How high can we increase complete remission rate in adult acute myeloid leukemia?

Unequivocally, complete remission (CR) is a prerequisite for the cure for acute leukemia. The history of drug therapy for acute leukemia has taught us that only after CR rates exceed 90% can a satisfactorily high cure rate be obtained, as is observed in acute lymphoblastic leukemia in children and acute promyelocytic leukemia (APL). In multicenter studies of adult acute myeloid leukemia (AML), CR rates hardly exceed 80% with currently available cytotoxic drugs, except for a small fraction of patients having AML with t(8;21) or inv(16). CR rates and survival of adult patients with AML in 4 studies by the Japan Adult Leukemia Study Group from 1987 to 1997 do not improve at all when appropriately adjusted. The remarkable effects of all-trans-retinoic acid in APL and STI571 in chronic myeloid leukemia have shown us the direction of cancer therapy in the 21st century. We should shift the paradigm from nonspecific cytotoxic chemotherapy to therapy that specifically targets the genes or gene products that are responsible for leukemogenesis.