A Nationwide Analysis of Clinical Trial Participation for Common Hepato-pancreato-Biliary Malignancies Demonstrates Survival Advantages for Subsets of Trial Patients But Disparities and Infrequency of Enrollment

Abstract

Introduction: Clinical trial participation for patients with hepato-pancreato-biliary(HPB) malignancies is not well defined. We described overall trial participation and factors associated with enrollment. We analyzed the association and effect of trial enrollment on overall survival(OS). Methods: The National Cancer Database(2004-2017) was queried for patients with common HPB malignancies (pancreatic adenocarcinoma[PDAC] & neuroendocrine tumors, hepatocellular carcinoma[HCC], biliary tract cancers[BTC]). Multivariable logistic regression was used to identify factors associated with trial enrollment. OS was analyzed by multivariable Cox regression. Inverse probability weighted Cox regression was utilized to determine the marginal effect of trial enrollment on OS. Results: A total of 511,639 patients were included; 1573 patients(0.3%) were enrolled in trials; 1214(0.4%) with pancreatic malignancies, 217(0.14%) with HCC, and 106(0.15%) with BTC. On multivariable analysis, HCC and BTC were associated with lower likelihood of enrollment compared with pancreatic malignancy. Non-Hispanic Black and Hispanic races were associated with lower likelihood of enrollment compared with non-Hispanic White race. Treatment at academic facilities and presence of metastatic disease were associated with higher likelihood of enrollment. Trial enrollment was associated with higher OS for PDAC, metastatic HCC, and metastatic BTC(Figure 1A). On weighted Cox analysis, trial enrollment exhibited an OS advantage for PDAC and metastatic HCC(Figure 1B). Conclusions: Nationally, fewer than 1% of patients with HPB malignancies were enrolled in clinical trials. Trial enrollment appears to be associated with improved OS in subsets of patients with HPB malignancies. There are racial, sociodemographic, and facility-based disparities in clinical trial enrollment and these represent areas for targeted improvement.