Phase III of Study of R-CHOP-21 vs R-CHOP-14 for Untreated Stage III and IV B-cell Non-Hodgkin's Lymphoma: a Report from Iran

Background: A combination of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is one of the most effective front-line therapies to treat B-cell non-Hodgkin's lymphoma (NHL). The aim of this trial was to evaluate overall survival (OS), progression free survival (PFS) and toxicity of R-CHOP-14 compared to R-CHOP-21 in untreated stage III and IV B-cell NHL patients with Iranian ethnicity. Materials and Methods: In a phase III trial, patients with previously untreated stage III and IV indolent and aggressive B-cell NHL were randomly assigned by using a minimization method to receive six to eight cycles of either R-CHOP-21 (administered every 21 days) or R-CHOP-14 (administered every 14 days with granulocyte colony-stimulating factor). Results: A total of 143 patients were randomly enrolled in our study (66 patients in R-CHOP-14 group and 77 patients in R-CHOP-21), between 2011 and 2014. The mean follow-up was 45 months at the time of treatment analysis. The 2-year and 5-year PFS rates for the R-CHOP-14 group were 83.6% vs 73.6% and for R-CHOP-21 group were 75% vs 54%. The 2-year and 5-year OS rates for R-CHOP-14 group were 98% vs 89% and for R-CHOP-21 group were 84.4% vs 67.5%. There was a significant correlation for PFS and OS in the two arms. There was no significant difference between adverse events with the two regimens. Conclusions: In our research improved survival was found with CHOP-14 as compared to CHOP-21. It is possible that drug metabolism in different races/ethnicities may be one important factor.