Chemotherapy Plus Interferon- α 2b Versus Chemotherapy in the Treatment of Follicular Lymphoma

Abstract

The best treatment of follicular lymphoma remains to be determined because the long natural history of follicular lymphoma requires mature data for accurate analysis. Although the goal of primary treatment remains durable remission, the sequential application of effective treatments may also result in a prolongation of median survival time. The use of interferon (IFN) with doxorubicin-based chemotherapy has demonstrated an increase of event-free survival but not in overall survival; however, its acute and late cardiac toxicity limits its use. For this reason, we began a controlled clinical trial to assess the efficacy and toxicity of chemotherapy: COPP (cyclophosphamide, vincristine, prednisone, and procarbazine) + IFN alternating every month for six cycles compared to six cycles of chemotherapy. In an intent-to treat analysis, 55 patients were enrolled (median age 61 years). Most cases (91%) with advanced disease were randomly assigned to chemotherapy + IFN (28 cases) or chemotherapy (27 cases). Complete remission was observed in 16 patients: 59% (95% CI, 53-70%) in the chemotherapy arm compared to 20 patients 71% (95% CI, 58-79%) in the chemotherapy + IFN arm; total responses were 74% and 86%, respectively. At a median follow-up of 60 months, event-free survival was 100% for patients treated with chemotherapy + IFN, which was statistically different from patients treated with chemotherapy 70%. At 7 years, median survival has not yet been reached; 72% of patients chemotherapy + IFN remain alive without disease (95% CI, 59-81%), which is not statistically different from 72% (95%CI, 50-73%) in the chemotherapy arm. Non-hematological toxicity was most frequent and severe in the chemotherapy arm; hematological toxicity was similar in both groups. Thus, it appears that chemotherapy + IFN, as described herein, improves event-free survival but the overall survival rates remain unchanged. The use of COPP appears to be better that anthracycline-based chemotherapy because it avoids the presence of acute and late cardiac toxicity.