The role of additional chemotherapy prior to autologous HCT in patients with relapse/refractory DLBCL in partial remission—A retrospective multicenter study

Objectives: To evaluate the role of additional chemotherapy before autologous hematopoietic cell transplantation (HCT) in patients with relapse/refractory diffuse large B-cell lymphoma (DLBCL) who achieve partial remission following first salvage therapy. Methods: We conducted a multicenter retrospective study of all adult patients with DLBCL who underwent HCT between 2008 and 2020 and achieved partial response (PR) after the first salvage and were either referred directly to HCT (n = 47) or received additional salvage therapy before HCT (n = 22). Results: Post-HCT CR rate and progression-free survival were comparable between the two groups (66% vs. 68%, p =.86 and median not reached vs. 10.2 months [95% confidence interval, CI 7.1–12.3], p =.27, respectively). Median overall survival (OS) and estimated 3-year OS favored patients who were directly referred to HCT (105.8 [95% CI 63–148] months vs. 14.5 [95% CI 0–44] months, p =.035, and 65% [95% CI 51%–75%] vs. 40% [95% CI 21%–53%], p =.035, respectively). In Cox regression model, while International Prognostic Index and primary refractory versus relapse disease did not impact OS, allocation to a second salvage regimen and older age were both associated with inferior survival (hazard ratio [HR] = 2.57 95% CI 1.1–5.8, p =.023 and HR = 1.04 95% CI 0.99–1.2, p =.064, respectively). Conclusions: Referring patients with chemotherapy-sensitive disease in PR directly to HCT is associated with better OS compared to those receiving additional lines of treatment.