Ethnic, racial and socioeconomic disparities appear to exist among children with retinoblastoma, a once uniformly fatal but now treatable eye cancer, and those disparities are associated with greater risks for advanced disease and undergoing enucleation (removal of the eye), according to an article published online by JAMA Pediatrics.

Retinoblastoma is a rare childhood cancer with about 9,000 cases diagnosed yearly worldwide. When diagnosed early, salvaging the eye and preserving vision are possible with relatively minimal therapy. Although disparities in access to health care have been well discussed for adult cancers, little is known about pediatric cancers.

Carlos Rodriguez-Galindo, M.D., of the Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, and coauthors reviewed 18 Surveillance, Epidemiology and End Results (SEER) registries from 2000 through 2010. The authors identified 830 cases of retinoblastoma for children up to 9 years old and examined the effects of socioeconomic status, race and ethnicity on the extent of disease and outcomes.

Among the 830 children, Hispanic children had a higher percentage of extraocular (outside of the eye or advanced disease) compared with non-Hispanic children 33 percent (86 of 261) vs. 20 percent (102 of 510). Among 771 children whose extent of disease could be determined, 188 (24.4 percent) of them presented with extraocular disease. The percentage of extraocular cases was higher in counties with low socioeconomic status indicators including higher poverty, lower educational attainment, higher levels of crowding, higher unemployment, higher language isolation and higher percentage of immigrants, according to the results.

Ocular outcomes were known for 822 children and 574 of these children (69.8 percent) underwent enucleation at some point in treatment. Hispanic children were 41 percent more likely to undergo enucleation than non-Hispanic white children, according to the study. The percentage of enucleation was higher among Hispanic compared with non-Hispanic children 74.5 percent (202 of 271) vs. 67.5 percent (372 of 551). Higher rates of enucleation also were associated with low educational attainment and a higher level of crowding.

The five-year relative survival rate was 97.7 percent.

The authors acknowledge limitations inherent to the use of SEER registry and census data and to extrapolating indicators to investigate social determinants of health in this specific population.

"Low socioeconomic status affects disease extent and ocular outcomes, presumably by limiting access to primary and cancer-directed care," the study notes.