Abstract 2530: Incidence trends of childhood and adolescent melanoma in the United States from 1973-2009.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC OBJECTIVE: Melanoma in children and adolescents is rare but, similar to adults, has been reported to be increasing. To gain insight into possible reasons underlying increased number of cases, we analyzed trends in melanoma incidence diagnosed between the ages of 0-19 years among United States whites by sex, stage, age at diagnosis, and primary site. We also investigated incidence trends by ultraviolet B radiation (UVB) exposure levels. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) program data (1973-2009), we calculated age-adjusted incidence rates, annual percent changes, and 95% confidence intervals (CIs) for each category of interest. Incidence trends were also evaluated using joinpoint and loess regression models. SEER registries were categorized with respect to low or high UVB radiation exposure. RESULTS: From 1973-2009, 1,230 children of white race were diagnosed with malignant melanoma. Overall, pediatric melanoma increased by an average of 2% per year (95% CI, 1.4%-2.7%). Females, 15-19 year olds, and individuals with low UVB exposure had significantly higher incidence rates than males, younger children, and those living in SEER registries categorized as high UVB. Over the study period, males experienced increased incidence rates for melanoma on the face and trunk, and females on the lower limbs and hip. The only decreased incidence trend we observed was among 15-19 year olds in the high UVB exposure group from 1985-2009. Loess curves indicated similar patterns. CONCLUSIONS: These results may help elucidate possible risk factors for adolescent melanoma, but further individual-level studies will be necessary to determine the reasons for increasing incidence trends. Citation Format: Jeannette Wong, Jenine Harris, Carlos Rodriguez-Galindo, Kimberly Johnson. Incidence trends of childhood and adolescent melanoma in the United States from 1973-2009. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2530. doi:10.1158/1538-7445.AM2013-2530