Long-term data of a phase III study further supported an immunotherapy plus chemotherapy combination regimen as the standard induction strategy for patients with high-risk follicular lymphoma.
Data were published online in the Journal of Clinical Oncology (January 22, 2018; doi:10.1200/JCO.2017.74.5083).
SWOG S0016 was a randomized phase III study that compared the safety and efficacy of R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) with CHOP-RIT (CHOP followed by consolidation with iodine-133-tositumomab radioimmunotherapy) for treatment naïve patients with follicular lymphoma. Recently, long-term follow-up data of this study became mature.
The study enrolled 531 treatment naïve patients with follicular lymphoma from 2001 through 2008. Patients were randomly assigned to receive either six cycles of R-CHOP or six cycles of CHOP-RIT. Eligibility criteria included advanced-stage disease of any pathologic grade.
After a median follow-up of 10.3 years, 10-year progression-free survival (PFS) and overall survival (OS) were 49% and 78%, respectively, among all patients. Those in the CHOP-RIT arm benefited from significantly better 10-year PFS compared with those in the R-CHOP arm (56% vs 42%, respectively; P = .01). However, 10-year OS was comparable between the two treatment arms (75% vs 81%, respectively; P = .13).
Researchers reported no significant differences between the two treatment arms in regard to incidence of second malignancies (15.1% vs 16.1%; P = .81), or myelodysplastic syndrome or acute myeloid leukemia (4.9% vs 1.8%; P = .058). Estimated 10-year cumulative incidences of death resulting from second malignancies were similar (7.1% vs 3.2%; P = .16), but cumulative incidence of death resulting from myelodysplastic syndrome or acute myeloid leukemia was higher in the CHOP-RIT arm compared with the R-CHOP arm (4.0% vs 0.9%; P = .02).
Authors of the study concluded that, “Given these outstanding outcomes, immunochemotherapy should remain the standard induction approach for patients with high-risk follicular lymphoma until long-term follow-up of alternative approaches demonstrates superiority.”—Zachary Bessette