SYNGENEIC MARROW TRANSPLANTATION IN PATIENTS WITH MULTIPLE-MYELOMA

Eleven patients with advanced multiple myeloma (MM) received syngeneic marrow (It = 10) or peripheral blood stem cell (it = 1) transplants f ollowing cyclophosphamide (CY) and total body irradiation (TBI) (n = 8 ), busulfan (Bu) and CY (It = 1), Bu, CY and TBI (It = 1) or Bu, melph alan and thiotepa (it = 1). At the time of transplant one patient had stage II: and 10 patients had stage III disease. Four patients had ref ractory disease, two had chemotherapy sensitive disease and five had p rogressed after an initial response to chemotherapy. The median time f rom diagnosis to transplant was 353 days (range 176-6118). After trans plant, the median time to achieve granulocytes of 0.5x10(9)/l and plat elets of 20 x 10(9)/l was 12 days (range 9-20) and 12 days (9-27), res pectively. One patient died of interstitial pneumonia syndrome on day 32 and one died of veno-occlusive disease of the liver on day 44 post- transplant, and these were unevaluable for response. Five of nine eval uable patients achieved a complete response (CR), three a partial resp onse, and one patient had no response. Three patients who did not achi eve CR died of progressive disease 106, 142 and 321 days post-transpla nt. Of five patients,who achieved a CR, three relapsed on days 539, 73 7 and 1706 and died on days 1759, 1596 and 1736, respectively; one pat ient died of myelodysplastic syndrome on day 1407 without evidence of MM and one patient is alive and disease-free 3297 days after transplan t. One of the two long-term survivors has a persistent monoclonal prot ein in the blood 15 years post-transplant. These data show that high-d ose therapy and infusion of normal syngeneic marrow cells can cure a s mall fraction of patients with MM. However, the majority of patients d id not achieve durable CR, demonstrating the need for improved transpl ant conditioning regimens, earlier transplant or additional post-trans plant treatment strategies when syngeneic transplants are performed.