Post-Relapse Survival in Diffuse Large B-Cell Lymphoma (DLBCL) Patients after Experiencing Therapy Failure Following Autologous Hematopoietic Cell Transplantation (auto-HCT)

Introduction The outcomes for DLBCL patients who relapse following auto-HCT have been historically poor. Using data from four transplant centers, we studied the outcomes of DLBCL patients who relapsed following auto-HCT and evaluated whether survival improved in the most recent time period with the advent of novel agents. Methods Eligibility criteria included adult (≥18 years) patients with DLBCL experiencing disease relapse following auto-HCT performed during 2006-2015. The time-period was stratified into two eras (era-1: 2006-2010 and era-2: 2011-2015). The primary endpoint was to determine post-relapse overall survival (PR-OS). Secondary endpoints included a comparison of PR-OS based on the timing of relapse post auto-HCT (early [≤1 year] vs late [>1 year]) and era of transplant (era-1 vs era-2). PR-OS was measured from the date of relapse following auto-HCT to date of death or last follow-up. Results Of the total 700 patients with DLBCL undergoing auto-HCT, 250 patients (36%) (n=113 from era-1 and n=137 from era-2) relapsed following auto-HCT between 2006 and 2015. Patient characteristics are shown in Table with a breakdown between the two eras. The median age was 59 years with male predominance. 92% were chemosensitive (n=230) at the time of auto-HCT. The median time to relapse post auto-HCT was 5.6 months (range: 0.8–96.6 months). Median lines of therapy for post auto-HCT relapse were 1 (range: 0-9), with the most common treatments being allogeneic HCT (21%), lenalidomide (18%) and on clinical trials (17%). Median follow-up of survivors post auto-HCT relapse was 39 months (range: 1-116 months). At 5-year post auto-HCT relapse, the PR-OS for the entire population was 25%, with a median PR-OS of 8.5 months (95% CI=6.3-11.5). Median PR-OS (in months) was significantly better for patients who had late relapse vs early relapse (56.4 [95% CI=23.7-∞] vs 5.5 [95% CI=4.1-7.2], respectively, p Conclusion In DLBCL patients who relapse following auto-HCT, there has been no significant improvement in PR-OS despite the advent of novel agents in the most recent era. More importantly, the outcomes are dismal for patients who relapse within 1 year of auto-HCT representing an urgent unmet need.