Questionnaire study of cancer etiology in 503 children.

Usefulness of an etiologic questionnaire was examined in an interview study of 503 children with cancer. The medical records of the children were abstracted, and their parents responded to a questionnaire-interview to identify genetic and environmental causes of cancer. Among 1,123 siblings of the index patients, 10 developed cancer as compared with 2 expected on the basis of cancer rates for the general population. Cancer risk factors were identified in individual patients with predisposing genetic and congenital disorders: neurofibromatosis (brain tumor), hereditary immunodeficiency (lymphoma), Down's syndrome (leukemia), XY gonadal dysgenesis (germ cell tumor), giant nevus (melanoma), and meningocele (sacral teratocarcinoma). Environmental causes of childhood cancer were difficult to discern because prior exposures were numerous, diverse, and usually ill defined. The questionnaire yielded more data than the medical record on gestational and family history and helped identify patients with exceptionally high cancer risk for additional investigation. Although the findings provide anecdotal confirmation of several associations, few original etiologic hypotheses were generated for formal testing with conventional epidemiologic techniques.