Disease stabilization by leukocyte alpha interferon and survival of patients with metastatic melanoma

Thirty-one patients, 13 males and 18 females, with metastatic malignant melanoma were treated with human leukocyte interferon (IFN) alpha. The dose was 3 x 10(6) IU daily s.c. for 6 weeks followed by 6 x 10(6) IU/day 3 times a week. Only 1 patient (3%) achieved a partial response (PR) while 14 patients (45%) had disease stabilization for 2-8 months. Three patients experienced mixed responses, where some of the metastases responded, while the others were only stabilized. Interestingly, 1 patient showed regression of lung and disappearance of liver metastases after termination of IFN treatment. Two female patients are still alive without evidence of disease. After IFN they were treated with radiotherapy or surgery. The median survival for all the patients was 48 weeks. Our conclusion is that in IFN therapy long-term follow-up is indicated even in the absence of objective responses. In spite of poor response rate IFN may contribute beneficially to survival in a proportion of patients.