Patients who have previously been vaccinated with Melan-A/MART-1 peptide are eligible. Whole PBMC's containing Melan-A specific CD8+ lymphocytes are collected via lymphocytapheresis and freezed. Lymphodepleting chemotherapy consists of 2 days of Busulfan 2mg/kg at days -7,-6, followed by Fludarabine 30mg/m2 at days -5,-4,-3. At day 0, whole untreated PBMC's are reinfused to the patient and vaccination with Melan-A analog peptide is restarted and repeated every 4 weeks. Immunomonitoring with detailed FACS analysis using tetramers is performed at day 0,8,15,30, and then monthly. The aim is to boost Melan-A specific CD8 T cells in vivo during homeostatic proliferation after lymphodepletion and antigen driven proliferation due to peptide vaccination.