Purpose: To compare progression-free survival (PFS), overall survival (OS), and toxicity of a doxorubicin-containing regimen administered alone or in combination with interferon alfa-2b (IFNalpha) in patients with low-grade follicular lymphoma (FL) and poor prognostic factors.
Patients and methods: Two hundred sixty-eight patients with advanced-stage FL received cyclophosphamide, doxorubicin, teniposide, and prednisone (CHVP) monthly for 6 months, then every 2 months for 12 months. After randomization, 242 patients were evaluated for efficacy: 119 received CHVP alone, and 123 also received IFNalpha at a dose of 5 million units three times weekly for 18 months.
Results: After a 6-year median follow-up, the patients treated with CHVP + IFNalpha showed significantly longer median PFS than those who received CHVP alone (2.9 years v 1.5 years, respectively; P = .0002) and significantly longer median OS (not reached v 5.6 years, respectively; P = .008). Although some side effects, which included neutropenia, asthenia, fever, elevated serum transaminase levels, flu-like symptoms, and thrombocytopenia, were more frequently observed in patients who received the combination regimen, these reactions were moderate. IFNalpha was withdrawn because of toxicity in 10% of the patients, and a dosage reduction or temporary suspension was required in 28%.
Conclusion: With long-term follow-up of 6 years, these results confirm that the addition of IFNalpha to a doxorubicin-containing regimen for patients with advanced-stage and clinically aggressive FL not only increased PFS, as in most other similar trials, but also prolonged OS. Toxicity was moderate. The beneficial effects of this combined chemotherapy and IFNalpha regimen on OS probably reflect the selection of FL patients with poor prognostic factors.