Background: Alpha interferon (IFN) is an effective single agent for patients with low-grade lymphoma, but until 1982 had not been integrated with standard chemotherapy for these patients. Since relapse from complete remission (CR) is the rule for patients with advanced stage low-grade lymphoma, a maintenance IFN schedule was explored for patients in CR.
Patients and methods: From 1982-1987, 127 patients with stage IV low-grade lymphoma were treated with cyclophosphamide, doxorubicin, vincristine, prednisone, and bleomycin (CHOP-Bleo) for 9-18 mo. (median 13 mo.), followed by interferon alfa-n-1 (Wellferon) maintenance therapy for 24 mo. for CRs.
Results: The overall response rate for the entire treatment program was 73% CR and 23% partial remission. The median follow up was 59 months. At 5 years, survival was 74%, failure-free survival (FFS) 47%, and FFS of CRs 60%. Compared to a group of 96 patients with similar pretreatment clinical features treated with CHOP-Bleo from 1972-1982, this represents a significant improvement for both overall FFS (p = 0.01) and FFS of CRs (P < 0.01). Toxicity from the IFN maintenance was generally acceptable, but even at the modest dose employed in this trial (3 x 10(6) U/m2 three times weekly), dose modification was required in more than 30% of patients, usually because of fatigue.
Conclusions: The integration of IFN and conventional chemotherapy is feasible and effective. Maintenance IFN prolongs remission duration for patients with stage IV low-grade lymphoma.