According to the results of a study published in the Journal of Clinical Oncology, autologous stem-cell transplant (ASCT) as first-line treatment for mantle cell lymphoma (MCL) appears to be underutilized in the US community setting, with only approximately 25% of transplant-eligible patients undergoing ASCT. Additionally, no significant association between the receipt of ASCT and overall survival was observed in transplant-eligible patients, and maintenance rituximab after bendamustine plus rituximab (BR) was associated with longer survival compared with BR alone in maintenance-eligible patients.
Using data from 2 large, independent, real-world cohorts, researchers retrospectively evaluated treatment patterns and outcomes in patients with MCL and assessed the impact of ASCT in patients aged <65 years and maintenance rituximab after BR or rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP).
The researchers identified records of patients in the Flatiron Health database diagnosed with MCL between 2011 and 2021 and treated in US community oncology settings. They evaluated treatment patterns and outcomes and validated the efficacy findings with ASCT and maintenance rituximab in an independent cohort of patients treated at 12 academic centers.
A total of 3614 patients had documented first-line treatment. BR was the most commonly used regimen (41.5%). Among patients aged <65 years (n=1265), 30.5% received cytarabine-based induction, and 23.5% received ASCT.
The researchers found no significant association between ASCT and real-world time to next treatment (hazard ratio [HR], 0.84; 95% CI, 0.68-1.03; P =.10) or overall survival (HR, 0.86; 95% CI, 0.63-1.18; P =.4) among patients who were considered eligible for ASCT. Among patients considered who were considered eligible for maintenance rituximab, they found that maintenance rituximab after BR was associated with a longer real-world time to next treatment (HR, 1.96; 95% CI, 1.61-2.38; P =.001) and overall survival (HR, 1.51; 95% CI, 1.19-1.92; P =.001) than BR alone. The team confirmed the efficacy findings in the validation cohort (n=1168).
“In this large cohort of patients treated primarily in the US community setting, only one in four young patients received cytarabine or ASCT consolidation, suggesting the need to develop treatments that can be delivered effectively in routine clinical practice,” wrote the researchers. “Together with the validation cohort, data support future clinical trials exploring regimens without ASCT consolidation in young patients, whereas [maintenance rituximab] should be considered for patients after 1L BR and [R-CHOP].”
Limitations of the study included the retrospective design, missing patient baseline characteristics data, lack of tumor response data, use real-world time to next treatment as a proxy to define patient eligibility for ASCT or maintenance rituximab, non-randomized use of maintenance rituximab or ASCT, lack of documentation of physician intention regarding treatment choices, and residual biases (selection and immortal time bias).
Disclosure: This research was supported by Janssen Research & Development LLC. Please see the original reference for a full list of disclosures.
Martin P, Cohen JB, Wang M, et al. Treatment outcomes and roles of transplantation and maintenance rituximab in patients with previously untreated mantle cell lymphoma: results from large real-world cohorts. J Clin Oncol. Published online June 28, 2022. doi:10.1200/JCO.21.02698