Bendamustine plus rituximab for relapsed or refractory diffuse large B cell lymphoma: a multicenter retrospective analysis

Bendamustine plus rituximab (BR) showed efficacy and safety in indolent lymphomas and mantle cell lymphoma. However, there were limited experiences of real-world practice of BR in diffuse large B cell lymphoma (DLBCL). In this study, we report the Korean experiences with BR in relapsed or refractory DLBCL who are not eligible for intensive chemotherapy and autologous stem cell transplantation. This is an observational, multicenter, retrospective analysis. Between December 2011 and December 2015, a total of 58 patients with relapsed or refractory DLBCL were treated with BR in 11 tertiary hospitals in Korea. Patients received an intravenous (IV) infusion of rituximab at a dose of 375 mg/m2 on day 1. On days 2 and 3, patients received an IV infusion of bendamustine at doses of 120 or 90 mg/m2. Median age was 69 (range 18-86), 74.1% had stage III or IV disease, and 67.2% showed high-intermediate or high International Prognostic Index scores at diagnosis. In an intention-to-treat analysis, 18 patients (31.0%) showed a complete response and 14 (24.1%) showed a partial response, resulting in an overall response rate of 55.1%. The median duration of the response was 3.7 months (range 1.0-47.2 months). The median progression-free survival was 3.9 months (95% confidence interval [CI], 2.4-5.4 months), and the median overall survival was 6.7 months (95% CI, 4.7-8.7 months). The most common grade 3/4 adverse event was neutropenia (n = 40; 68.9%). Febrile neutropenia was observed in 11 patients (18.9%). Grade 3/4 thrombocytopenia was observed in 34 patients (58.6%). Our study confirmed the high efficacy and acceptable toxicity profile of BR in relapsed or refractory DLBCL patients. However, we need to closely observe the higher tendency of grade 3/4 hematological toxicities in Korean patients.