High-dose chemoradiotherapy and allogenic bone marrow transplantation in multiple myeloma.

17 patients with multiple myeloma (MM) received marrow transplants from their HLA-matched, MLC-negative sibling donors. 9 patients had progressive disease not responding to conventional treatments, while the other 8 patients were rated as responders. The most frequently used conditioning regimen consisted of total body irradiation and high-dose, multi-agent chemotherapy with cyclophosphamide plus either oral melphalan (5 cases) or BCNU (1 case) on both these drugs (7 cases). 12 patients were evaluable for response to BTM: 7 of them (6 responders and 1 with advanced refractory MM) entered complete remission, while 5 had a sustained decrease in tumor mass that ranged between 72% and 93%. 11 patients died of transplant-related causes, 1 of them with signs of progressive disease. The remaining 6 patients are alive and 5 of them maintain a complete remission status 4 to 67 (median 36) months after BMT. It is concluded that therapeutic benefits of transplantation in MM are still offset by the high mortality related to the procedure. A more accurate selection of patients who would most benefit from BMT and performing transplant at an earlier phase of the disease are warranted before major advances can be made in the cure of these patients.