Autologous bone marrow transplantation for acute myeloblastic leukemia in Europe: further evidence of the role of marrow purging by mafosfamide. European Co-operative Group for Bone Marrow Transplantation (EBMT).

Fifty-nine European teams have reported 919 autografts for the consolidation of acute myelocytic leukemia (AML) up to December 31, 1989. The distribution for autologous bone marrow transplantation (ABMT) was 671 in first complete remission (CR1) and 196 in CR2. Pretransplantation regimes were: total-body irradiation (TBI), 456; busulfan plus cyclophosphamide (BU-CY) 174; marrow purging with mafosfamide, 269 (corresponding to 26% of all patients in CR1 and 41% in CR2). Patients autografted in CR1 with no high risk factor (standard risk) had a leukemia-free survival (LFS) and relapse rate at 7 years of 48 +/- 2 and 41 +/- 3%, respectively. Of all the prognostic factors studied, only secondary leukemia was correlated with a poorer LFS (19 +/- 9% at 1 year) and a higher relapse rate (76 +/- 11%) (p less than 0.0001). For patients autografted in CR2, the LFS and relapse rate were 34 +/- 4 and 54 +/- 5%. With the restriction of a shorter follow-up, the results achieved with the BU-CY combinations (LFS and relapse rate at 3 years, CR1 47 +/- 6 and 45 +/- 7%; CR2, 37 +/- 9 and 50 +/- 10%) did not differ from those with TBI or other chemotherapy combinations. LFS and relapse rates were correlated with several pretransplant intervals: in CR1, patients reaching CR more rapidly (less than or equal to 40 days) had a better LFS (53 +/- 3 versus 42 +/- 3%; p = 0.03) and a lower relapse rate (46 +/- 3 versus 57 +/- 3%; p = 0.03). In patients autografted less than 3 months, 3-6 months and more than 6 months after CR, the LFS was 26 +/- 5, 49 +/- 3, and 55 +/- 4%, respectively, and the relapse rates 63 +/- 5, 38 +/- 3, and 36 +/- 4% (p less than 0.0001 for both). In CR2, patients autografted more than 18 months after the initial diagnosis had a better LFS (42 +/- 5 versus 24 +/- 5%; p less than 0.001) and a lower relapse rate (45 +/- 6 versus 65 +/- 6%; p less than 0.001). For those autografted less than 3 months, 3-6 months and more than 6 months after CR, the probability of LFS was 30 +/- 5, 30 +/- 7, and 50 +/- 9% (p = 0.06), respectively and the relapse rates 63 +/- 6, 50 +/- 8, and 36 +/- 8% (p = 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)