1 or 2 injections.

CONCLUSIONS

We identified the most common radium-223 treatment patterns and their association with OS within the VA population. The better survival in ALSYMPCA (14.9 months) vs our study (11 months) along with 58% of patients not receiving the full radium-223 course suggests radium is being used later in the disease course in the real world in a more heterogeneous population.

Selecting patients for magnetic resonance imaging cognitive versus ultrasound fusion biopsy of the prostate: A within‐patient comparison

Objectives

To compare overall agreement between magnetic resonance imaging (MRI)–ultrasound (US) fusion biopsy (FB) and MRI cognitive fusion biopsy (CB) of the prostate and determine which factors affect agreement for prostate cancer (PCa) who underwent both modalities in a prospective within‐patient protocol.

Patients and Methods

From August 2017 to January 2021, patients with at least one Prostate Imaging Reporting & Data System (PI‐RADS) 3 or higher lesion on multiparametric MRI underwent transrectal FB and CB in a prospective within‐patient protocol. CB was performed for each region of interest (ROI), followed by FB, followed by standard 12 core biopsy. Patients who were not on active surveillance were analysed. The primary endpoint was agreement for any PCa detection. McNemar's test and kappa statistic were used to analyse agreement. Chi‐square test, Fisher's exact test and Wilcoxon rank sum test were used to analyse disagreement across clinical and MRI spatial variables. A multivariable generalized mixed‐effect model was used to compare the interaction between select variables and fusion modality. Statistics were performed using SAS and R.

Results

Ninety patients and 98 lesions were included in the analysis. There was moderate agreement between FB and CB (k = 0.715). McNemar's test was insignificant (p = 0.285). Anterior location was the only variable associated with a significant variation in agreement, which was 70% for anterior lesions versus 89.7% for non‐anterior lesions (p = 0.035). Discordance did not vary significantly across other variables. In a mixed‐effect model, the interaction between anterior location and use of FB was insignificant (p = 0.411).

Conclusion

In a within‐patient protocol of patients not on active surveillance, FB and CB performed similarly for PCa detection and with moderate agreement. Anterior location was associated with significantly higher disagreement, whereas other patient and lesion characteristics were not. Additional studies are needed to determine optimal biopsy technique for sampling anterior ROI.

Red Blood Cell Distribution Width Is Associated with All-cause Mortality but Not Adverse Cancer-specific Outcomes in Men with Clinically Localized Prostate Cancer Treated with Radical Prostatectomy: Findings Based on a Multicenter Shared Equal Access Regional Cancer Hospital Registry

Background

Recent reports with a small number of patients showed an association of red blood cell distribution width (RDW) with prostate cancer (PCa) progression.

Objective

To investigate whether preoperative RDW can serve as a prognostic marker in patients with PCa undergoing radical prostatectomy (RP) in a large, equal access, and diverse patient cohort.

Design, setting, and participants

Data were retrospectively collected on 4756 men treated with RP at eight Veteran Affairs medical centers within the Shared Equal Access Regional Cancer Hospital (SEARCH) database from 1999 through 2017.

Outcome measurements and statistical analysis

Biochemical recurrence (BCR) was the primary outcome, while metastasis, all-cause mortality (ACM), and prostate cancer–specific mortality (PCSM) were secondary outcomes.

Results and limitations

The mean (standard deviation) age was 62 yr (6.1), and 1589 (33%) men were black. The median (interquartile range) follow-up was 82 mo (46–127). Preoperative RDW either as a continuous variable or when stratified by quartiles was not associated with BCR. Likewise, preoperative RDW was not associated with metastases or PCSM. However, higher RDW was significantly associated with higher ACM, both as a continuous variable (p < 0.001) and when stratified by quartiles in univariable and multivariable models (p < 0.001). RDW was found to be correlated with D’Amico risk classification of PCa. Study limitations include its retrospective nature and lack of data regarding advanced PCa.

Conclusions

Preoperative RDW was not associated with PCa outcomes in men treated with RP but was associated with ACM. While RDW may be a biomarker of overall health, it is not a biomarker for PCa outcomes. These results emphasize the importance of diverse, larger sized studies in genitourinary cancer research.

Patient summary

Prostate cancer includes a wide spectrum of diseases with different genetic, pathological, and oncological behaviors. Red blood cell distribution width is helpful in predicting the overall survival for a localized prostate cancer patient, and hence, it can help inform personalized treatment decisions and operative care.

A randomized, controlled trial of group exercise training for fall prevention and functional improvements during and after treatment for prostate cancer

TPS193

Background: Many prostate cancer survivors are treated with androgen deprivation therapy (ADT), but these therapies may increase frailty, worsen physical functioning, and increase fall risk. While exercise may counter functional declines associated with ADT, no studies have tested whether and which type of exercise may reduce falls and frailty. The purpose of this trial is to compare the relative efficacy of strength training versus tai ji quan training against each other and to a stretching control group on falls, frailty and physical functioning in men expose to ADT for prostate cancer. Methods: Prostate cancer survivors treated with ADT (n = 360) will be recruited to participate in this single-blind, parallel group, randomized trial. To be eligible men must meet the following criteria: 1) histologically confirmed prostate cancer, 2) received at least 6 months of ADT within the past 10 years, 3) report >1 fall in the past year OR have a score on one of two physical performance tests that is associated with increased fall risk (i.e. ≥ 12.0 seconds to complete the 3 meter timed up and go (TUG), or ≥ 10.0 seconds to complete 5 chair stands), 4) completed any other treatment at least 6 weeks prior to enrollment and not be on any concurrent prostate cancer therapy besides ADT, 5) not currently participating in moderate-vigorous intensity lower-body strength training or tai ji quan training ≥ 2 times/week for ≥ 30 minutes per session, 6) no cognitive difficulties that limit ability to answer survey questions or participate in exercise classes and performance tests, 7) no medical condition, disorder, or take medication that contraindicates participation in moderate intensity exercise, and 8) are able to communicate in English. Participants will be randomized to one of three supervised, group training programs: i) strength training, ii) tai ji quan training, or iii) stretching (control), that train 3x/week for 6 months. Outcomes are assessed at baseline, 3 (mid-intervention), 6 (immediately post-intervention) and 12 (follow-up) months. The primary outcome is falls assessed by monthly self-report. Secondary outcomes include the following: Frailty (low lean body mass (by bioelectrical impedance analysis), exhaustion (by SF-36 vitality scale), low activity (by CHAMPS physical activity survey), slowness (by 4m usual walk speed), and weakness (by chair stand time)); Objective and subjective measures of physical function will also be collected. Negative binomial regression models will be used to assess differences in falls between groups, while mixed-effects modeling will be used to compare the relative efficacy of training group on secondary outcomes. Registered November 18, 2018. Clinical trial information: NCT03741335.

Characteristics of prostate cancer survivors exposed to ADT and enrolled in a fall prevention exercise trial: Comparison of men with confirmed fall history to men with fall risk factors

81

Background: Androgen deprivation therapy (ADT) for prostate cancer may result in accelerated aging that increases the risk for falls. Falls are higher in men with a history of ADT use, even if treatment is discontinued, compared to men never on ADT. Less is known, however, about the specific patient characteristics that might be associated with falls. Methods: We analyzed data from prostate cancer survivors with a history of ADT and who had enrolled in an ongoing NIH-funded fall prevention exercise trial (NCT03741335). To be eligible for the trial, men were 1) currently or previously treated with ADT and 2) reported a fall in the previous 6 months or had evidence of fall risk. Fall risk was assessed through slow times on a 5 time sit-to-stand test (5XSTS; sec) or timed up and go walk test (TUG; sec). For this analysis we compared men with a positive fall history to men with no recent falls but evidence of fall risk. We compared age, ADT history (past vs current), body mass index (BMI), self-report comorbidities from the Charlson Comorbidity Index, physical function and disability from the LLFDI, pain from the BPI, anxiety from PROMIS, depressive symptoms from the CES-D, fear of falling and activity restrictions from the SAFFE, and physical activity from CHAMPS, as well as objective measures of strength and mobility using 5XSTS and TUG. Results: A total of 171 cases (mean age 73.1 +/- 7.1 years of age) were available for analysis, with 58 men (34%) reporting a fall in the 6 months prior to enrollment. Of reported falls, 11% were injurious falls, with 4% requiring medical attention. Injuries included fractures (n = 4), head injury (n = 2), joint injury (n = 3), and bruises/scrapes (n = 8). Fallers reported significantly lower levels of physical functioning (p < 0.001), greater levels of disability (p < 0.01), greater fear of falling (p < 0.001), more activity restrictions due to falls worry (p < 0.02) and slower TUG times (p < 0.03), than men who had not recently fallen. There were no significant differences between men with established fall history and men with fall risk only on age, ADT history, comorbidities, BMI, pain, anxiety, depressive symptoms, physical activity, or 5XSTS (p for all > 0.05). Conclusions: Among our preliminary sample of men with a history of ADT use and enrolled in an ongoing fall prevention trial, men with an established fall history functioned less independently, were more worried about falls and apt to restrict their activities accordingly, and had poorer mobility than men who hadn’t recently fallen. From our cross-sectional design we cannot determine whether poorer functioning and mobility and greater fear of falling were antecedents or consequences of a recent fall. Regardless, interventions designed to prevent falls in men exposed to ADT are critical to prevent potential injurious falls and to keep men functioning independently.

Prostate weight and prostate cancer outcomes after radical prostatectomy: Results from the SEARCH cohort study

BACKGROUND

Smaller prostates have been linked to unfavorable clinical characteristics and poor short-term outcomes following radical prostatectomy (RP). We examined the relation between prostate weight at RP and prostate cancer (PC) outcomes post-RP.

METHODS

Men in the SEARCH cohort undergoing RP between 1988 and 2017 (N = 6242) were studied for PC-specific mortality (PCSM) as the primary outcome, and for biochemical recurrence (BCR), castration-resistant PC (CRPC) and metastasis as secondary outcomes. Hazard ratios (HR) and 95% confidence intervals (CI) were determined for associations between prostate weight and outcomes using Fine-Gray competing risk regression multivariable analyses. Sensitivity analyses were also carried out following exclusion of: (i) men with extreme prostate weights (<20 g and ≥100 g); and (ii) men with elevated prostate specific antigen (PSA) levels.

RESULTS

Median values for age, pre-RP PSA and prostate weight were 63 years, 6.6 ng/ml, and 42.0 g, respectively. During a median follow-up of 7.9 years, 153 (3%) died from PC, 2103 (34%) had BCR, 203 (3%) developed CRPC, and 289 (5%) developed metastases. Prostate weight was not associated with PCSM in the main analyses (multivariable HR = 1.43; 95% CI: 0.87-2.34) or in sensitivity analyses. Prostate weight was inversely associated with BCR in the main analyses (multivariable HR = 0.70; 95%CI: 0.61-0.79) which was unchanged in sensitivity analyses. HRs for prostate weight and CRPC and metastasis were elevated but statistical significance was not attained. Similar results were observed in sensitivity analyses.

CONCLUSIONS

Inconsistent results for prostate weight and short-term vs longer-term outcomes highlight the need to better understand the complex biology leading to prostate size and the relevance of prostate size as a predictor of PC outcomes.

Genetic Factors Associated with Prostate Cancer Conversion from Active Surveillance to Treatment

Men diagnosed with low-risk prostate cancer (PC) are increasingly electing active surveillance (AS) as their initial management strategy. While this may reduce the side effects of treatment for prostate cancer, many men on AS eventually convert to active treatment. PC is one of the most heritable cancers, and genetic factors that predispose to aggressive tumors may help distinguish men who are more likely to discontinue AS. To investigate this, we undertook a multi-institutional genome-wide association study (GWAS) of 5,222 PC patients and 1,139 other patients from replication cohorts, all of whom initially elected AS and were followed over time for the potential outcome of conversion from AS to active treatment. In the GWAS we detected 18 variants associated with conversion, 15 of which were not previously associated with PC risk. With a transcriptome-wide association study (TWAS), we found two genes associated with conversion (MAST3, p = 6.9×10-7 and GAB2, p = 2.0×10-6). Moreover, increasing values of a previously validated 269-variant genetic risk score (GRS) for PC was positively associated with conversion (e.g., comparing the highest to the two middle deciles gave a hazard ratio [HR] = 1.13; 95% Confidence Interval [CI]= 0.94-1.36); whereas, decreasing values of a 36-variant GRS for prostate-specific antigen (PSA) levels were positively associated with conversion (e.g., comparing the lowest to the two middle deciles gave a HR = 1.25; 95% CI, 1.04-1.50). These results suggest that germline genetics may help inform and individualize the decision of AS-or the intensity of monitoring on AS-versus treatment for the initial management of patients with low-risk PC.

Addressing Burnout in Urology: A Qualitative Assessment of Interventions

INTRODUCTION

We characterized physician burnout among urologists to determine the prevalence and efficacy of specific burnout interventions utilized and to determine involvement of workplaces in effective burnout interventions.

METHODS

The Western Section of the American Urological Association created an electronic, 29 question workforce survey. Several questions focused on assessing the level of urologist burnout, prevalence of work sponsored burnout interventions and efficacy of specific interventions.

RESULTS

A total of 440 responses were received (25.9% response rate); 82.2% of responders were male. The majority of urologists noted some level of burnout (79.5%) with no significant difference between those who reported no burnout vs some level of burnout (p=0.30). The most commonly tried interventions to reduce burnout were participating in regular physical exercise (76.6%), reading nonmedical literature (67.1%) and decreasing or modifying work hours (52.3%). The interventions most frequently cited as "very effective" were hiring a scribe (62.5%), regular exercise (56.1%) and participating in 1-on-1 gatherings with colleagues outside of work (44.6%). There were no significant differences noted when comparing "very effective" interventions by gender. The interventions most frequently cited as not effective were stress or burnout seminars (26.9%) and meditation/mindfulness training (11.5%); 42.5% reported workplace interventions to help prevent or reduce burnout.

CONCLUSIONS

Certain practice-changing and personal burnout interventions were noted to be "very effective" in decreasing burnout. Fewer than half of responders noted workplace sponsorship of interventions. Organizational support may lead to increased participation and effectiveness of burnout interventions.

Safety of concomitant therapy with radium-223 and abiraterone or enzalutamide in a real-world population

BACKGROUND

Real-world utilization and outcomes of combination therapy for men with metastatic castrate-resistant prostate cancer (mCRPC) are largely unknown. We evaluated the overall survival (OS) and skeletal-related events (SREs) among men who received radium-223 with or without concomitant abiraterone or enzalutamide in the Veterans Affairs (VA) Health System.

METHODS

We reviewed charts of all mCRPC patients who received radium-223 in the VA from January 2013 to September 2017. We used Cox models to test the association between concomitant therapy versus radium-223 alone on OS and SRE. Sensitivity analyses were performed for concomitant use of denosumab/bisphosphonates.

RESULTS

Three hundred and eighteen patients treated with radium-223 were identified; 116/318 (37%) received concomitant abiraterone/enzalutamide. Two hundred and seventy-seven (87%) patients died during follow-up. Patients who received concomitant therapy were younger at radium-223 initiation (median age 68 vs. 70, p = .027) and had a longer follow-up (median 29.5 vs. 17.9 months, p = .030). There was no OS benefit for those on concomitant therapy (hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.67-1.12, p = .28). There was a trend for an increased SRE risk for patients on concomitant therapy (HR: 1.87, 95% CI: 0.96-3.61, p = .066), but this was not significant. When analyses were limited to men using bone heath agents, similar results were seen for OS (HR: 0.86, 95% CI 0.64-1.15, p = .30) and SRE (HR: 2.36, 95% CI: 0.94-5.94, p = .068).

CONCLUSIONS

Despite the common use of concomitant therapy in this real-world study, there was no difference in OS among mCRPC patients. A nonsignificant increased SRE risk was observed. Further work needs to evaluate the optimal sequence, timing, and safety of combination therapies.

Diabetes and Prostate Cancer Outcomes in Obese and Nonobese Men After Radical Prostatectomy

Background

The link between diabetes and prostate cancer progression is poorly understood and complicated by obesity. We investigated associations between diabetes and prostate cancer-specific mortality (PCSM), castrate-resistant prostate cancer (CRPC), and metastases in obese and nonobese men undergoing radical prostatectomy (RP).

Methods

We included 4688 men from the Shared Equal Access Regional Cancer Hospital cohort of men undergoing RP from 1988 to 2017. Diabetes prior to RP, anthropometric, and clinical data were abstracted from 6 Veterans Affairs Medical Centers electronic medical records. Primary and secondary outcomes were PCSM and metastases and CRPC, respectively. Multivariable-adjusted hazard ratios (adj-HRs) and 95% confidence intervals (CIs) were estimated for diabetes and PCSM, CRPC, and metastases. Adjusted hazard ratios were also estimated in analyses stratified by obesity (body mass index: nonobese <30 kg/m²; obese ≥30 kg/m²). All statistical tests were 2-sided.

Results

Diabetes was not associated with PCSM (adj-HR = 1.38, 95% CI = 0.86 to 2.24), CRPC (adj-HR = 1.05, 95% CI = 0.67 to 1.64), or metastases (adj-HR = 1.01, 95% CI = 0.70 to 1.46), among all men. Interaction terms for diabetes and obesity were statistically significant in multivariable models for PCSM, CRPC, and metastases (P ≤ .04). In stratified analyses, in obese men, diabetes was associated with PCSM (adj-HR = 3.06, 95% CI = 1.40 to 6.69), CRPC (adj-HR = 2.14, 95% CI = 1.11 to 4.15), and metastases (adj-HR = 1.57, 95% CI = 0.88 to 2.78), though not statistically significant for metastases. In nonobese men, inverse associations were suggested for diabetes and prostate cancer outcomes without reaching statistical significance.

Conclusions

Diabetes was associated with increased risks of prostate cancer progression and mortality among obese men but not among nonobese men, highlighting the importance of aggressively curtailing the increasing prevalence of obesity in prostate cancer survivors.

The Impact of Comorbidity and Age on Timing of Androgen Deprivation Therapy in Men with Biochemical Recurrence after Radical Prostatectomy

INTRODUCTION

Older men with major comorbidities have higher risks of morbidity and mortality from androgen deprivation therapy, and the benefits of immediate androgen deprivation therapy after biochemical recurrence in these men are unclear. We assessed variation in timing of androgen deprivation therapy by age and comorbidity in a cohort of men with biochemical recurrence after radical prostatectomy.

METHODS

We analyzed 2,097 men with biochemical recurrence after radical prostatectomy from 2000 to 2017 in the VA SEARCH database. We ascertained age and Deyo-Charlson comorbidity index scores at biochemical recurrence. Kaplan-Meier analysis and multivariable logistic regression were used to determine association of age and Deyo-Charlson comorbidity index with prostate specific antigen at the initiation of androgen deprivation therapy.

RESULTS

In Kaplan-Meier analysis with prostate specific antigen at androgen deprivation therapy as the outcome, median prostate specific antigen at androgen deprivation therapy initiation was 6.2 ng/ml (95% CI 5.1-7.1) across all patients but differed among those who received adjuvant/salvage radiation (3.6 ng/ml, 95% CI 2.8-4.3) and those who did not (12.1 ng/ml, 95% CI 9.6-15.2, p <0.001). In multivariable Cox regression, advanced age (p=0.03) but not worse comorbidity (p=0.25) was associated higher prostate specific antigen at initiation of androgen deprivation therapy. Across all patients, prostate specific antigen at androgen deprivation therapy was lower among those <60 years old (3.7 ng/ml, 95% CI 2.6-5.8) compared to those 60-64 (5.0 ng/ml, 95% CI 3.9-6.6), 65-69 (6.6 ng/ml, 95% CI 4.9-8.8), 70-74 (8.8 ng/ml, 95% CI 6.1-12.3) and ≥75 years old (14.1 ng/ml, 95% CI 5.5-37.8). In contrast, prostate specific antigen at androgen deprivation therapy was similar among comorbidity subgroups (Deyo-Charlson comorbidity index 0: 6.3 ng/ml, 95% CI 5.0-7.9 vs Deyo-Charlson comorbidity index 3 or higher: 5.6 ng/ml, 95% CI 4.1-7.4). In general, these relationships were consistent among subgroups receiving adjuvant/salvage radiation.

CONCLUSIONS

Men with comorbid disease at increased risk of morbidity and mortality with androgen deprivation therapy often receive androgen deprivation therapy at low prostate specific antigen values.

Development and Validation of a Clinical Prognostic Stage Group System for Nonmetastatic Prostate Cancer Using Disease-Specific Mortality Results From the International Staging Collaboration for Cancer of the Prostate

Importance

In 2016, the American Joint Committee on Cancer (AJCC) established criteria to evaluate prediction models for staging. No localized prostate cancer models were endorsed by the Precision Medicine Core committee, and 8th edition staging was based on expert consensus.

Objective

To develop and validate a pretreatment clinical prognostic stage group system for nonmetastatic prostate cancer.

Design, Setting, and Participants

This multinational cohort study included 7 centers from the United States, Canada, and Europe, the Shared Equal Access Regional Cancer Hospital (SEARCH) Veterans Affairs Medical Centers collaborative (5 centers), and the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) registry (43 centers) (the STAR-CAP cohort). Patients with cT1-4N0-1M0 prostate adenocarcinoma treated from January 1, 1992, to December 31, 2013 (follow-up completed December 31, 2017). The STAR-CAP cohort was randomly divided into training and validation data sets; statisticians were blinded to the validation data until the model was locked. A Surveillance, Epidemiology, and End Results (SEER) cohort was used as a second validation set. Analysis was performed from January 1, 2018, to November 30, 2019.

Exposures

Curative intent radical prostatectomy (RP) or radiotherapy with or without androgen deprivation therapy.

Main Outcomes and Measures

Prostate cancer-specific mortality (PCSM). Based on a competing-risk regression model, a points-based Score staging system was developed. Model discrimination (C index), calibration, and overall performance were assessed in the validation cohorts.

Results

Of 19 684 patients included in the analysis (median age, 64.0 [interquartile range (IQR), 59.0-70.0] years), 12 421 were treated with RP and 7263 with radiotherapy. Median follow-up was 71.8 (IQR, 34.3-124.3) months; 4078 (20.7%) were followed up for at least 10 years. Age, T category, N category, Gleason grade, pretreatment serum prostate-specific antigen level, and the percentage of positive core biopsy results among biopsies performed were included as variables. In the validation set, predicted 10-year PCSM for the 9 Score groups ranged from 0.3% to 40.0%. The 10-year C index (0.796; 95% CI, 0.760-0.828) exceeded that of the AJCC 8th edition (0.757; 95% CI, 0.719-0.792), which was improved across age, race, and treatment modality and within the SEER validation cohort. The Score system performed similarly to individualized random survival forest and interaction models and outperformed National Comprehensive Cancer Network (NCCN) and Cancer of the Prostate Risk Assessment (CAPRA) risk grouping 3- and 4-tier classification systems (10-year C index for NCCN 3-tier, 0.729; for NCCN 4-tier, 0.746; for Score, 0.794) as well as CAPRA (10-year C index for CAPRA, 0.760; for Score, 0.782).

Conclusions and Relevance

Using a large, diverse international cohort treated with standard curative treatment options, a proposed AJCC-compliant clinical prognostic stage group system for prostate cancer has been developed. This system may allow consistency of reporting and interpretation of results and clinical trial design.

Monocyte counts and prostate cancer outcomes in white and black men: results from the SEARCH database

PURPOSE

Circulating inflammatory markers may predict prostate cancer (PC) outcomes. For example, a recent study showed that higher peripheral blood monocyte counts were associated with aggressive PC in Asian men undergoing radical prostatectomy (RP). Herein, we investigated whether peripheral monocyte count can predict long-term PC outcomes after RP in black and white men.

METHODS

We retrospectively reviewed data on 2345 men undergoing RP from 2000 to 2017 at eight Veterans Affairs hospitals. Data on monocyte count within 6 and 12 months prior to surgery were collected. The study outcomes were biochemical recurrence (BCR), castration-resistant PC (CRPC), metastasis, all-cause mortality (ACM), and PC-specific morality (PCSM). Cox-proportional hazard models were used to assess the associations between pre-operative monocyte count and the above-mentioned outcomes accounting for confounders.

RESULTS

Of 2345 RP patients, 972 (41%) were black and 1373 (59%) were white men. In multivariable analyses, we found no associations between monocyte count and BCR among all men (HR: 1.36, 95%CI 0.90-2.07) or when analyses were stratified by race (HR: 1.30, 95%CI 0.69-2.46, in black men; HR:1.33, 95%CI 0.76-02.33, in white men). Likewise, no overall or race-specific associations were found between monocyte count and CRPC, metastases, ACM, and PCSM, all p ≥ 0.15. Results were similar for monocyte count measured at 12 months prior to RP.

CONCLUSION

In black and white PC patients undergoing RP, peripheral monocyte count was not associated with long-term PC outcomes. Contrary to what was found in Asian populations, monocyte count was not associated with PC outcomes in this study.

Do Hispanic Men Have Worse Outcomes After Radical Prostatectomy? Results From SEARCH

OBJECTIVE

To examine the associations between ethnicity and outcomes after radical prostatectomy (RP) among Hispanics. While non-Hispanic Black men have worse prostate cancer (PC) outcomes, there are limited data on outcomes of Hispanic men, especially after RP.

METHODS

We identified 3789 White men who underwent RP between 1988 and 2017 in the Shared Equal Access Regional Cancer Hospital database. Men were categorized as Hispanic or non-Hispanic. Logistic regression was used to test the association between ethnicity and PC adverse features. Cox models were used to test the association between ethnicity and biochemical recurrence (BCR), metastases, and castration-resistant PC (CRPC). All models were adjusted for age, prostate-specific antigen, clinical stage, biopsy grade group, surgery year, and surgical center.

RESULTS

Of 3789 White men, 236 (6%) were Hispanic. Hispanic men had higher prostate-specific antigen, but all other characteristics were similar between ethnicities. On multivariable analysis, there was no difference between ethnicities in odds of extracapsular extension, seminal vesicle invasion, positive margins, positive lymph nodes, or high-grade disease (odds ratio 0.62-0.89, all P > .07). A total of 1168 men had BCR, 182 developed metastasis, and 132 developed CRPC. There was no significant association between Hispanic ethnicity and risk of BCR, metastases, or CRPC (hazards ratio 0.39-0.85, all P > .06).

CONCLUSION

In an equal access setting, we found no evidence Hispanic White men undergoing RP had worse outcomes than non-Hispanic White men. In fact, all hazard ratios were <1 and although they did not achieve statistical significance, suggest perhaps slightly better outcomes for Hispanic men. Larger studies are needed to confirm findings.

Obese men undergoing radical prostatectomy: Is robotic or retropubic better to limit positive surgical margins? Results from SEARCH

OBJECTIVES

To evaluate the association between obesity and positive surgical margins in patients undergoing retropubic radical prostatectomy versus robotic-assisted laparoscopic prostatectomy.

METHODS

We retrospectively reviewed the data of 3141 men undergoing retropubic radical prostatectomy and 1625 undergoing robotic-assisted laparoscopic prostatectomy between 1988 and 2017 at eight Veterans Health Administration hospitals. The positive surgical margin location (peripheral, apical, bladder neck, overall) was determined from pathology reports. We adjusted for age, race, prostate-specific antigen, surgery year, prostate weight, pathological grade group, extracapsular extension, seminal vesicle invasion, hospital surgical volume and surgical method (in analyses not stratified by surgical method). Interactions between body mass index and surgical approach were tested.

RESULTS

Among all patients, higher body mass index was associated with increased odds of overall, peripheral and apical positive surgical margins (OR 1.02-1.03, P ≤ 0.02). Although not statistically significant, there was a trend between higher body mass index and increased odds of bladder neck positive surgical margins (OR 1.03, P = 0.09). Interactions between body mass index and surgical method were significant for peripheral positive surgical margins only (P = 0.024). Specifically, there was an association between body mass index and peripheral positive surgical margins among men undergoing retropubic radical prostatectomy (OR 1.04, P < 0.001), but not robotic-assisted laparoscopic prostatectomy (OR 1.00, P = 0.98). Limitations include lacking individual surgeon data and lacking central pathology review.

CONCLUSIONS

In this multicenter cohort, higher body mass index was associated with increased odds of positive surgical margins at all locations except the bladder neck. Furthermore, there was a significant association between obesity and peripheral positive surgical margins in men undergoing retropubic radical prostatectomy, but not robotic-assisted laparoscopic prostatectomy. Long-term clinical significance requires further study.

Obesity, race, and long-term prostate cancer outcomes

BACKGROUND

The authors previously found that obesity was linked with prostate cancer (PC)-specific mortality (PCSM) among men who underwent radical prostatectomy (RP). Herein, in a larger RP cohort, the authors investigated whether the association between obesity and long-term PC outcomes, including PCSM, differed by race.

METHODS

Data from 5929 patients who underwent RP and were in the Shared Equal Access Regional Cancer Hospital (SEARCH) database were analyzed. Prior to RP, body mass index (BMI) was measured and recorded in the medical records. BMI was categorized as normal weight (<25 kg/m² ), overweight (25-29.9 kg/m² ), and obese (≥30 kg/m² ). The authors assessed the association between BMI and biochemical disease recurrence (BCR), castration-resistant prostate cancer (CRPC), metastasis, and PCSM, accounting for confounders.

RESULTS

Of the 5929 patients, 1983 (33%) were black, 1321 (22%) were of normal weight, 2605 (44%) were overweight, and 2003 (34%) were obese. Compared with white men, black men were younger; had higher prostate-specific antigen levels; and were more likely to have a BMI ≥30 kg/m² , seminal vesicle invasion, and positive surgical margins (all P ≤ .032). During a median follow-up of 7.4 years, a total of 1891 patients (32%) developed BCR, 181 patients (3%) developed CRPC, 259 patients (4%) had metastasis, and 135 patients (2%) had died of PC. On multivariable analysis, obesity was found to be associated with an increased risk of PCSM (hazard ratio, 1.78; 95% confidence interval, 1.04-3.04 [P = .035]). No interaction was found between BMI and race in predicting PCSM (P ≥ .88), BCR (P ≥ .81), CRPC (P ≥ .88), or metastasis (P ≥ .60). Neither overweight nor obesity was associated with risk of BCR, CRPC, or metastasis (all P ≥ .18).

CONCLUSIONS

Obese men undergoing RP at several Veterans Affairs hospitals were found to be at an increased risk of PCSM, regardless of race.

Race does not predict skeletal-related events and all-cause mortality in men with castration-resistant prostate cancer

BACKGROUND

The impact of race on prostate cancer skeletal-related events (SREs) remains understudied. In the current study, the authors tested the impact of race on time to SREs and overall survival in men with newly diagnosed, bone metastatic castration-resistant prostate cancer (mCRPC).

METHODS

The authors performed a retrospective study of patients from 8 Veterans Affairs hospitals who were newly diagnosed with bone mCRPC in the year 2000 or later. SREs comprised pathologic fracture, spinal cord compression, radiotherapy to the bone, or surgery to the bone. Time from diagnosis of bone mCRPC to SREs and overall mortality was estimated using the Kaplan-Meier method. Cox models tested the association between race and SREs and overall mortality.

RESULTS

Of 837 patients with bone mCRPC, 232 patients (28%) were black and 605 (72%) were nonblack. At the time of diagnosis of bone mCRPC, black men were found to be more likely to have more bone metastases compared with nonblack men (29% vs 19% with ≥10 bone metastases; P = .021) and to have higher prostate-specific antigen (41.7 ng/mL vs 29.2 ng/mL; P = .005) and a longer time from the diagnosis of CRPC to metastasis (17.9 months vs 14.3 months; P < .01). On multivariable analysis, there were no differences noted with regard to SRE risk (hazard ratio [HR], 0.80; 95% CI, 0.59-1.07) or overall mortality (HR, 0.87; 95% CI, 0.73-1.04) between black and nonblack people, although the HRs were <1, which suggested the possibility of better outcomes.

CONCLUSIONS

No significant association between black race and risk of SREs and overall mortality was observed in the current study. These data have suggested that efforts to understand the basis for the excess risk of aggressive prostate cancer in black men should focus on cancer development and progression in individuals with early-stage disease.

Survival outcomes and practice trends for off-label use of adjuvant targeted therapy in high-risk locoregional renal cell carcinoma

IMPORTANCE

The appropriate use of adjuvant targeted therapy (TT) for high-risk locoregional renal cell carcinoma (RCC) after nephrectomy is currently unclear due to mixed results from the relevant randomized controlled trials. National-level survival outcomes and practice trends for the use of adjuvant TT in the United States have not been reported.

OBJECTIVE

To compare overall survival for patients who did and did not receive adjuvant TT after nephrectomy for high-risk locoregional RCC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study reviewed the National Cancer Database from 2006 to 2015. Patients with nonmetastatic clear cell RCC who underwent nephrectomy with either stage pT3a or greater or pN+ were included.

MAIN OUTCOMES AND MEASURES

Adjuvant TT was defined as receipt of TT within 3 months of nephrectomy. The primary end point was overall survival from initial diagnosis to date of death or censored at last follow-up. Baseline characteristics were described, and a multivariable analysis identified associations for receipt of adjuvant TT. Nearest-neighbor propensity matching was performed to create similar groups for comparison. A survival analysis was performed using Kaplan-Meier analysis and log-rank test.

RESULTS

The final study population included 41,127 patients. Two thousand seventy-one patients (5.04%) received off-label adjuvant TT. Younger age, white race, private insurance, positive margins, pT4, and pN+ were associated with receipt of adjuvant TT. After nearest-neighbor propensity matching for clinically and statistically relevant covariates, 1,604 patients remained in the matched cohort, with statistically nonsignificant differences between the groups for all baseline characteristics. Median overall survival was 52 months for patients in the Adjuvant TT group versus 79 months for those who did not receive adjuvant TT (P < 0.001). Decreased overall survival for patients receiving adjuvant therapy was also seen in pathologic subgroups with and without lymph node involvement.

CONCLUSIONS

The propensity matched survival analysis revealed significantly decreased overall survival in patients who received off-label adjuvant TT for high-risk locoregional RCC.

Influence of African American race on the association between preoperative biopsy grade group and adverse histopathologic features of radical prostatectomy

BACKGROUND

The current study was performed to evaluate the influence of race on the association between biopsy grade group (GrGp) and the risk of detectable prostate-specific antigen (PSA) and adverse histopathological outcomes after radical prostatectomy (RP).

METHODS

Data regarding 4073 men (1344 African American men; 33%) who were treated with RP were categorized based on the 5-tiered GrGp system. Logistic regression was used to test the association between biopsy GrGp and PSA nadir (<0.1 ng/mL) after RP as well as adverse pathological features among all patients and stratified by race.

RESULTS

Those patients with a higher biopsy GrGp were found to have lower odds of achieving a PSA nadir <0.1 ng/mL after RP on unadjusted and multivariable analysis (both P < .001). On unadjusted and multivariable analysis, higher GrGp was associated with increased odds of each of the adverse pathological features, namely, GrGp ≥3, extraprostatic extension, seminal vesicle invasion, positive surgical resection margin, and positive lymph nodes (all P < .001). Race had no significant interaction with biopsy GrGp in the prediction of PSA nadir after RP (P = .91) or any adverse pathological features (all P > .06) except positive lymph nodes. When the models were stratified by race, the associations between preoperative biopsy GrGp and having a PSA nadir <0.1 ng/mL, high-grade final pathology, or other adverse histopathologic features were similar in both races except as noted for positive lymph nodes.

CONCLUSIONS

Higher preoperative biopsy GrGp is associated with increased odds of adverse histopathological findings as well as lower odds of a PSA nadir <0.1 ng/mL after RP. These associations are largely independent of race, suggesting that GrGp is an accurate tool for risk stratification in both black and white men.

Predictors of skeletal-related events and mortality in men with metastatic, castration-resistant prostate cancer: Results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database

BACKGROUND

Although skeletal-related events (SREs) are linked with a reduced quality of life and worse outcomes, to the authors' knowledge the factors that predict SREs are minimally understood. The objective of the current study was to identify predictors of SREs and all-cause mortality among men with metastatic castration-resistant prostate cancer (mCRPC).

METHODS

Data were collected on 837 men with bone mCRPC at 8 Veterans Affairs medical centers within the Shared Equal Access Regional Cancer Hospital (SEARCH) database from 2000 through 2017. Patients were followed to assess development of SREs (pathological fracture, radiotherapy to bone, spinal cord compression, or surgery to bone). Cox proportional hazards models were used to evaluate predictors of SREs and mortality.

RESULTS

Of the 837 men with bone mCRPC, 287 developed a SRE and 740 men died (median follow-up, 26 months). Bone pain was found to be the strongest predictor of SREs (hazard ratio [HR], 2.96; 95% CI, 2.25-3.89). A shorter time from CRPC to the development of metastasis (HR, 0.92; 95% CI, 0.85-0.99), shorter progression to CRPC (HR, 0.94; 95% CI, 0.91-0.98), and visceral metastasis at the time of diagnosis of bone metastasis (HR, 1.91; 95% CI, 1.18-3.09) were associated with an increased risk of SREs. Ten or more bone metastases (HR, 2.17; 95% CI, 1.72-2.74), undergoing radical prostatectomy (HR, 0.73; 95% CI, 0.61-0.89), shorter progression to CRPC (HR, 0.97; 95% CI, 0.94-0.99), older age (HR, 1.03; 95% CI, 1.02-1.04), higher prostate-specific antigen level at the time of diagnosis of metastasis (HR, 1.21; 95% CI, 1.14-1.28), bone pain (HR, 1.44; 95% CI, 1.23-1.70), and visceral metastasis (HR, 1.72; 95% CI, 1.23-2.39) were associated with an increased mortality risk.

CONCLUSIONS

Among men with bone mCRPC, bone pain was found to be the strongest predictor of SREs and the number of bone metastases was a strong predictor of mortality. If validated, these factors potentially may be used for risk stratification and for SRE prevention strategies.

Association of Black Race With Prostate Cancer-Specific and Other-Cause Mortality

Importance

Black men are more likely to die of prostate cancer than white men. In men with similar stages of disease, the contribution of biological vs nonbiological differences to this observed disparity is unclear.

Objective

To quantify the association of black race with long-term survival outcomes after controlling for known prognostic variables and access to care among men with prostate cancer.

Design, Setting, and Participants

This multiple-cohort study included updated individual patient-level data of men with clinical T1-4N0-1M0 prostate cancer from the following 3 cohorts: Surveillance, Epidemiology, and End Results (SEER [n = 296 273]); 5 equal-access regional medical centers within the Veterans Affairs health system (VA [n = 3972]); and 4 pooled National Cancer Institute-sponsored Radiation Therapy Oncology Group phase 3 randomized clinical trials (RCTs [n = 5854]). Data were collected in the 3 cohorts from January 1, 1992, through December 31, 2013, and analyzed from April 27, 2017, through April 13, 2019.

Exposures

In the VA and RCT cohorts, all patients received surgery and radiotherapy, respectively, with curative intent. In SEER, radical treatment, hormone therapy, or conservative management were received.

Main Outcomes and Measures

Prostate cancer-specific mortality (PCSM). Secondary measures included other-cause mortality (OCM). To adjust for demographic-, cancer-, and treatment-related baseline differences, inverse probability weighting (IPW) was performed.

Results

Among the 306 100 participants included in the analysis (mean [SD] age, 64.9 [8.9] years), black men constituted 52 840 patients (17.8%) in the SEER cohort, 1513 (38.1%) in the VA cohort, and 1129 (19.3%) in the RCT cohort. Black race was associated with an increased age-adjusted PCSM hazard (subdistribution hazard ratio [sHR], 1.30; 95% CI, 1.23-1.37; P < .001) within the SEER cohort. After IPW adjustment, black race was associated with a 0.5% (95% CI, 0.2%-0.9%) increase in PCSM at 10 years after diagnosis (sHR, 1.09; 95% CI, 1.04-1.15; P < .001), with no significant difference for high-risk men (sHR, 1.04; 95% CI, 0.97-1.12; P = .29). No significant differences in PCSM were found in the VA IPW cohort (sHR, 0.85; 95% CI, 0.56-1.30; P = .46), and black men had a significantly lower hazard in the RCT IPW cohort (sHR, 0.81; 95% CI, 0.66-0.99; P = .04). Black men had a significantly increased hazard of OCM in the SEER (sHR, 1.30; 95% CI, 1.27-1.34; P < .001) and RCT (sHR, 1.17; 95% CI, 1.06-1.29; P = .002) IPW cohorts.

Conclusions and Relevance

In this study, after adjustment for nonbiological differences, notably access to care and standardized treatment, black race did not appear to be associated with inferior stage-for-stage PCSM. A large disparity remained in OCM for black men with nonmetastatic prostate cancer.

Validity of the National Death Index to ascertain the date and cause of death in men having undergone prostatectomy for prostate cancer

Background

The National Death Index (NDI) is a centralized database containing information from death certificates that is frequently referenced by health and medical investigators to ascertain vital statistics. Yet, it commonly includes misclassified causes of death. Since the NDI is frequently relied upon in studies that evaluate outcomes following radical prostatectomy (RP) for prostate cancer (PC), we evaluated its validity by referencing mortality data from the Shared Equal Access Regional Cancer Hospital (SEARCH) database which is a prospectively managed database of 5,009 Veterans who underwent a RP at eight Veterans Affairs medical centers between 1982 and 2016.

Methods

We compared vital status, cause of death and date of death from the SEARCH database with the NDI.

Results

A total of 1,312 men in SEARCH were deceased, yet the NDI reported 17% (219) of those men as still alive. Among the 1,093 men who had concordant vital status in both SEARCH and NDI, the date of death was an exact match within one day, a week, or 31 days in 94%, 97%, 99%, and 100%, respectively. Of those men coded as dying from prostate cancer in the SEARCH database (n=105), 12% were coded as having died from non-PC causes in the NDI. Meanwhile, among patients coded by the NDI as having died of PC (n=139), 34% were coded in SEARCH as having died of non-PC causes.

Conclusions

These findings demonstrate that the NDI provides accurate dates of death, but frequently misclassifies whether a death was due to prostate cancer. Studies that rely upon death certificates, as capture in the NDI, may be unreliable to report prostate cancer specific mortality rates after prostatectomy.

Poorly controlled diabetes increases the risk of metastases and castration-resistant prostate cancer in men undergoing radical prostatectomy: Results from the SEARCH database

BACKGROUND

Although diabetes is inversely related to prostate cancer (PC) risk, to the authors' knowledge the impact of glycemic control on PC progression is unknown. In the current study, the authors tested the association between hemoglobin A1c (HbA1c) and long-term PC outcomes among diabetic men undergoing radical prostatectomy (RP).

METHODS

The authors retrospectively reviewed data regarding men undergoing RP from 2000 to 2017 at 8 Veterans Affairs hospitals. Diabetic patients were identified using International Classification of Diseases, Ninth Revision (ICD-9) codes (250.x) or by an HbA1c value >6.5% at any time before RP. Cox models tested the association between HbA1c and biochemical disease recurrence (BCR), castration-resistant PC (CRPC), metastases, PC-specific mortality, and all-cause mortality. The model for BCR was adjusted for multiple variables. Due to limited events, models for long-term outcomes were adjusted for biopsy grade and prostate-specific antigen only.

RESULTS

A total of 1409 men comprised the study population. Of these, 699 patients (50%) had an HbA1c value <6.5%, 631 (45%) had an HbA1c value of 6.5% to 7.9%, and 79 (6%) had an HbA1c value ≥8.0%. Men with an HbA1c value ≥8.0% were younger (P < .001) and more likely to be black (P = .013). The median follow-up after RP was 6.8 years (interquartile range, 3.7-10.6 years). On multivariable analysis, HbA1c was not found to be associated with BCR. However, a higher HbA1c value was associated with metastasis (hazard ratio [HR], 1.21; 95% CI, 1.02-1.44 [P = .031]) and CRPC (HR, 1.27; 95% CI, 1.03-1.56 [P = .023]). Although not statistically significant, there were trends between higher HbA1c and risk of PC-specific mortality (HR, 1.24; 95% CI, 0.99-1.56 [P = .067]) and all-cause mortality (HR, 1.09; 95% CI, 0.99-1.19 [P = .058]).

CONCLUSIONS

Among diabetic men undergoing RP, a higher HbA1c value was associated with metastases and CRPC. If validated in larger studies with longer follow-up, future research should test whether better glycemic control improves long-term PC outcomes.

Racial disparities in radium-223 treatment in a large real-world population

268

Background: Black men with prostate cancer are more likely to have unfavorable tumor characteristics and are at greater risk of prostate cancer mortality. Radium-223 is a FDA approved treatment for metastatic castration-resistant prostate cancer (mCRPC) that showed a survival benefit in the ALSYMPCA trial, where 94% of the participants were Caucasian. We aim to examine treatment patterns and outcomes of radium-223 in a large, heterogeneous population in the real world. Methods: We reviewed charts of all men with diagnosed with mCRPC in the entire Veterans Affairs (VA) system alive as of January 1st, 2013 who received radium-223. We compared common treatment patterns and characteristics between black and nonblack men. We analyzed predictors of time from radium-223 start to overall survival and time to skeletal related event (SRE) with Cox models. Results: 318 patients with bone mCRPC who received radium-223 were identified. 27% (87/318) were black. Black men were younger (67 vs 70 years, p = 0.001) and had higher PSA and alkaline phosphatase (ALP) levels at radium start (p = 0.014 and 0.017, respectively). There were no significant differences in biopsy Gleason, number of bone metastasis, primary localized treatment (yes/no), PSA doubling time, bone pain, or number of radium injections. Black men had lower mortality risk (HR 0.75; 95% CI 0.57 to 0.98; P = 0.038) on multivariable analysis. Comparison of common treatment patterns between black and nonblack men revealed that black men were more likely to receive other therapies prior to radium, including chemotherapy. Conclusions: Using a large, heterogeneous, real world cohort, we describe differences in treatment patterns and outcomes with radium-223 between black and nonblack men with mCRPC. While black men had a lower risk of mortality in this cohort, they had higher PSA and ALP levels when receiving radium-223. They were also more likely to receive other therapies prior to radium-223, indicating a possible delay in radium use in black men.

First-year weight loss with androgen-deprivation therapy increases risks of prostate cancer progression and prostate cancer-specific mortality: results from SEARCH

PURPOSE

We aimed to study the associations between androgen-deprivation therapy (ADT)-induced weight changes and prostate cancer (PC) progression and mortality in men who had undergone radical prostatectomy (RP).

METHODS

Data from the Shared Equal Access Regional Cancer Hospital (SEARCH) cohort were used to study the associations between weight change approximately 1-year post-ADT initiation and metastases, castration-resistant prostate cancer (CRPC), all-cause mortality (ACM), and PC-specific mortality (PCSM) in 357 patients who had undergone RP between 1988 and 2014. We estimated hazard ratios (HR) and 95% confidence intervals (95% CI) using covariate-adjusted Cox regression models for associations between weight loss, and weight gains of 2.3 kg or more, and PC progression and mortality post-ADT.

RESULTS

During a median (IQR) follow-up of 81 (46-119) months, 55 men were diagnosed with metastases, 61 with CRPC, 36 died of PC, and 122 died of any cause. In multivariable analysis, weight loss was associated with increases in risks of metastases (HR 3.13; 95% CI 1.40-6.97), PCSM (HR 4.73; 95% CI 1.59-14.0), and ACM (HR 2.16; 95% CI 1.25-3.74) compared with mild weight gains of ≤ 2.2. Results were slightly attenuated but remained statistically significant in analyses that accounted for competing risks of non-PC death. Estimates for the associations between weight gains of ≥ 2.3 kg and metastases (HR 1.58; 95% CI 0.73-3.42), CRPC (HR 1.33; 95% CI 0.66-2.66), and PCSM (HR 2.44; 95% CI 0.84-7.11) were elevated, but not statistically significant.

CONCLUSIONS

Our results suggest that weight loss following ADT initiation in men who have undergone RP is a poor prognostic sign. If confirmed in future studies, testing ways to mitigate weight loss post-ADT may be warranted.

Radium-223 treatment patterns in a large real-world population

190

Background: For men with symptomatic metastatic castration resistant prostate cancer (mCRPC), radium-223 was shown to improve overall survival in the phase III, double blind ALSYMPCA trial. Despite the observed benefits, the application and practice patterns of Radium-223 outside of clinical trials are largely unknown. Here we aim to better characterize the use of radium-223 in a large and heterogeneous real-world population. We identify treatment patterns associated with radium-223 and link these patterns with time to skeletal related event (SRE) and mortality. Methods: We reviewed charts of all men with diagnosed with mCRPC in the entire Veterans Affairs (VA) system alive as of January 1, 2013 who received radiun-223. We generated Kaplan Meier curves for survival and time to SRE based on treatment patterns. We examined the association between common treatment patterns and mortality and time to SRE with Cox models. Results: We identified 318 men with bone mCRPC who received radium-223. Median age at radium start was 69 ys and median follow up was 25.3 months. Median survival was 11 months. 277 patients died during the study period (87%). 50% (158/318) completed ≤4 injections. There was a significant difference mortality among four consolidated treatment patterns (p=0.005) and but no difference SRE (p=0.10). On univariable and multivariable analysis, men who received AR target + docetaxel + radium-223 had increased mortality vs. men who received AR target + radium-223 (p=0.010 and 0.005, respectively). Multivariable analysis showed that non-black race, bone pain, SRE prior to radium, and higher PSA were all linked with worse mortality. Conclusions: We described the largest known cohort of men in the real world who received radium-223. We identified common treatment patterns with differing risk for overall mortality. Further prospective studies are needed to better understand whether differences in survival are attributed to worsening disease status requiring more aggressive therapy, lead-time bias, or true differences in treatment efficacy.

Practice patterns and outcomes of equivocal bone scans for patients with castration-resistant prostate cancer: Results from SEARCH

Objective

To review follow-up imaging after equivocal bone scans in men with castration resistant prostate cancer (CRPC) and examine the characteristics of equivocal bone scans that are associated with positive follow-up imaging.

Methods

We identified 639 men from five Veterans Affairs Hospitals with a technetium-99m bone scan after CRPC diagnosis, of whom 99 (15%) had equivocal scans. Men with equivocal scans were segregated into “high-risk” and “low-risk” subcategories based upon wording in the bone scan report. All follow-up imaging (bone scans, computed tomography [CT], magnetic resonance imaging [MRI], and X-rays) in the 3 months after the equivocal scan were reviewed. Variables were compared between patients with a positive vs. negative follow-up imaging after an equivocal bone scan.

Results

Of 99 men with an equivocal bone scan, 43 (43%) received at least one follow-up imaging test, including 32/82 (39%) with low-risk scans and 11/17 (65%) with high-risk scans (p = 0.052). Of follow-up tests, 67% were negative, 14% were equivocal, and 19% were positive. Among those who underwent follow-up imaging, 3/32 (9%) low-risk men had metastases vs. 5/11 (45%) high-risk men (p = 0.015).

Conclusion

While 19% of all men who received follow-up imaging had positive follow-up imaging, only 9% of those with a low-risk equivocal bone scan had metastases versus 45% of those with high-risk. These preliminary findings, if confirmed in larger studies, suggest follow-up imaging tests for low-risk equivocal scans can be delayed while high-risk equivocal scans should receive follow-up imaging.

Socioeconomic status, race, and long-term outcomes after radical prostatectomy in an equal access health system: Results from the SEARCH database

INTRODUCTION

We previously found racial differences in biochemical recurrence (BCR) after radical prostatectomy (RP) persisted after adjusting for socioeconomic status (SES) while SES did not predict BCR. The impact on long-term prostate cancer (PC) outcomes is unclear. We hypothesized higher SES would associate with better long-term outcomes regardless of race.

METHODS

Among 4,787 black and white men undergoing RP from 1988 to 2015 in the SEARCH Database, poverty (primary SES measure) was estimated by linking home ZIP-code to census data. Cox models were used to test the association between SES adjusting for demographic, clinicopathological features, and race with BCR, castration-resistant PC (CRPC), metastases, PC-specific mortality (PCSM), and all-cause mortality. Interactions between race and SES were tested.

RESULTS

Median follow-up was 98 months (Interquartile range: 54-150 months). There were no interactions between race and SES for BCR. Black men had 10%- to 11% increased BCR risk (P < 0.06) while SES was unrelated to BCR. There were interactions between SES and race for CRPC (P = 0.002), metastasis (P = 0.014), and PCSM (P = 0.004). Lower SES was associated with decreased CRPC (P = 0.012), metastases (P = 0.004), and PCSM (P = 0.049) in black, but not white men (all P ≥ 0.22). Higher SES was associated with decreased all-cause mortality in both races.

CONCLUSIONS

In an equal-access setting, lower SES associated with decreased CRPC, metastases, and PCSM in black but not white men. If confirmed, these findings suggest a complex relationship between race, SES, and PC with further research needed to understand why low SES in black men decreased the risk for poor PC outcomes after RP.

Obesity, risk of biochemical recurrence, and prostate-specific antigen doubling time after radical prostatectomy: results from the SEARCH database

OBJECTIVES

To examine the association between body mass index (BMI) and aggressive biochemical recurrence (BCR) using the Shared Equal Access Regional Cancer Hospital (SEARCH) database.

MATERIAL AND METHODS

We identified 4123 men with complete data treated by radical prostatectomy between 1988 and 2015. We tested the association between BMI and BCR using Cox models, and among men with BCR, prostate-specific antigen doubling time (PSADT) was compared across BMI categories using linear regression. Models were adjusted for age, race, prostate-specific antigen, biopsy Gleason score, clinical stage, year and surgical centre.

RESULTS

Overall, 922 men (22%) were of normal weight (BMI <25 kg/m² ), 1863 (45%) were overweight (BMI 25-29.9 kg/m² ), 968 (24%) were obese (BMI 30-34.9 kg/m² ), and 370 (9%) were moderately or severely obese (BMI ≥35 kg/m² ). After adjustment for multiple clinical characteristics, higher BMI was significantly associated with higher risk of BCR (P = 0.008). Among men with BCR, men in the four BMI categories had similar multivariable-adjusted PSADT values (increasing BMI categories: 20.9 vs 21.3 vs 21.0 vs 14.9 months; P = 0.48).

CONCLUSION

While we confirmed that higher BMI was associated with BCR, we found no link between BMI and PSADT at the time of recurrence. Our data suggest obese men do not have more aggressive recurrences. Future studies are needed to test whether obesity predicts response to salvage therapies.

Does race predict the development of metastases in men who receive androgen-deprivation therapy for a biochemical recurrence after radical prostatectomy?

BACKGROUND

In this study among men who underwent radical prostatectomy (RP), African American men (AAM) were 28% more likely to develop recurrent disease compared with Caucasian men (CM). However, among those who had nonmetastatic, castration-resistant prostate cancer (CRPC), race did not predict metastases or overall survival. Whether race predicts metastases among men who receive androgen-deprivation therapy (ADT) after a biochemical recurrence (BCR) (ie, before CRPC but after BCR) is untested.

METHODS

The authors identified 595 AAM and CM who received ADT for a BCR that developed after RP between 1988 and 2015 in the Shared Equal-Access Regional Cancer Hospital (SEARCH) database. Univariable and multivariable Cox models were used to test the association between race and the time from ADT to metastases. Secondary outcomes included the time to CRPC, all-cause mortality, and prostate cancer-specific mortality.

RESULTS

During a median follow-up of 66 months after ADT, 62 of 354 CM (18%) and 38 of 241 AAM (16%) developed metastases. AAM were younger at the time they received ADT (63 vs 67 years; P < .001), had received ADT in a more recent year (2008 vs 2006; P < .001), had higher prostate-specific antigen levels at RP (11.1 vs 9.2 ng/mL; P < .001), lower pathologic Gleason scores (P = .004), and less extracapsular extension (38% vs 48%; P = .022). On multivariable analysis, there was no association between race and metastases (hazard radio, 1.20; P = .45) or any of the other secondary outcomes (all P > .5).

CONCLUSIONS

Among veterans who received ADT post-BCR after RP, race was not a predictor of metastases or other adverse outcomes. The current findings suggest that research efforts to understand racial differences in prostate cancer biology should focus on early stages of the disease (ie, closer to the time of diagnosis).

Impact of age, comorbidity, and PSA doubling time on long-term competing risks for mortality among men with non-metastatic castration-resistant prostate cancer

BACKGROUND

Understanding competing risks for mortality is critical in determining prognosis among men with non-metastatic castration-resistant prostate cancer (nmCRPC), a disease state that often affects older men and has substantial heterogeneity in risk of cancer mortality. We sought to determine the impact of age, comorbidity, and PSA doubling time (PSADT) on competing risks for mortality in men with nmCRPC.

METHODS

We conducted a retrospective analysis of 1238 patients diagnosed with nmCRPC in 2000-2015 in the SEARCH database. Multivariable Cox proportional hazards and competing risks regression were used to determine the hazards of overall, prostate cancer-specific (PCSM), and other-cause mortality (OCM) across age, Charlson comorbidity index (CCI), and PSADT subgroups.

RESULTS

Men with nmCRPC were elderly (median age 77) and had substantial comorbidity burdens (CCI > 1 n = 701, 57%). Multivariable Cox analysis showed higher CCI was associated with higher hazard of OCM, while slower PSADT was associated with lower hazard of PCSM across all age subgroups. Among those with CCI ≥ 3 (vs. CCI0), the hazard ratio of OCM was 2.7 (95% CI 1.1-6.3), 2.0 (95% CI 1.1-3.6), and 2.5 (95% CI 1.5-4.0) for those aged <70, 70-79, and ≥80, respectively. Among those with PSADT ≥ 9 months (vs. < 9 months), the hazard ratios for PCSM were 0.5 (95% CI 0.3-0.9), 0.6 (95% CI 0.4-0.9), and 0.6 (95% CI 0.4-0.9) for those aged <70, 70-79, and ≥80. Competing risks curves revealed PCSM was the predominant cause of death for those with PSADT < 9 months across all age and comorbidity groups. PCSM and OCM were relatively equal competitors for mortality among those with PSADT≥9 months except those aged > 80 with CCI ≥ 3, in whom OCM was the predominant cause of death.

CONCLUSIONS

Among men with nmCRPC, age, comorbidity, and PSADT are associated with risk and cause of death and may assist clinicians in counseling patients regarding cancer prognosis.

Impact of prior local therapy on overall survival in men with metastatic castration-resistant prostate cancer: Results from Shared Equal Access Regional Cancer Hospital

OBJECTIVES

To evaluate the impact of previous local treatment on survival in men with newly diagnosed metastatic castration-resistant prostate cancer.

METHODS

We carried out a retrospective study of patients newly diagnosed with metastatic castration-resistant prostate cancer in the year 2000 or later from eight Veterans Affairs Medical Centers. Patients were categorized based on prior local therapy (none, prostatectomy ± radiation or radiation alone). Overall and cancer-specific survival was estimated by the Kaplan-Meier method. Cox proportional hazards regression models were used to test the association between prior local treatment and survival.

RESULTS

Of 729 patients, 284 (39%) underwent no local treatment, 176 (24%) underwent radical prostatectomy ± radiation and 269 (37%) underwent radiation alone. On multivariable analysis, men with prior prostatectomy had improved overall (hazard ratio 0.71, P = 0.005) and cancer-specific survival (hazard ratio 0.55, P < 0.001) compared with men with no prior local therapy. This improvement in overall (hazard ratio 0.89, P = 0.219) and cancer-specific survival (hazard ratio 0.87, P = 0.170) was not seen in men with prior radiation alone. After further adjusting for comorbidity with the Charlson Comorbidity Index, patients with prior prostatectomy still had improved overall survival (hazard ratio 0.70, P = 0.003), whereas this was not seen in patients who received prior radiation alone (hazard ratio 0.88, P = 0.185).

CONCLUSIONS

Independent of patient- and disease-related factors, men with metastatic castration-resistant prostate cancer who had undergone prior radical prostatectomy have improved overall and cancer-specific survival compared with those with no prior local therapy.

Endorectal MR imaging of prostate cancer: Evaluation of tumor capsular contact length as a sign of extracapsular extension

OBJECTIVE

To evaluate the length of contact between dominant tumor foci and the prostatic capsule as a sign of extracapsular extension at endorectal multiparametric MR imaging.

MATERIALS AND METHODS

We retrospectively identified 101 patients over a three-year interval who underwent endorectal multiparametric prostate MR imaging prior to radical prostatectomy for prostate cancer. Two readers identified the presence of dominant tumor focus (largest lesion with PI-RADS version 2 score of 4 or 5), and measured the length of tumor capsular contact and likelihood of extracapsular extension by standard criteria (1-5 Likert scale). Results were analyzed using histopathological review as reference standard.

RESULTS

Extracapsular extension was found at histopathological review in 27 patients. Reader 1 (2) identified dominant tumor in 79 (73) patients, with mean tumor capsular contact length of 18.2 (14.0) mm. The area under the receiver operating characteristic curve for identification of extracapsular extension by tumor capsular contact length was 0.76 for reader 1 and 0.77 for reader 2, with optimal discrimination at values of 18 mm and 21 mm, respectively. In the subset of patients without obvious extracapsular extension by standard criteria (Likert scores 1-3), corresponding values were 0.74 and 0.66 with optimal thresholds of 24 and 21 mm.

CONCLUSION

Length of contact between the dominant tumor focus and the capsule is a moderately useful sign of extracapsular extension at endorectal multiparametric prostate MR imaging, including the subset of patients without obvious extracapsular extension by standard criteria, with optimal discrimination at threshold values of 18 to 24 mm.

Obese patients with castration-resistant prostate cancer may be at a lower risk of all-cause mortality: results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database

OBJECTIVE

To assess whether obesity is associated with progression to metastasis, prostate cancer-specific mortality (PCSM), and all-cause mortality (ACM), in patients with non-metastatic castration-resistant prostate cancer (non-mCRPC). At the population level, obesity is associated with prostate cancer mortality; however, some studies have found that higher body mass index (BMI) is associated with better long-term prostate cancer outcomes amongst men with mCRPC.

PATIENTS AND METHODS

We identified 1 192 patients with non-mCRPC from the Shared Equal Access Regional Cancer Hospital (SEARCH) database. BMI was calculated from height and weight abstracted from the medical records at the time closest to but prior to CRPC diagnosis and categorised as underweight (<21 kg/m² ), normal weight (21-24.9 kg/m² ), overweight (25-29.9 kg/m² ), and obese (≥30 kg/m² ). Competing risks regression and Cox models were used to test associations between obesity and progression to metastasis, PCSM, and ACM, accounting for confounders.

RESULTS

Overall, 51 (4%) men were underweight, 239 (25%) were normal weight, 464 (39%) were overweight, and 438 (37%) were obese. In adjusted analysis, higher BMI was significantly associated with reduced ACM (hazard ratio [HR] 0.98, P = 0.012) but not PCSM (HR 1.00, P = 0.737) or metastases (HR 0.99, P = 0.225). Likewise, when BMI was treated as a categorical variable in adjusted models, obesity was not associated with PCSM (HR 1.11, P = 0.436) or metastases (HR 1.06, P = 0.647), but was associated with decreased ACM (HR 0.79, P = 0.016) compared to normal weight. No data were available on treatments received after CRPC diagnosis.

CONCLUSIONS

Amongst patients with non-mCRPC obesity was associated with better overall survival. Although this result mirrors evidence from men with mCRPC, obesity was not associated with prostate cancer outcomes. Larger studies are needed to confirm these findings.

Radical prostatectomy and the effect of close surgical margins: results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database

OBJECTIVE

To evaluate biochemical recurrence (BCR) patterns amongst men undergoing radical prostatectomy (RP) with specimens having negative (NSM), positive (PSM), and close surgical margins (CSM) from the Shared Equal Access Regional Cancer Hospital (SEARCH) cohort, as PSM after RP are a significant predictor of biochemical failure and possible disease progression, with CSM representing a diagnostic challenge for surgeons.

PATIENTS AND METHODS

Men undergoing RP between 1988 and 2015 with known final pathological margin status were evaluated. The cohort was divided into three groups based on margin status; NSM, PSM, and CSM. CSM were defined by distance of tumour ≤1 mm from the surgical margin. BCR was defined as a prostate-specific antigen (PSA) level of >0.2 ng/mL, two values at 0.2 ng/mL, or secondary treatment for an elevated PSA level. Predictors of BCR, metastases, and mortality were analysed using Cox proportional hazard models.

RESULTS

Of 5515 men in the SEARCH database, 4337 (79%) men met criteria for inclusion in the analysis. Of these, 2063 (48%) had NSM, 1902 (44%) had PSM, and 372 (8%) had CSM. On multivariable analysis, relative to NSM, men with CSM had a higher risk of BCR (hazard ratio [HR] 1.51, 95% confidence interval [CI] 1.25-1.82; P < 0.001) but a decreased risk of BCR when compared to those men with PSM (HR 2.09, 95% CI 1.86-2.36; P < 0.001). Metastases, prostate cancer-specific mortality and all-cause mortality did not differ based on margin status alone.

CONCLUSIONS

Management of men with CSM is a diagnostic challenge, with a disease course that is not entirely benign. The evaluation of other known risk factors probably provides greater prognostic value for these men and may ultimately better select those who may benefit from adjuvant therapy.

Modified risk stratification grouping using standard clinical and biopsy information for patients undergoing radical prostatectomy: Results from SEARCH

INTRODUCTION

Prostate cancer is a heterogeneous disease, and risk stratification systems have been proposed to guide treatment decisions. However, significant heterogeneity remains for those with unfavorable-risk disease.

METHODS

This study included 3335 patients undergoing radical prostatectomy without adjuvant radiotherapy in the SEARCH database. High-risk patients were dichotomized into standard and very high-risk (VHR) groups based on primary Gleason pattern, percentage of positive biopsy cores (PPBC), number of NCCN high-risk factors, and stage T3b-T4 disease. Similarly, intermediate-risk prostate cancer was separated into favorable and unfavorable groups based on primary Gleason pattern, PPBC, and number of NCCN intermediate-risk factors.

RESULTS

Median follow-up was 78 months. Patients with VHR prostate cancer had significantly worse PSA relapse-free survival (PSA-RFS, P < 0.001), distant metastasis (DM, P = 0.004), and prostate cancer-specific mortality (PCSM, P = 0.015) in comparison to standard high-risk (SHR) patients in multivariable analyses. By contrast, there was no significant difference in PSA-RFS, DM, or PCSM between SHR and unfavorable intermediate-risk (UIR) patients. Therefore, we propose a novel risk stratification system: Group 1 (low-risk), Group 2 (favorable intermediate-risk), Group 3 (UIR and SHR), and Group 4 (VHR). The c-index of this new grouping was 0.683 for PSA-RFS and 0.800 for metastases, compared to NCCN-risk groups which yield 0.666 for PSA-RFS and 0.764 for metastases.

CONCLUSIONS

Patients classified as VHR have markedly increased rates of PSA relapse, DM, and PCSM in comparison to SHR patients, whereas UIR and SHR patients have similar prognosis. Novel therapeutic strategies are needed for patients with VHR, likely involving multimodality therapy.

Metabolic reprogramming ensures cancer cell survival despite oncogenic signaling blockade

Lue et al. show that although inhibition of PI3K–AKT–mTOR signaling markedly decreased glycolysis and restrained tumor growth, these signaling and metabolic restrictions triggered autophagy. Survival of cancer cells was critically dependent on phospholipase A2 (PLA2) to mobilize lysophospholipids and free fatty acids to sustain fatty acid oxidation and oxidative phosphorylation.

There is limited knowledge about the metabolic reprogramming induced by cancer therapies and how this contributes to therapeutic resistance. Here we show that although inhibition of PI3K–AKT–mTOR signaling markedly decreased glycolysis and restrained tumor growth, these signaling and metabolic restrictions triggered autophagy, which supplied the metabolites required for the maintenance of mitochondrial respiration and redox homeostasis. Specifically, we found that survival of cancer cells was critically dependent on phospholipase A2 (PLA2) to mobilize lysophospholipids and free fatty acids to sustain fatty acid oxidation and oxidative phosphorylation. Consistent with this, we observed significantly increased lipid droplets, with subsequent mobilization to mitochondria. These changes were abrogated in cells deficient for the essential autophagy gene ATG5. Accordingly, inhibition of PLA2 significantly decreased lipid droplets, decreased oxidative phosphorylation, and increased apoptosis. Together, these results describe how treatment-induced autophagy provides nutrients for cancer cell survival and identifies novel cotreatment strategies to override this survival advantage.

Does Early Prostate Specific Antigen Doubling Time after Radical Prostatectomy, Calculated Prior to Prostate Specific Antigen Recurrence, Correlate with Prostate Cancer Outcomes? A Report from the SEARCH Database Group

PURPOSE

Short prostate specific antigen doubling time following recurrence after radical prostatectomy portends a poor prognosis. Prostate specific antigen doubling time is traditionally calculated using prostate specific antigen values 0.2 ng/ml or greater. We determined whether early prostate specific antigen doubling time, calculated from the first detectable postoperative prostate specific antigen up to and including the first recurrence value, correlates with prostate cancer outcomes.

MATERIALS AND METHODS

Cox models were used to examine the association between early prostate specific antigen doubling time and castration resistant prostate cancer, metastases, and all cause and prostate cancer specific mortality in 674 men who underwent radical prostatectomy between 1988 and 2014 and had a biochemical recurrence. Early prostate specific antigen doubling time was examined as a log transformed continuous and a categorical variable.

RESULTS

After adjusting for multiple clinicopathological characteristics, log transformed early prostate specific antigen doubling time was not associated with any outcome. However, when early doubling time was categorized as 15 or greater, 9 to 14.9, 3 to 8.9 and less than 3 months, on multivariable analysis men with early doubling time less than 3 months were at increased risk for castration resistant prostate cancer (HR 6.20, p = 0.004), metastases (HR 5.26, p = 0.001), prostate cancer specific mortality (HR 5.06, p = 0.026) and all cause mortality (HR 1.63, p = 0.065) compared to those with an early doubling time of 15 months or greater. However, the association with all cause mortality was not significant. Those with an early prostate specific antigen doubling time of 3 to 8.9 months were at increased risk for castration resistant prostate cancer (HR 3.56, p = 0.015), all cause mortality (HR 1.67, p = 0.006) and prostate cancer specific mortality (HR 3.17, p = 0.044) but not metastases (p = 0.13).

CONCLUSIONS

Early prostate specific antigen doubling time less than 9 months, calculated using prostate specific antigen values before and up to biochemical recurrence, is associated with an increased risk of castration resistant prostate cancer, metastases, and prostate cancer specific and all cause mortality among men with biochemical recurrence after radical prostatectomy. Early prostate specific antigen doubling time allows for risk stratification at biochemical recurrence and before prostate specific antigen doubling time is calculable, enabling these men to be referred for early aggressive secondary treatment and/or clinical trials.

Biopsy Detected Gleason Pattern 5 is Associated with Recurrence, Metastasis and Mortality in a Cohort of Men with High Risk Prostate Cancer

PURPOSE

We evaluated the relative risk of biochemical recurrence, metastasis and death from prostate cancer contributed by biopsy Gleason pattern 5 among men at high risk with Gleason 8-10 disease in the SEARCH (Shared Equal Access Regional Cancer Hospital) cohort.

MATERIALS AND METHODS

Men with biopsy Gleason sum 8-10 prostate cancer treated with radical prostatectomy were evaluated. The cohort was divided into men with Gleason 4 + 4 vs those with any pattern 5 (ie Gleason 3 + 5, 5 + 3, 4 + 5, 5 + 4 or 5 + 5). Predictors of biochemical recurrence, metastases, and prostate cancer specific and overall survival were analyzed using Kaplan-Meier, log rank test and Cox proportional hazards models.

RESULTS

We identified 634 men at high risk in the SEARCH database, of whom 394 (62%) had Gleason 4 + 4 and 240 (38%) had Gleason pattern 5 on biopsy. Baseline characteristics did not significantly differ between the groups. On multivariable analysis relative to Gleason 4 + 4 men at high risk with Gleason pattern 5 showed no difference in the risk of biochemical recurrence (HR 1.26, 95% CI 0.99-1.61, p = 0.065). However, they were at significantly greater risk for metastasis (HR 2.55, 95% CI 1.50-4.35, p = 0.001), prostate cancer specific mortality (HR 2.67, 95% CI 0.1.26-5.66, p = 0.010) and overall mortality (HR 1.60, 95% CI 1.09-2.34, p = 0.016).

CONCLUSIONS

Preoperative subclassification of high risk prostate cancer by biopsy Gleason grade (4 + 4 vs any Gleason pattern 5) identified men at highest risk for progression. Any Gleason 5 on biopsy is associated with a greater risk of metastasis, and prostate cancer specific and overall mortality. Grouping all Gleason 8-10 tumors together as high risk lesions may fail to fully stratify men at highest risk for poor outcomes.