Second cancers in long-term survivors of Ewing's sarcoma

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Smith-L-M. Cox-R-S. Donaldson-S-S. Department of Radiation Oncology, Stanford University Medical Center, Clin-Orthop [m. 1992 Jan. (274). P 275-81. Previous reports suggest an increased risk of a second cancer, primarily osteosarcoma, in survivors of Ewing's sarcoma. In a retrospective review of 25 long-term irradiated survivors of Ewing's sarcoma, the incidence of second cancers was determined. The patients were free of disease for more than three years (except for one patient who developed a second cancer 2.5 years after diagnosis), with a median follow-up period of 7.6 years. All received megavoltage radiation to the primary tumor. Twenty-four of the 25 patients were treated with chemotherapy. Second cancers developed in two patients. Acute myelogenous leukemia (AML) developed in a seven-year-old 15 months after treatment. An osteosarcoma developed within an irradiated field in a 13-year-old three years after treatment. The actuarial risk of developing a second cancer at five years is 8% whereas the actuarial risk of developing a bone sarcoma is 4%. Genetic factors [1mmay [m play a role in the development of AML in patients with Ewing's sarcoma. Megavoltage radiation, particularly doses greater than 60 Gy, as well as alkylating agent chemotherapy [1mmay [m contribute to the risk for bone sarcoma. The risk of a second cancer after successful treatment of Ewing's sarcoma is similar to that expected for survivors of all childhood cancers. Author-abstract.