Secondary tumors in bone sarcomas after treatment with chemotherapy

New oncologic treatments have improved survival in osteosarcoma and Ewing's sarcoma. However, these treatments may cause secondary malignancies after radiotherapy. This study evaluated the incidence of secondary malignancies after neoadjuvant chemotherapy. Between April 1972 and December 1990, 518 o steosarcoma and 299 Ewing's sarcoma patients entered neoadjuvant chemothera py protocols. Follow-up records of all patients were analyzed and malignant tumors were reported. Nine patients developed another malignancy, includin g 5 leukemias, 1 astrocytoma, 1 liposarcoma, 1 parotid, and 1 breast carcin oma. Four leukemias were found in patients treated for osteosarcoma with ch emotherapy, but not radiotherapy. Only one leukemia developed after Ewing's sarcoma treated with chemotherapy and radiotherapy. The incidence of leuke mias is high, while the other tumors can be explained as unrelated cases. I ncidence densities for leukemia were calculated for both groups of patients . Treated osteosarcoma patients seem to have a predisposition to develop le ukemias, but whether this is chemotherapy induced needs to be investigated.