IL2 and metastatic melanoma: The first publication reporting the efficacy of high-dose (HD) interleukin-2 (IL-2) for patients with metastatic melanoma appeared in 1985; a subsequent manuscript describing 270 patients treated with HD IL-2 reported a complete response (CR) rate of 6% and a partial response (PR) rate of 10% with a median duration of response greater than 40 months.1 2 Over 70% of patients achieving a CR and approximately 15% of those achieving a PR were alive and without recurrence at 15 years identifying HD IL-2 as the first curative immunotherapy regimen for patients with stage IV melanoma.