OUTCOME OF 2ND BONE-MARROW TRANSPLANTATION FOLLOWING A UNIFORM CONDITIONING REGIMEN AS THERAPY FOR MALIGNANT RELAPSE

Twenty-three second bone marrow transplants (BMT) were performed betwe en October 1987 and January 1994 for patients with malignant relapse f ollowing initial BMT. For first BMT, twenty-one of 23 (91%) were condi tioned with cyclophosphamide plus total body irradiation. For second B MT, a uniform conditioning regimen consisting of busulfan and cyclopho sphamide was used. Eleven patients had chronic myelogenous leukemia, s even acute leukemia, four lymphoma, and one myelodysplastic syndrome. Median patient age at second BMT was 32 years, the median time between first BMT and relapse was 22 months, and the median time to second BM T after relapse was 5 months. The second BMT marrow source included: a utologous marrow (1), unrelated donors (4), new matched sibling donors (5) and same matched sibling donors as the first BMT (13). The Kaplan -Meier disease-free survival and survival rates at 3 years were 38 and 43%, respectively (median follow-up of survivors was 45 and 48 months , respectively), and five patients survive disease-free at 46 years. N ine of the 13 deaths occurred within 100 days after second BMT; eight had relapsed within 1 year of the first BMT. We conclude that: (1) sec ond BMT can offer durable long-term survival in certain patients, espe cially those who relapse late after first transplant; (2) busulfan and cyclophosphamide is a suitable conditioning regimen for second BMT.