Acute leukemia as a delayed consequence of cancer chemotherapy.

Acute myelocytic leukemia occurring many years after intensive radiotherapy and/or chemotherapy has been reported in 82 patients with Hodgkin's disease, 58 patients with multiple myeloma, and 40 patients with chronic lymphocytic leukemia. The precise incidence of this occurrence is uncertain, since the total number of patients at risk is unknown. Most patients with Hodgkin's disease had received intensive radiation therapy. Many also received chemotherapy. One-third of the patients with myeloma were treated only with melphalan. Acute leukemia may occur as part of the natural history of Hodgkin's disease and multiple myeloma; it has been seen with increasing frequency in recent years due to improved survival secondary to better treatment. It is also possible that radiotherapy and/or chemotherapy may be causally related to the development of acute leukemia.