AUTOLOGOUS OR ALLOGENEIC BONE-MARROW TRANSPLANTATION FOR ACUTE MYELOBLASTIC-LEUKEMIA IN 2ND COMPLETE REMISSION - IMPORTANCE OF DURATION OF FIRST COMPLETE REMISSION IN FINAL OUTCOME

Between May 1983 and March 1994, 31 patients with AML in second CR und erwent BMT. Fifteen underwent allogeneic BMT from an HLA-identical sib ling donor and 16 without a donor, unpurged ABMT. Two different prepar ative regimens were used: CY (120 mg/kg) and 12 Gy of fractioned TBI ( 19 patients), and Bu (16 mg/kg) and Cy (120 mg/kg) (BuCy2) in 12 patie nts. Main clinical characteristics including age, sex, length of first remission, FAB type, and number of leukocytes at diagnosis were simil ar in both groups. A combination of MTX and CsA was used in 13 cases w hereas either CsA or MTX alone was employed in the other two patients. With a median follow-up of 5 years the actuarial 5 year probability o f disease-free survival (DFS) for the whole group was 39.8% (95% CI: 2 9.5-50.1%). The 5 year DFS was equivalent for those who received eithe r ABMT (41.6 +/- 14.2%) or allogeneic BMT (40 +/- 15%). Probabilities of relapse and non-relapse mortality for ABMT and allo BMT patients we re 48.7 +/- 16.1 and 18.7 +/- 14.3, and 30.1 +/- 19.2 and 40.7 +/- 16. 9, respectively. DFS was better in those patients with a longer durati on of first CR (>18 months) 62.5 +/- 14.4 vs 30.4 +/- 17.9%, attributa ble to a significantly lower relapse rate in this group of patients 16 .6 +/- 12.8 vs 57.8 +/- 22.7 (P 0.05). In conclusion, similar results were observed when ABMT and allo BMT were compared for AML in CR2. A h igher antileukemic effect associated with the allo BMT is balanced by an increase in transplant-related mortality. Duration of first remissi on was the most important factor affecting DFS and better outcome was observed for patients with longer CR1.