INV(16) MAY BE ONE OF THE ONLY FAVORABLE FACTORS IN ACUTE MYELOID-LEUKEMIA - A REPORT ON 19 CASES WITH PROLONGED FOLLOW-UP

We report our experience of treatment of acute myeloid leukemia (AML) with inv(ls). Nineteen of 531 (3.6%) cases of newly diagnosed AML kary otyped over a 12 year period had inv(16)(p13q22) and none had t(16;16) or del 16q. Morphologically, all patients had M(4eo). All patients we re treated with conventional anthracycline-Ara-C chemotherapy, followe d by moderate or more intensive consolidation chemotherapy. All patien ts received central nervous system (CNS) prophylaxis with intrathecal methotrexate and Ara-C, and cranial irradiation. Eighteen patients (95 %) achieved complete remission (CR). Three had a bone marrow relapse, one had a CNS relapse and 14 patients remained in first CR, 11 of them with a follow-up greater than 44 months. Disease-free survival was 74 % after 10 months, and actuarial survival 88% after 4 years, and 62% a fter 6 years. No other AML subgroup, in our experience, had a long-ter m survival approaching that of AML with inv(16) (although similar favo rable outcome may be anticipated in acute promyelocytic leukemia treat ed by a combination of retinoic acid and chemotherapy).