Single-agent interleukin-2 in the treatment of metastatic melanoma: a systematic review

BACKGROUND: The aim of this systematic review was to determine the role of single-agent interleukin-2 in the treatment of adults with metastatic melanoma. Outcomes of interest include objective and complete response rates, duration of response, toxicity and quality of life. METHODS: A systematic review of the literature was conducted to locate randomized controlled trials, meta-analyses, and systematic reviews published between 1985 and 2006. RESULTS: Data from three randomized controlled trials demonstrate that single-agent interleukin-2, when given in high-doses, elicited objective response rates of 5-27% with complete responses in 0-4% of patients. High-dose interleukin-2, administered as a single-agent or in combination with lymphokine-activated killer cells, demonstrates complete response rates ranging from 0% to 11% and has shown consistent observations of long-term responses that range from 6 to 66+ months (median 27 months). Non-comparative phase II trials of high-dose single-agent interleukin-2 have consistently reported objective response rates of 10-33% with complete response rates ranging from 0% to 15%. Complete responders in those trials also demonstrate long-term responses ranging from 1.5 to 148 months (median 70 months). No other therapy for metastatic melanoma offers the possibility for a durable complete remission. CONCLUSION: This systematic review suggests that patients with a good performance status (ECOG 0-1), a normal lactate dehydrogenase level, less than three organs involved or cutaneous and/or subcutaneous metastases, have the highest probability of responding and achieving a durable complete response. This carefully selected group of patients should be considered for treatment with high-dose interleukin-2.