Second malignant tumors following treatment during childhood and adolescence for cancer

Many pediatric and adolescent cancer patients are treated with carcinogenic chemotherapeutic agents and radiation therapy to achieve permanent control of their malignancy. These modalities may induce a new cancer in the successfully treated patient. To identify disease and treatment factors which increased the risk of occurrence of a second malignant tumor following modern treatment for cancer during childhood or adolescence, we reviewed the courses of 1,406 previously untreated patients who were less than 20 years of age at diagnosis and were treated at Roswell Park Cancer Institute between January 1, 1960 and December 31, 1989. Eighteen patients developed a second malignant tumor, including two meningiomas, 2.65-25.65 years after diagnosis of the first cancer. The actuarial risk of a second malignant tumor was 5.6% at 25 years after diagnosis. Using Cox proportional hazards modelling, we identified prior therapy with BCNU (P = 0.0055) and doxorubicin (P = 0.0254) as the only factors that were significantly associated with the risk of a second malignant tumor. Three second malignant tumors of the central nervous system occurred following treatment with a nitrosourea. Successfully treated patients must be carefully followed to identify treatment related malignant tumors at an early stage.