A follow-up analysis of the phase III randomized SWOG S0016 study showed that immunochemotherapy should remain the standard induction approach for patients with high-risk follicular lymphoma, according to Mazyar Shadman, MD, MPH, of the Fred Hutchinson Cancer Research Center in Seattle, and colleagues.
These findings were published in the Journal of Clinical Oncology.
A total of 531 previously untreated patients with intermediate- or high-risk, advanced-stage (stage II to IV) follicular lymphoma were enrolled in the study between 2001 and 2008 and randomly assigned to receive 6 cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; n = 267) or 6 cycles of CHOP followed by consolidation with 131I-tositumomab radioimmunotherapy (CHOP-RIT; n = 264).
At a median follow-up of 10.3 years, 10-year rates of progression-free and overall survival were 49% and 78% among all patients, respectively. The 10-year rates of progression-free survival were better in the CHOP-RIT arm (56% vs 42% for patients in the R-CHOP arm; P = .01). But the difference between the 10-year overall survival rates (81% for R-CHOP vs 75% for CHOP-RIT) was not statistically significant.
Patients in both study arms experienced similar rates of secondary cancers (16% vs 15% for R-CHOP and CHOP-RIT, respectively), including hematologic, gastrointestinal, genitourinary, gynecologic, lung, breast, head and neck, thyroid, and skin cancer.
A numerically higher rate of myelodysplastic syndrome and acute myeloid leukemia (4.9% vs 1.8%) in the CHOP-RIT arm fell just short of statistical significance (P = .058). But the estimated 10-year cumulative incidence of death from myelodysplastic syndrome or acute myeloid leukemia was significantly higher for patients in the CHOP-RIT arm compared with the R-CHOP arm (4% vs 0.9%; P = .02), despite the small number of patients in question, consistent with previously reported findings among patients with indolent non-Hodgkin lymphoma, the authors noted.
In the future, new noncytotoxic therapies could change the treatment options for patients with advanced follicular lymphoma. But for the time-being, immunochemotherapy should remain the standard of care for induction therapy, Shadman concluded.