Acute myelocytic leukemia in adults

Abstract

The proposed reasons why acute myelocytic leukemia (AML) is less responsive to chemotherapy than lymphoblastic leukemia are examined. It is concluded that neither difference in age incidence nor difference in pathogenesis provides adequate explanations and that the major reasons why chemotherapy is less successful in AML are because: 1. None of the available cytotoxic drugs is sufficiently selective in killing leukemic myeloblasts and thus remission induction is very hazardous, and 2. There are relatively few drugs available which are dependably lethal to leukemic myeloblasts, thereby hindering effective remission consolidation. Despite these obstacles, several regimens employing combinations of drugs have recently been reported which give remission rates of 50% or better and significant prolongation of survival. The current status of one of these regimens—the “L-6” protocol —is reviewed and discussed in relation to anticipated future developments.