A multi-center retrospective analysis of patients with relapsed/refractory follicular lymphoma after third-line chemotherapy

The overall outcome of patients with advanced-stage follicular lymphoma (FL) has improved significantly. However, some patients still develop multiple relapsed/refractory FL (RRFL). To address the still-limited data on this population, we performed this multi-center retrospective study. We analyzed 41 patients who received third-line treatment for RRFL at 8 institutes. The median age at diagnosis was 59 years (range, 38-70). The median progression-free survival (PFS) and probability of PFS at 2 years were 1.61 years and 39.4%, respectively, after third-line chemotherapy, and 0.45 years and 19.0%, respectively, after fourth-line chemotherapy. Objective response (OR) after third-line chemotherapy was achieved in 24 patients (53.7%). Bendamustine (Ben)-based regimens were associated with a significantly higher OR rate than other regimens (77.8% vs. 40.0%, respectively,P = 0.025). The median overall survival (OS) and probability of OS at 2 years were 4.71 years and 65.9%, respectively, after third-line chemotherapy, and 1.01 year and 45.1%, respectively, after fourth-line chemotherapy. In conclusion, this study had a small sample size and retrospective design, but it was able to demonstrate poor response rate and duration in patients with multiple RRFL, particularly after fourth-line chemotherapy. The optimal treatment strategy in this population should be clarified, including possibly hematopoietic stem cell transplantation.