Multiple myeloma terminating in acute leukemia. Report of 12 cases and review of the literature

Twelve cases of multiple myeloma and acute leukemia are reported and an additional 46 cases from the literature are reviewed. In 11 instances, both diseases occurred simultaneously; in 1 case, the diagnosis of acute leukemia cannot be substantiated. In all the remaining 46 patients with multiple myeloma, acute myeloblastic or myelomonocytic leukemia, or a variant thereof, developed. There were no cases of lymphoblastlc leukemia. In 6 cases, no sex was indicated; in the remaining 40, 26 were men and 14 women. Nineteen patients received melphalan therapy only for 22 to 102 months, seemingly implicating this drug in the development of acute leukemia 36 to 147 months later. Twenty-five patients received melphalan as well as other cytotoxic and/or irradiation treatment. Three patients received no melphalan at all. Acute leukemia may be part of the natural history of multiple myeloma and may be seen with increasing frequency because of the longer survival of patients with multiple myeloma since the introduction of melphalan. Late death from acute leukemia after a definite remission, often lasting years, from multiple myeloma is thought to be preferable to early death without remission.