Modified Tumor Infiltrating Lymphocytes for Metastatic Melanoma

Background: \- Tumor infiltrating lymphocytes (TIL) are white blood cells that have been taken from tumor tissue. The cells are modified to help them kill tumor cells, then given back to the person with cancer. By giving these cells to patients, researchers hope to improve the current treatments available for patients with melanoma that has not responded to standard therapies. The TIL will be given after treatments that will suppress the immune system. This makes it easier for the TIL to attack the cancer cells. The TIL will also be given with aldesleukin (IL-2), which is designed to help keep the TIL cells alive in the body. Objectives: \- To study the safety and effectiveness of specially modified tumor infiltrating lymphocytes to treat melanoma that has not responded to other treatments. Eligibility: \- Individuals at least 18 years of age who have metastatic melanoma that has not responded to other treatments. Design: * Participants will be screened with a physical exam and medical history. They will also have blood tests and imaging studies. * A piece of tumor will be collected and white blood cells will be separated to make the TIL for the treatment. * Participants will take drugs to suppress the immune system for 7 days before the start of treatment. * Participants will receive the TIL in a single dose. Then they will receive IL-2 every 8 hours for up to 15 doses. Participants will remain in the hospital for up to 2 weeks after treatment. They will be monitored with frequent blood tests and other studies. * After leaving the hospital, participants will have regular followup visits every 1 to 4 months for the first year. Then they will return for followup every 3 to 4 months, as directed by the study researchers.