Nastoupil, Loretta J.

SummaryBendamustine (B) with rituximab (R) is a standard frontline treatment for medically fit follicular lymphoma (FL) patients. The safety and efficacy of maintenance rituximab (MR) after BR induction has not been formally compared to observation for FL, resulting in disparate practice patterns. Prospective trials have shown benefit of MR after R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) or R‐CVP (rituximab, cyclophosphamide, vincristine, prednisone), yet recent data from the GALLIUM study comparing outcomes of patients treated with chemotherapy with R or obinutuzumab (G) showed higher than anticipated fatal adverse events with BR/BG. In order to assess the efficacy and tolerability of MR after BR, we retrospectively collected data on 640 newly diagnosed patients treated with FL. We found that patients who achieved partial remission (PR) after ≥4 cycles of BR had improved duration of response (DOR) with MR vs. no maintenance, whereas those in complete remission did not. These findings were confirmed in a validation cohort. In the entire study population, the known fatal adverse event rate after BR was 2·5% and did not significantly differ in those receiving MR versus no maintenance. [Correction added on 14 January 2019, after online publication: The preceding sentence has been corrected in this current version.] Within the limitations inherent to retrospective analysis, these data suggest that FL patients with a PR to BR experience prolongation of remission with MR with an acceptable safety profile.

SummaryTo examine the effectiveness of an initial management strategy of watchful waiting for follicular lymphoma (FL) in clinical practice, we compared outcomes for patients diagnosed 2004–2007 in the United States initially managed with watchful waiting with outcomes following initial rituximab monotherapy and chemoimmunotherapy. In total, 1754 stage II–IV patients in the National LymphoCare Study underwent watchful waiting (n = 386), rituximab monotherapy (n = 296) or rituximab plus chemotherapy (n = 1072) as initial management strategy. Female patients and those who received treatment in the Northeast or in an academic setting more commonly underwent watchful waiting versus initial chemoimmunotherapy; whereas patients with grade 3 histology, anaemia, elevated lactate dehydrogenase, extranodal involvement, B symptoms or performance status ≥1 more commonly received chemoimmunotherapy. Although time to new treatment and progression‐free survival following first‐ and second‐line therapy were improved with chemoimmunotherapy, and time to chemotherapy was improved with rituximab monotherapy, there were no differences in overall survival between watchful waiting and chemoimmunotherapy or rituximab monotherapy. With 8‐year overall survival estimates of 74%, initial management with watchful waiting in the context of sequential therapy remains a viable option for FL patients in the modern era. This trial was registered at www.clinicaltrials.gov (NCT00097565).

BACKGROUNDThe authors examined the “real‐world” effectiveness of rituximab (R) maintenance therapy (R‐maintenance) compared with observation after R‐based induction therapy in patients with previously untreated follicular lymphoma (FL) in the United States.METHODSThe National LymphoCare Study is a prospective, multicenter, observational study that enrolled > 2700 untreated patients with FL diagnosed from 2004 to 2007 at 265 sites in the United States. Among these, patients who achieved at least stable disease after R‐based induction therapy were eligible for the current analysis. Patients who initiated R‐maintenance within 215 days of completing induction therapy were categorized as the R‐maintenance group, and those who did not initiate therapy during this period were categorized as the observation group. The objective of the current study was to determine the effect of R‐maintenance on progression‐free survival (PFS), time to next treatment (TTNT), and overall survival (OS).RESULTSA total of 1439 patients completed R‐based induction therapy, 1186 of whom met all inclusion criteria (541 patients received R‐maintenance and 645 patients were observed). Characteristics that were found to be predictive of receiving R‐maintenance were histology grade (1/2), Ann Arbor stage of disease (III/IV), geographic region (region other than the West), and practice setting (community practice). With a median follow‐up of 5.7 years, R‐maintenance was associated with superior PFS (hazards ratio [HR], 0.68; 95% confidence interval [95% CI], 0.56‐0.84 [P = .0003]) and TTNT (HR, 0.66; 95% CI, 0.52‐0.84 [P = .0007]). No significant difference in OS was observed (HR, 0.81; 95% CI, 0.58‐1.14 [P = .23]).CONCLUSIONSR‐maintenance in patients with FL and at least stable disease after R‐based induction therapy provided significantly longer PFS and TTNT in comparison with observation, but no significant difference in OS was observed with 5‐years of follow‐up. This comparative effectiveness study aligns with the results of randomized trials suggesting that similar outcomes occur with R‐maintenance in FL with the treatment variations observed in clinical practice. Cancer 2014;120:1830–1837. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.