High risk patients with diffuse large B cell lymphoma are not enrolled on clinical trials.

Abstract

e19058 Background: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. In this study, we explore reasons for non-enrollment in clinical trials for DLBCL and implications on trial design and interpretation. Methods: This is a retrospective analysis of patients (pts) with a pathological diagnosis of DLBCL or high grade B-cell lymphoma (HGBL) at University of Rochester (4/14-6/16) and New York-Presbyterian Hospital/Weill Cornell Medicine (NYP/WCM) (4/14-4/17).Ten clinical trials were opened during this time. Participants were divided into 3 groups: those treated in trial, those not enrolled in trial because of need for urgent treatment, and those not enrolled in trial for any other reason. We used a center-stratified Cox proportional hazards model to estimate association of trial enrollment with progression-free survival (PFS; time from start of treatment until progression/death or the last date the pt was known to be progression free) and overall survival (OS). Results: We identified 263 pts; 17% (n = 45) enrolled in a trial. Reasons for non-enrollment included not meeting eligibility criteria (n = 98), physician choice (n = 50), and pt choice (n = 38). For 32 pts, reasons were unclear. Of the 50 pts who were not enrolled because of physician choice, the primary reason for non-enrollment was the need for urgent treatment (n = 46). Pts who needed urgent treatment had higher risk clinical features compared with pts in trial (Table). Compared with those treated in trial and those not enrolled in trial for any other reason, those not enrolled in trial due to need for urgent treatment had an inferior PFS (HR 2.61, 95% CI 1.23–5.16) and OS (HR 2.27, 95% CI 1.21–4.06). Conclusions: At 2 academic institutions, 52% of patients with DLBCL or HGBL required urgent chemotherapy and failed to enroll on trials. Exclusion of such patients limits the applicability and generalizability of clinical trials in DLBCL. This barrier must be overcome so clinical trials may better reflect true DLBCL demographics. [Table: see text]