[2nd malignant tumors in children. Study of 38 cases]

Thirty-eight children, followed in the pediatric Department of Institut Gustave-Roussy, developed second malignant neoplasms. Intervals between the two neoplasms ranged from 1 to 26 years. The second neoplasms were defined as having a different histologic diagnosis than the first ones: osteosarcoma, fibrosarcoma, thyroid carcinoma, leukemia were the most frequent second neoplasms. The potential carcinogenic part of chemotherapy and radiotherapy is emphasized. In addition, some genetic susceptibility may enhance the carcinogenic effects of therapy. Nevertheless the incidence of second malignant neoplasms is low. Its estimation is discussed here.