The anti-tumoral activity of interleukin-2 (IL-2) is well-documented. Although the response rate with this cytokine is low, it appears to be improved when associated with interferon-alpha (INF-alpha) and/or cytotoxic drugs. Aim of this work was to study the efficacy and tolerance of an ambulatory treatment using subcutaneous, low-dose IL-2 with subcutaneous INF-alpha and chemotherapy. We report a multicenter study of ambulatory treatment combining subcutaneous (SC) low-dose IL-2 (9 x 10(6) IU) with SC INF-alpha-2a (3 x 10(6) IU) and cisplatin (100 mg/m2) in 33 patients (13 women and 20 men, 22 to 66 years of age) with metastatic malignant melanoma. Metastases were mainly nodal (54.5%) and pulmonary (51.5%). For 81.8% of patients, this therapy constituted the firstline treatment. The overall response rate at the end of the first maintenance course was 30.3% (3 complete responses and 7 partial responses). Adverse effects were observed in 28 patients (84.8%), but were most often minor (grade 1 or 2 on the WHO toxicity scale). The results confirmed the good tolerance to SC IL-2 and its suitability for ambulatory therapy, as well as the potential benefit of associating IL-2 with cisplatin in the treatment of metastatic melanoma (a possibility considered in two previous studies).