THE INFLUENCE OF SUBSEQUENT NEOPLASMS ON INCIDENCE TRENDS IN CHILDHOOD-CANCER

The purpose of this analysis was to evaluate to what extent subsequent malignant neoplasms account for the increasing rates of cancer occurr ence among children. Data from the population-based Surveillance, Epid emiology, and End Results program were used to calculate age-standardi zed annual incidence rates from 1974-1989 for 10 common cancers among children 14 years of age or younger. Mean rates and linear trends were evaluated using least squares regression, first for all neoplasms and then excluding subsequent neoplasms, to determine if the removal, of subsequent neoplasms would attenuate increasing trends. Increasing ann ual incidence rates were found for all childhood cancers combined, acu te lymphoid leukemia, and brain tumors, but not for other cancer types . Excluding subsequent neoplasms from the analysis had a negligible ef fect on the trends we observed. Although it remains largely undetermin ed why childhood cancer incidence rates are increasing in the United S tates, this study presents evidence that subsequent primary neoplasms do not substantively contribute to these observed trends.