Low-Intensity Stem Cell Transplantation With Multiple Lymphocyte Infusions to Treat Advanced Kidney Cancer

Background: Low-dose chemotherapy is easier for the body to tolerate than typical high-dose chemotherapy and involves a shorter period of complete immune suppression. Donor immune cells called lymphocytes, or T cells, fight residual tumor cells that might have remained in the recipients body after stem cell transplant, in what is called a graft-versus-tumor (GVT) effect. The immune-suppressing drug sirolimus appears to help prevent graft-versus-host disease (GVHD), a side effect of stem cell transplant in which donated T cells sometimes attack healthy tissues, damaging organs such as the liver, intestines and skin. Th2 cells are cells collected from the transplant donor and grown in a high concentration of sirolimus. Objectives: To determine whether stem cell transplantation using low-dose chemotherapy and sirolimus-generated Th2 cells can cause a remission of advanced kidney cancer. Eligibility: Patients between 18 and 75 years of age who have kidney cancer that has spread beyond the kidney and who have a tissue-matched sibling stem cell donor. Design: Patients undergo stem cell transplantation as follows: * Low-intensity chemotherapy with pentostatin and cyclophosphamide over a 21-day period to reduce the level of the immune system to prepare for the transplant. Pentostatin is given through a vein (intravenous (IV)) on days 1, 8 and 15; cyclophosphamide tablets are taken by mouth for 21 consecutive days. * Sirolimus tablets, taken by mouth, starting 2 days before the transplant and continuing until 60 days after the transplant. * IV infusions of stem cells and Th2 cells. Following the transplant, patients have the following procedures: * Additional Th2 cell infusions on days 14 and 45 after the transplant. * Follow-up visits at the National Institutes of Health (NIH) Clinical Center twice a week for the first 6 months after the transplant and then less frequently for at least 5 years to evaluate response to treatment and treatment side effects. Evalua