The contribution of nonmalignant tumors to CNS tumor incidence rates among children in the United States

Objectives: According the U.S. National Cancer Institute (NCI), the incidence rate of primary malignant central nervous system (CNS) neoplasms among children is about 30 per million person-years. This rate, however, underestimates the true burden of CNS tumors because nonmalignancies are not included in the NCI case reporting system. Intracranial tumors, to an extent regardless of their histological behavior, can have a malignant clinical course and result in a high degree of morbidity and mortality. The purpose of this report is to estimate the contribution that nonmalignant tumors have on the overall incidence of CNS tumors in children. Methods: Population-based data from the Central Brain Tumor Registry of the United States were analyzed. Included in the analysis were children aged 0-19 years who were diagnosed with a primary CNS tumor from 1990-93 (N = 1133). Results: The inclusion of nonmalignancies increased the CNS tumor incidence rate by 28% from 29.4 to 37.6 per million person-years. The increases were 17% for children aged 0-4 years, 17% for children aged 5-9 years, 31% for children aged 10-14 years and 57% for adolescents aged 15-19 years. Differences in patterns between malignant and nonmalignant tumor occurrence by sex, histology, and location were also observed. Conclusion: Because of the potentially profound adverse health effects on children who experience CNS tumors, the systematic collection of both malignancies and nonmalignancies is consistent with the mission of public health surveillance. Without such population-based data, analytic epidemiologic studies to evaluate disease etiology and assess disease consequences are greatly hindered.