Chemotherapy Plus Peripheral Stem Cell Transplantation in Treating Patients With Melanoma or Metastatic Kidney Cancer

OBJECTIVES: * Evaluate the safety of nonmyeloablative chemotherapy followed by allogeneic peripheral blood stem cell transplantation in patients with metastatic renal cell carcinoma or melanoma. * Determine the incidence and severity of all adverse events related to this treatment regimen in this patient population. * Determine the efficacy of this treatment regimen in terms of tumor regression, response duration, progression free survival, and overall survival in these patients. * Measure the resulting chimerism and immune reconstitution in these patients after this treatment regimen and correlate with clinical response. OUTLINE: Patients receive fludarabine IV over 30 minutes on days -8 through -4 and cyclophosphamide IV over 1 hour on days -3 and -2. Immediately following each daily donor leukapheresis, patients receive allogeneic peripheral blood stem cells (PBSC) IV over 15 minutes beginning on day 0 and continuing until the target cells are collected. Patients receive filgrastim (G-CSF) subcutaneously beginning on day 5 and continuing until blood counts recover. If no graft versus host disease has developed within 4 weeks of allogeneic PBSC transplantation, patients with disease progression or recurrence who have residual donor hematopoiesis on chimerism analysis may receive donor T lymphocytes IV over 30 minutes. Patients may receive an additional course of donor T lymphocytes at the investigator's discretion. Patients are followed at days 30 and 100, and then every 3 months thereafter. PROJECTED ACCRUAL: A total of 10-38 patients will be accrued for this study within 2.5 years.