OBJECTIVES: I. Determine the response rate and failure-free survival in patients with metastatic cancer (preferably melanoma or renal cell) treated with autologous tumor infiltrating lymphocytes (TIL), interferon alfa (IFN-A), and interleukin-2 (IL-2). II. Describe the toxic effects and costs associated with this therapy to assess risk benefit and cost benefit. III. Assess the relative value of administering low- or high-dose TIL, as well as the value of administering IFN-A before TIL, IL-2 with TIL, or cimetidine with TIL.