Introduction: Metastatic melanoma has an ominous prognosis. Bio-chemotherapy regimens can increase the response rate but with a high degree of toxicity due, mainly, to the use of high-dose intravenous interleukin-2.
Objectives: To test the feasibility and activity profile of a bio-chemotherapy regimen of low-dose subcutaneous interleukin-2.
Material and methods: Administration scheme: dacarbazine at 200 mg/m2/d on days 1-4, cisplatin at 20 mg/m2/d intravenous on days 1-4, vinblastine at 1.5 mg/m2/d on days 1-4, IL-2 at 4.5 MUI/m2/d subcutaneous on days 5-8, IFN-alpha at 5 MU subcutaneous on days 5-9, 11, 13, 15 of every 21-day cycle.
Results: Objective response was obtained in 11 patients (39.3%; 95%CI: 21-59) including 4 with complete response (14.3%; 95%CI: 4-33). With an extended follow-up of 49 months and 60 months, respectively, 2 patients continue with complete response. The main toxicities were haematological: grade 3-4 neutropenia in 8.2% of cycles, thrombocytopenia in 1.2% and anaemia in 3.2%.
Conclusions: The regimen is safe and has a good activity profile. The presence of long-term survivors, despite the use of lower doses and subcutaneous IL-2, is encouraging.