Average treatment effect of facility hepatopancreatobiliary cancer volume on survival of non-resected pancreatic adenocarcinoma

Understanding surgical attrition for "resectable" pancreatic cancer

OBJECTIVES

We used a novel combined analysis to evaluate various factors associated with failure to undergo surgery in non-metastatic pancreatic cancer.

METHODS

We identified rates of surgery and reasons for surgical attrition from clinical trials, which studied neoadjuvant therapy in resectable pancreatic cancer. Next, we queried the National Cancer Database (NCDB) for Stage I-III, T1-3 pancreatic adenocarcinoma patients. We investigated the rates and factors associated with the receipt of surgery. Finally, we evaluated variable importance predicting the receipt of surgery.

RESULTS

In clinical trials, 25-30 % of patients did not undergo surgery, mostly due to disease progression. In the NCDB, the overall surgical rate was only 49 %, but increased to 67 % in a curated cohort meant to mirror clinical trial patients. Patients treated at low-volume institutions (OR = 0.64, 95 % CI: 0.61-0.67) and who were uninsured (OR = 0.56, 95 % CI: 0.52-0.62) and Medicaid-insured (OR = 0.67, 95 % CI: 0.64-0.71) were less likely to receive potentially curative surgery.

CONCLUSION

We have identified a realistic target surgery rate of 70%-75 % in potentially-resectable pancreatic cancer. While attrition to pancreatic cancer surgery is mostly due to tumor biology, our study identified the most important non-medical barriers, such as facility volume and insurance, affecting pancreatic cancer surgery.

Surgical Resection Alone is Associated With Higher Long-Term Survival Than Multiagent Chemotherapy Alone for Patients With Localized Biliary Tract Cancers

INTRODUCTION

We compared long-term survival of patients with localized biliary tract cancers (BTCs) treated with either surgical resection or multiagent chemotherapy.

METHODS

Patients with localized BTC [gallbladder adenocarcinoma, extrahepatic cholangiocarcinoma, intrahepatic cholangiocarcinoma] were identified within the National Cancer Database (2010-2017). Piecewise-constant hazard modeling was used to estimate hazard ratios (HRs) at prespecified intervals: 0-30 d, 31-60 d, 61-90 d, and >90 d post-treatment.

RESULTS

A total of 5988 patients with localized BTC were identified: 2697 (45.0%) received multiagent chemotherapy and 3291 (55.0%) underwent surgical resection. Patients with gallbladder adenocarcinoma or extrahepatic cholangiocarcinoma who were treated with surgical resection had an associated decline in overall survival (OS) as compared to those treated with multiagent chemotherapy within 0-30 d of treatment initiation (gallbladder adenocarcinoma [adjusted HR = 3.94, 95% confidence interval [CI]: 1.77-8.80]; extrahepatic cholangiocarcinoma [adjusted HR = 4.88, 95% CI: 2.76-8.61]). However, there was an associated improvement in OS for patients treated with surgical resection after 90 d from treatment initiation (gallbladder adenocarcinoma [adjusted HR = 0.36, 95% CI: 0.28-0.46]; extrahepatic cholangiocarcinoma [adjusted HR = 0.27, 95% CI: 0.24-0.32]). Among patients with intrahepatic cholangiocarcinoma, those who underwent surgical resection had an associated improvement in OS at 31-60 d (adjusted HR = 0.63, 95% CI: 0.40-0.99) and a further associated increase in OS at 61-90 d (adjusted HR = 0.34, 95% CI: 0.21-0.54) and after 90 d (HR = 0.23, 95% CI: 0.21-0.27) of treatment initiation.

CONCLUSIONS

For patients with localized BTC, surgical resection alone is associated with improved long-term survival outcomes compared to multiagent chemotherapy alone.

Surgical management of 1- to 2-cm neuroendocrine tumors of the appendix: Appendectomy or right hemicolectomy?

BACKGROUND

The surgical management of 1- to 2-cm neuroendocrine tumors of the appendix is an area of debate. We analyzed the clinical outcomes of appendectomy and compared them to right hemicolectomy.

METHODS

We queried the National Cancer Database to identify patients treated for 1- to 2-cm ANETs from 2004 to 2018. Patients were stratified by surgical approach (appendectomy vs. hemicolectomy). Multivariable models were used to identify factors associated with the choice of surgical approach and the association between surgical approach and overall survival.

RESULTS

Of the 3,189 patients we included, 1,573 (49.3%) underwent right hemicolectomy and 1,616 (50.7%) appendectomy. The appendectomy rate increased from 37.7% in 2004 to 58.9% in 2018. On multivariable analysis, patients with grade 2 and 3 tumors were less likely to undergo appendectomy alone (odds ratio = 0.41, 95% confidence interval = 0.26-0.66). Longer travel distance was associated with a higher likelihood of undergoing appendectomy (odds ratio = 2.52, 95% confidence interval = 1.15-5.51). After adjusting for tumor grade, appendectomy alone had similar survival to hemicolectomy (hazard ratio = 1.03, 95% confidence interval = 0.67-1.59).

CONCLUSION

In this updated analysis of the National Cancer Database, right hemicolectomy was not associated with improved overall survival compared to appendectomy alone for 1- to 2-cm neuroendocrine tumors of the appendix. Although patients with grade 2 or 3 tumors are more likely to undergo right hemicolectomy, this procedure may not improve their treatment or overall outcome.

Disparities in guideline-compliant care for patients with pancreatic ductal adenocarcinoma at minority-versus non-minority-serving hospitals

BACKGROUND

We examined disparities in guideline-compliant care at minority-serving hospitals (MSH) versus non-MSH among patients with localized or metastatic pancreatic adenocarcinoma (PDAC).

METHODS

Patients with PDAC were identified within the National Cancer Database (2004-2018). Guideline-compliant care was defined as surgery + chemotherapy ± radiation therapy for localized and chemotherapy for metastatic disease. Facilities in the top decile of minority patients treated were considered MSH.

RESULTS

A total of 190,950 patients were identified and most (59.6%) had metastatic disease. Overall, 6.4% of patients with localized and 8.2% of patients with metastatic disease were treated at MSH. Patients treated at MSH were less likely to receive guideline-compliant care (localized: OR = 0.78, 95% CI: 0.67-0.91; metastatic: OR = 0.77, 95% CI: 0.67-0.88). Minority patients were less likely to receive guideline-compliant care at non-MSH (localized: OR = 0.71, 95% CI: 0.67-0.75; metastatic: OR = 0.85, 95% CI: 0.82-0.89) or MSH (localized: OR = 0.85, 95% CI: 0.74-0.98; metastatic: OR = 0.91, 95% CI: 0.82-0.99). Patients treated at non-MSH or MSH who received guideline-compliant care were more likely to have higher OS regardless of stage or race.

CONCLUSIONS

MSH patients were less likely to receive guideline-compliant care and minority patients were less likely to receive guideline-compliant care regardless of MSH status. Guideline-compliant care was associated with improved OS.

Differences in the surgical management of early-stage hepatocellular carcinoma at minority versus non-minority-serving hospitals

BACKGROUND

We examined differences in surgical intervention at minority-serving hospitals versus non-minority-serving hospitals among patients with early-stage hepatocellular carcinoma. We also investigated associations between surgical management and overall survival, stratified by minority-serving hospital status.

METHODS

Patients with early-stage hepatocellular carcinoma, defined as cT1, were identified within the National Cancer Database (2004-2018). The primary outcome was surgical intervention (resection, ablation, or transplantation). The proportion of minority (non-Hispanic Black or Hispanic) patients treated at each facility was determined, and hospitals in the top decile were considered minority-serving hospitals.

RESULTS

A total of 46,703 patients with early-stage hepatocellular carcinoma were identified, of whom 4,214 (9.0%) were treated at minority-serving hospitals. Patients treated at minority-serving hospitals were less likely to undergo surgical intervention than patients treated at non-minority-serving hospitals (odds ratio = 0.87, 95% confidence interval: 0.81-0.94). Minority patients treated at non-minority-serving hospitals were less likely to undergo surgical intervention than White patients (odds ratio = 0.86, 95% confidence interval: 0.82-0.90) and had a further associated decrease in the likelihood of surgical intervention when treated at minority-serving hospitals (odds ratio = 0.81, 95% confidence interval: 0.69-0.94). Regardless of minority-serving hospital status, surgery was associated with improved overall survival. There were no clinically meaningful differences in overall survival between White and minority patients who underwent surgery either at minority-serving hospitals or non-minority-serving hospitals.

CONCLUSIONS

Patients with early-stage hepatocellular carcinoma had an associated decrease in the likelihood of surgical intervention when treated at minority-serving hospitals. Minority patients treated at minority-serving hospitals had an associated decrease in the likelihood of surgery, but to a lesser extent when treated at non-minority-serving hospitals. Surgery was associated with improved overall survival regardless of minority or minority-serving hospital status.

Adjuvant Chemotherapy Is Associated with Improved Survival for Stage III Colon Cancer When Initiated Beyond 8 Weeks

BACKGROUND

The National Comprehensive Cancer Network (NCCN) guidelines recommend adjuvant chemotherapy (AC) within 6-8 weeks of surgical resection for patients with stage III colon cancer. However, postoperative complications or prolonged surgical recovery may affect the receipt of AC. The aim of this study was to assess the utility of AC for patients with prolonged postoperative recovery.

METHODS

We queried the National Cancer Database (2010-2018) for patients with resected stage III colon cancer. Patients were categorized as having either normal or prolonged length of stay (PLOS: >7 days, 75th percentile). Multivariable Cox proportional hazard regression and logistic regressions were used to identify factors associated with overall survival and receipt of AC.

RESULTS

Of the 113,387 patients included, 30,196 (26.6%) experienced PLOS. Of the 88,115 (77.7%) patients who received AC, 22,707 (25.8%) initiated AC more than 8 weeks after surgery. Patients with PLOS were less likely to receive AC (71.5% vs. 80.0%, OR: 0.72, 95%CI=0.70-0.75) and displayed inferior survival (75 vs. 116 months, HR: 1.39, 95%CI=1.36-1.43). Receipt of AC was also associated with patient factors such as high socioeconomic status, private insurance, and White race (p<0.05 for all). AC within and after 8 weeks of surgery was associated with improved survival for patients with both normal LOS and PLOS (normal LOS: <8 weeks HR: 0.56, 95% CI: 0.54-0.59, >8 weeks HR: 0.68, 95% CI: 0.65-0.71; PLOS: <8 weeks HR: 0.51, 95% CI: 0.48-0.54, >8 weeks HR: 0.63, 95% CI 0.60-0.67). AC was associated with significantly improved survival if initiated up to 15 weeks postoperatively (normal LOS: HR: 0.72, 95%CI=0.61-0.85; PLOS: HR: 0.75, 95%CI=0.62-0.90), and very few patients (<3.0%) initiated AC beyond this time.

CONCLUSION

Receipt of AC for stage III colon cancer may be affected by surgical complications or otherwise prolonged recovery. Timely and even delayed AC (>8 weeks) are both associated with improved overall survival. These findings highlight the importance of delivering guideline-based systemic therapies, even after complicated surgical recovery.

Impact of Medicaid Expansion on the Treatment and Outcomes of Intrahepatic Cholangiocarcinoma

INTRODUCTION

The Affordable Care Act increased insurance coverage for patients residing in states that expanded Medicaid coverage, but its impact on the outcomes of intrahepatic cholangiocarcinoma (ICC) is not clear. Therefore, we examine the impact of Medicaid expansion (ME) on access to treatment and outcomes of ICC.

METHODS

We queried the National Cancer Database (NCDB) data for patients with a diagnosis of ICC (2010-2018). Difference-in-difference (DID) analysis was performed to assess the impact of January 2014 ME on curative-intent surgical resection, multimodal therapy, neoadjuvant chemotherapy, 30-day mortality, and overall survival (OS).

RESULTS

Of the 2150 patients included in the study,1574 (73.2%) and 576 (26.8%) patients lived in non-ME and ME states, respectively. On adjusted DID, ME was independently associated with receipt of curative-intent surgical resection (DID coefficient: 0.05, 95% confidence interval [95% CI]: 0.04-0.06, p = 0.002) and multimodal therapy (DID coefficient: 0.08, 95% CI: 0.06-0.10, p = 0.004). In addition, ME was associated with improved OS in ME states (hazard ratio [HR]: 0.73, 95% CI: 0.62-0.87, p = 0.001) but not in non-ME states (HR: 0.95, 95% CI: 0.80-1.12, p = 0.536).

CONCLUSION

ME status consistently predicted increased utilization of care processes that improved ICC outcomes, including greater rates of curative-intent surgery and multimodal therapy.

Understanding Factors Leading to Surgical Attrition for "Resectable" Gastric Cancer

OBJECTIVES

We used a novel combined analysis to evaluate various factors associated with failure to surgical resection in non-metastatic gastric cancer.

METHODS

We identified factors associated with the receipt of surgery in publicly available clinical trial data for gastric cancer and in the National Cancer Database (NCDB) for patients with stages I-III gastric adenocarcinoma. Next, we evaluated variable importance in predicting the receipt of surgery in the NCDB.

RESULTS

In published clinical trial data, 10% of patients in surgery-first arms did not undergo surgery, mostly due to disease progression and 15% of patients in neoadjuvant therapy arms failed to reach surgery. Effects related to neoadjuvant administration explained the increased attrition (5%). In the NCDB, 61.7% of patients underwent definitive surgery. In a subset of NCDB patients resembling those enrolled in clinical trials (younger, healthier, and privately insured patients treated at high-volume and academic centers) the rate of surgery was 79.2%. Decreased likelihood of surgery was associated with advanced age (OR 0.97, p < 0.01), Charlson-Deyo score of 2+ (OR 0.90, p < 0.01), T4 tumors (OR 0.39, p < 0.01), N+ disease (OR 0.84, p < 0.01), low socioeconomic status (OR 0.86, p = 0.01), uninsured or on Medicaid (OR 0.58 and 0.69, respectively, p < 0.01), low facility volume (OR 0.64, p < 0.01), and non-academic cancer programs (OR 0.79, p < 0.01).

CONCLUSION

Review of clinical trials shows attrition due to unavoidable tumor and treatment factors (~ 15%). The NCDB indicates non-medical patient and provider characteristics (i.e., age, insurance status, facility volume) associated with attrition. This combined analysis highlights specific opportunities for improving potentially curative surgery rates.

Average treatment effect of facility hepatopancreatobiliary malignancy case volume on survival of patients with nonoperatively managed hepatobiliary malignancies

BACKGROUND

Surgical volume-outcome relationships have been described for a variety of procedures. There is scant literature on total institutional volume and outcomes in patients who are nonoperatively managed. We examined the average treatment effect of total hepatopancreatobiliary malignancy case volume on survival outcomes of patients with nonresected hepatobiliary malignancies.

METHODS

We identified patients with hepatopancreatobiliary malignancies [pancreatic adenocarcinoma, pancreatic neuroendocrine neoplasms, hepatocellular carcinoma, biliary tract cancers] within the National Cancer Database (2004-2018). We determined percentile thresholds based on the total annual hepatopancreatobiliary malignancy case volume. We then identified nonoperatively managed patients with hepatocellular carcinoma or biliary tract cancers. We used inverse probability-weighted Cox regression to estimate the effect of facility volume on overall survival.

RESULTS

We identified 710,988 patients with hepatopancreatobiliary malignancies. Total annual hepatopancreatobiliary malignancy case volume of 32, 71, and 177 cases/year corresponded to the 25th, 50th, and 75th percentiles. A total of 96,420 with hepatocellular carcinoma and 52,627 patients with biliary tract cancers were managed nonoperatively. In patients with hepatocellular carcinoma or biliary tract cancer, treatment at ≥25th, ≥50th, and ≥75th percentile facilities was associated with improved median, 1-, 2-, and 3-year overall survival compared with treatment at lower-percentile facilities. On inverse probability-weighted Cox analysis, treatment at higher-percentile facilities resulted in a lower hazard of death. Consistent findings were observed in patients with early or intermediate/advanced hepatocellular carcinoma or metastatic biliary tract cancers.

CONCLUSION

Patients with nonoperatively managed hepatocellular carcinoma or biliary tract cancer who receive treatment at higher-volume facilities have improved survival outcomes. These data suggest regionalization of care for patients with hepatocellular carcinoma or biliary tract cancer to high-volume centers may improve survival.

Trends and disparities in the utilization of systemic chemotherapy in patients with metastatic hepato-pancreato-biliary cancers

BACKGROUND

We described trends and disparities in utilization of systemic chemotherapy in metastatic hepato-pancreato-biliary (HPB) cancers.

METHODS

We queried the National Cancer Database for metastatic HPB cancers [hepatocellular carcinoma (HCC), biliary tract cancers (BTC), pancreatic adenocarcinoma (PDAC)]. We used multivariable analysis to examine the factors associated with utilization of systemic chemotherapy. We utilized marginal structural logistic models to estimate the effect of health insurance, facility type, or facility volume on utilization of systemic chemotherapy.

RESULTS

We identified 162,283 patients with metastatic HPB cancers: 23,923 (14.7%) had HCC, 26,766 (16.5%) had BTC, and 111,594 (68.8%) had PDAC. A total of 37.2% patients with HCC, 55.6% with BTC, and 56.4% with PDAC received chemotherapy. Age ≥70 years and Charlson-Deyo score ≥2 were associated with lower likelihood of receiving chemotherapy across all cancers. Patients with private health insurance had higher receipt of chemotherapy. Receiving treatment at academic facilities had no effect on the receipt of chemotherapy. Treatment of patients with HCC or PDAC at high-volume facilities resulted in higher receipt of chemotherapy.

CONCLUSION

A significant proportion of patients with metastatic HPB cancers do not receive systemic chemotherapy. Several disparities in administration of chemotherapy for metastatic HPB cancers exist.

Disparities in treatment and survival for patients with isolated colorectal liver metastases

BACKGROUND

Surgical resection improves survival for patients with isolated colorectal liver metastasis. National studies on the disparities related to this topic are limited; therefore, we investigated factors that affect surgical treatment and survival.

METHODS

We queried the National Cancer Database (2010-2017) for patients with isolated synchronous colorectal liver metastasis. Multivariable logistic regression and Cox proportional hazard regressions were used to identify factors associated with surgical resection, treatment at high-volume facilities, and overall survival.

RESULTS

Of 34,050 patients with isolated colorectal liver metastasis, surgical resection (n = 7,810; 23.0%) was more likely among patients who were of high socioeconomic status (odds ratio = 1.16; 95% confidence interval, 1.04-1.31), traveled long distance for treatment (odds ratio = 1.48; 95% confidence interval, 1.31-1.66), and were treated at high-volume facilities (odds ratio = 4.86; 95% confidence interval, 14.45-5.30). Black patients were less likely to undergo resection (odds ratio = 0.75; 95% confidence interval, 0.69-0.82). Treatment at high-volume facility was more common among patients who were Black (odds ratio = 1.14; 95% confidence interval, 1.07-1.21), were of high socioeconomic status (socioeconomic status index 7: odds ratio = 1.21; 95% confidence interval, 1.11-1.31), and traveled long distance (odds ratio = 4.03; 95% confidence interval, 3.63-4.48) and less likely for nonmetropolitan residents and those of low socioeconomic status (P < .05). Patients of high socioeconomic status and those who traveled long distance, were treated at high-volume facilities, underwent surgical resection, and received perioperative chemotherapy had an associated survival advantage (P < .05 for all), whereas Black race was associated with poorer overall survival (P < .05).

CONCLUSION

Nonmedical patient factors, such as race, socioeconomic status, and geography, are associated with treatment and survival for isolated colorectal liver metastases. Disparities persist after adjusting for surgical resection and treatment facility. These barriers must be addressed to improve care for vulnerable cancer patients.