125 ADULT PATIENTS WITH PRIMARY ACUTE-LEUKEMIA AUTOGRAFTED WITH MARROW PURGED BY MAFOSFAMIDE - A 10-YEAR SINGLE INSTITUTION EXPERIENCE

A total of 125 acute leukemia adult patients were autografted with bone marrow (BM) purged by mafosfamide (ASTA Z) during the period of January 1983 to January 1993. The median follow-up period was 64 months (range, 3 to 126). There were 84 acute myeloblastic leukemias (AMLs) and 41 acute lymphoblastic leukemias (ALLs). At time of autologous BM transplantation (ABMT); 64 AMLs were in first complete remission (CR1), and 20 were in second CR (CR2); 35 ALL were in CR1, and 6 were in CR2. The median age of the patients was 33 years (range, 16 to 55). The median interval between achieving CR and autografting was 5 months (range, 1.3 to 23). The pretransplant regimen consisted of cyclophosphamide (120 mg/kg) and total body irradiation. All patients were grafted with autologous BM treated in vitro with mafosfamide used at levels individually adjusted in 95 patients and at a standard dose in 30 patients. The initial richness in granulomacrophagic progenitors (CFU-GM) of the harvested BMs was 5.16 x 10(4) CFU-GM/kg (range, 0.55 to 33). After mafosfamide purging, the residual CFU-GM number was 0.021 x 10(4)/kg (range, 0 to 1.78). The probability of successful engraftment was significantly higher and the time to engraftment was significantly shorter in ALL, Of 33 patients grafted with BM containing no residual CFU-GM, those with AML (n = 22) had platelet recoveries that were significantly longer than those for AML patients receiving BM with residual CFU-GM. At 8 years, patients autografted in CR1 for AML and ALL had a leukemia-free survival (LFS) of 58% and 56%, respectively, with a relapse incidence (RI) of 25% and 37%, respectively. Patients autografted in CR2 for AML had an LFS of 34% and an RI of 48% at 5 years. The incidence of late relapses was significantly higher in ALLs. By multivariate analysis, four factors were found to influence favorably engraftment in addition to a diagnosis of ALL, a younger age, ABMT performed in CR1, the adjusted dose technique of purging, and a shorter interval from CR to ABMT. Two factors were correlated with a better outcome. (1) The LFS was significantly higher and the transplant-related mortality significantly lower in patients who received richer BM. (2) The RI was significantly lower in patients autografted within 150 days from CR. Our results reinforce the view that ABMT is one approach to improve the outcome of adult patients with acute leukemia. The initial richness of the BM at collection and the timing of the transplant are important predictive factors for the outcome. (C) 1994 by The American Society of Hematology.