Purpose: We conducted a randomized prospective trial in selected patients with fully resected high-risk stage I and II malignant melanoma.
Patients and methods: Interferon alfa-2a (IFN-alpha 2a) 20 x 10(6) U/m2 was administered three times each week for 12 weeks by the intramuscular route. Both the treatment group (n = 131) and the control group (n = 131) were evenly balanced with regard to relevant prognostic discriminants.
Results: The median disease-free survival (DFS) time was 2.4 years for the IFN-alpha 2a group and 2.0 years for the observation group (log-rank P = 0.19). The median survival times were 6.6 years for IFN-alpha 2a and 5.0 years for observation (log-rank P = .40). For stage I patients (n = 102), there was no apparent therapeutic advantage from IFN-alpha 2a therapy. The DFS for stage II patients was a median of 10.8 months in the control group versus 17 months in the treatment group. The overall survival time was 4.1 years for the treatment group versus 2.7 years for the control group. The differences in DFS for stage II patient were significant in a Cox model. These results must be interpreted cautiously because of subset analysis. A severe flu-like toxicity occurred in 44% of patients, 13% lost at least 10% of their baseline weight, and 45% experienced a worsening of Eastern Cooperative Oncology Group (ECOG) performance score.
Conclusion: Our findings indicate trends that suggest a possible benefit for selected patients with high-risk malignant melanoma. The results will require further study in a larger patient population for confirmation.