Most stage III melanoma patients do not benefit from treatment with interferon, show final results for the Sunbelt Melanoma Trial. Interferon was approved by the FDA in 1995 as a therapy for melanoma based on a study of patients with multiple large, palpable lymph nodes involved with cancer. However, the development of sentinel lymph node (SLN) biopsy in the 1990s made it possible for physicians to detect microscopic amounts of cancer in lymph nodes that could not be detected by hand.