Subgroup Analyses
Dr. Schultz and his colleagues included 1,480 patients from five studies in a subgroup analysis of overall survival in follicular lymphoma. Of these patients, 97 of 759 (13%) died after treatment with R-chemo vs 142 of 721 (20%) after chemotherapy alone. This indicated significantly better overall survival in the R-chemo group than in the chemotherapy-alone group (HR for mortality = 0.63). "Assuming a 2-year overall survival rate of 90% for patients with follicular lymphoma and the estimated HR of 0.63, the number of patients who would need to be treated with R-chemo to prevent one additional death in 2 years was 28," the authors said.
A subgroup analysis of patients with mantle cell lymphoma included three trials with a total of 260 patients; it showed an overall survival advantage for R-chemo, compared with chemotherapy alone (HR for mortality = 0.60). "However, there was heterogeneity among the trials (P = .07), making the survival benefit less reliable," Dr. Schulz said.
"This meta-analysis demonstrated that in patients with indolent or mantle cell lymphoma, R-chemo is superior to chemotherapy alone with respect to remission, induction, progression-free survival, and overall survival," the authors concluded. One of the most important open questions for patients with indolent non-Hodgkin's lymphoma, they said, is "the impact of maintenance treatment with rituximab on overall survival."
