Bendamustine-Rituximab (BR) Combination in Low Grade B-Cell Lymphoproliferative Disorders (LPD): A Community Oncology Experience

Introduction:

Low-grade B-Cell LPDs are indolent Non-Hodgkin’s Lymphoma (NHL) that are incurable with current therapeutic options. BR chemoimmunotherapy has demonstrated remarkable effectiveness in these patients. Here we report our experience with BR in low-grade B Cell LPD subtypes.

Method:

Between October 2011 and May 2014, we treated 25 patients with a diagnosis of low-grade B-Cell LPD with a planned BR regimen of 6 cycles. The median age was 64 years (range 41-91), 15/10 M/F – a ratio of 3:2. LPD subtype included Chronic Lymphocytic Leukemia (CLL) 5, Small Lymphocytic Lymphoma (SLL) 3, Follicular Lymphoma (FL) 6, Marginal Zone Lymphoma (MZL) 2, Mantle Cell Lymphoma (MCL) 2, Mucosa-associated Lymphoid Tissue (MALT) 3, and Lymphoplasmacytic Lymphoma (LPL) 4. Twenty two (88%) were stages III or IV. Ten had received prior treatments. 15 had BR as first treatment. The regimen consisted of Bendamustine (B) 90 mg/m2 (on days 1&2 and Rituximab (R) 375 mg/m2 on day1 given every 28 days.

Results:

Seventeen (68%) completed the entire 6 planned cycles. 14 (56%) required treatment delays due to various toxicities. In 5 (20%) chemo was discontinued early for toxicity. The most common non-hematologic toxicity was fatigue 11 (44%), and skin rash 5 (20%). The grade III/IV hematologic toxicity was as follows neutropenia (3) anemia (9) and thrombocytopenia (2).

The overall response rate (ORR) was 92% (23 pts) with 18 (72%) Partial Responses (PR), and 5 (20%) Complete Responses (CR). Twenty four (96%) continued to have remission with no progression noted during follow-up. One patient with 17p del CLL progressed after 3 months with Richters transformation to diffuse large B cell NHL. The median duration of response was 17 months, with a range from 2 months – 38 months.

Conclusion:

In all LPD subtypes, despite the observed toxicities requiring treatment delays and dose modifications, 96% patients attained significantly long lasting remissions. Although this review included a comparatively small number of patients, our experience shows that BR is a highly effective chemo immunotherapy in all subtypes of Low-Grade B-Cell LPD – suggestive of altering the natural biology of this disease. For more definitive results, the study should be inclusive of a larger number of patients and prolonged follow-ups.