Geographic and temporal trends in pediatric and young adult brain tumors in Kentucky, 1995-2019.

INTRODUCTION: Pediatric and young adult brain tumors (PYBT) account for a large share of cancer-related morbidity and mortality among children in the United States, but their etiology is not well understood. Previous research suggests the Appalachian region of Kentucky has high rates of PYBT. This study explored PYBT incidence over 25 years in Kentucky to identify geographic and temporal trends and generate hypotheses for future research. METHODS: The Kentucky Cancer Registry contributed data on all PYBT diagnosed among those aged 0-29 during years 1995-2019. Age- and sex-adjusted spatio-temporal scan statistics-one for each type of PYBT, and one for all types-comprised the primary analysis. These results were mapped along with environmental and occupational data. RESULTS: Findings indicated that north-central Kentucky and the Appalachian region experienced higher rates of some PYBT. High rates of astrocytomas were clustered in a north-south strip of central Kentucky toward the end of the study period, while high rates of other specified types of intracranial and intraspinal neoplasms were significantly clustered in eastern Kentucky. The area where these clusters overlapped, in north-central Kentucky, had significantly higher rates of PYBT generally. DISCUSSION: This study demonstrates north-central Kentucky and the Appalachian region experienced higher PYBT risk than the rest of the state. These regions are home to some of Kentucky's signature industries, which should be examined in further research. Future population-based and individual-level studies of genetic factors are needed to explore how the occupations of parents, as well as prenatal and childhood exposures to pesticides and air pollutants, impact PYBT incidence.