Incidence of retinoblastoma in the USA: 1975-2004

Background: The purpose of this study was to determine the age-adjusted incidence of retinoblastoma in the USA over a 30-year period from 1975 to 2004 using a review of existing databases. Methods: Six hundred and fifty-eight patients with retinoblastoma (International Classification of Oncology (ICDO-3) codes C69.2 (retina) and C69.9 (eye, NOS)) were derived from the Surveillance, Epidemiology, and End Results (SEER) program database in the USA from 1975 to 2004. Nine historical SEER registries were utilised. The significance of trend in age-adjusted incidence rate was determined using the chi(2) test, and 95% CIs were calculated. The patients were stratified according to age at diagnosis, laterality, gender and race. Results: There were a total of 658 cases of retinoblastoma, representing 6.1% of all childhood cancers under age 5 years. The mean age-adjusted incidence of retinoblastoma in the USA was 11.8 per million children aged 0-4 years (95% CI 10.9 to 12.8). There was no significant trend in age-adjusted incidence for all races/genders, nor was there any significant variation of incidence between races or between genders. The proportion of bilateral cases (26.7%) versus unilateral cases (71.9%) remained stable over the 30-year period. Conclusions: The mean age-adjusted incidence rate of retinoblastoma of 11.8 cases per million children aged 0 4 years in the USA is similar to rates reported from European countries. The age-adjusted incidence rate of retinoblastoma in the USA has remained stable for the last 30 years.