Increasing incidence of neuroblastoma and potentially higher associated mortality of children from nonmetropolitan areas: analysis of the surveillance, epidemiology, and end results database.

Geographic variations in cancer incidence and mortality can yield clues regarding etiology and healthcare access. We examined pediatric neuroblastoma incidence and mortality in metropolitan counties (containing a core urban area of 50,000 or more people) versus nonmetropolitan counties. We identified cases through the Surveillance, Epidemiology, and End Results database. We analyzed age, race, sex, year of diagnosis, mortality, and county type (metropolitan or nonmetropolitan). In total, 1777 neuroblastoma cases were identified. From 1973 to 2003, the incidence of pediatric neuroblastoma in nonmetropolitan counties has risen from 0.8 to 1.2 cases per 100,000 person-years (annual percent change, 2.09%, P<0.05), whereas the incidence in metropolitan counties remained stable at 1.1 cases per 100,000 person-years over the same interval. The numbers of White children, an at-risk group for neuroblastoma, have increased in nonmetropolitan counties more than in metropolitan counties. Mortality rates were higher in nonmetropolitan versus metropolitan counties [hazard ratio 1.28 (95% confidence interval: 1.02-1.62), log-rank test P=0.0357]. The incidence of pediatric neuroblastoma in nonmetropolitan counties seems to be increasing, possibly due to demographic or environmental factors. Mortality seems to be higher in children from nonmetropolitan versus metropolitan counties. However, this study is limited by sample size. These concerning trends warrant further study through means other than Surveillance, Epidemiology, and End Results.