Currently, comparative data are scarce in the literature to help guide treatment for previously untreated patients with Waldenström’s macroglobulinemia (WM), a rare subtype of non-Hodgkin lymphoma. In this study, researchers compared 3 commonly used regimens in WM: rituximab plus bendamustine (R-Benda); dexamethasone, rituximab, and cyclophosphamide (DRC); and bortezomib, dexamethasone, and rituximab (BDR).
This single-institution, retrospective study included patients with active WM, seen between 2000 and 2018, who received R-Benda, DRC, or BDR as primary therapy.
The study included 222 patients with active WM (R-Benda, n = 83; DRC, n = 92; BDR, n = 47). The median follow-up for the entire cohort was 4.0 years. Most baseline characteristics were similar across the 3 cohorts.
In terms of efficacy, objective response rates were 95%, 76%, and 81%, and major response rates were 93%, 46%, and 63% for R-Benda, DRC, and BDR, respectively. Median event-free survival was not reached, 4.3 years, and 2.1 years for R-Benda, DRC, and BDR, respectively. The difference in median 4-year overall survival between the 3 groups was not significant.
Hematologic and nonhematologic toxicities were similar across the 3 groups except for higher neuropathy leading to treatment discontinuation in patients who received BDR. Grade 3 neuropathy requiring treatment discontinuation was seen in 13% of patients treated with BDR.
This retrospective analysis showed that several efficacy outcomes with frontline R-Benda were superior in comparison with frontline DRC or BDR in patients with WM. In addition to the inherent limitations of retrospective studies, the researchers cautioned that shorter follow-up in the R-Benda group (median 2.2 years) versus the DRC (median 5.7 years) and BDR (median 4.7 years) groups may limit accurate assessment of long-term outcomes with R-Benda.
Abstract 7509; Abeykoon JP, et al.