A population-based study of retinoblastoma incidence and survival in Argentine children.

Abstract

An increased incidence of retinoblastoma in some developing countries has been reported but no conclusive data are available from population-based studies at national level. To report the incidence and survival of retinoblastoma in Argentina from the National Pediatric Cancer Registry (ROHA) and the influence of socio-economical indicators on outcome. Cases reported to the ROHA (2000-2009) were analyzed. Incidence rates were calculated using National Vital Statistics and survival was estimated. The extended human development index (EHDI) was used as a socio-economical indicator. With 438 patients reported, an incidence of 5.0 cases per million children 0-14 years old (95% CI 3.5-6.4) was calculated. Median age at diagnosis was significantly higher for children from provinces with lower EHDI; (24 vs. 35 months for unilateral, (P = 0.003) and 9 versus 11.5 months for bilateral retinoblastoma (P = 0.027). The 3-year probability of survival was 0.87 and 0.94 for unilateral and bilateral retinoblastoma, respectively. Residents in provinces with higher EHDI had a better 3-year survival (0.93 vs. 0.77 for lower EHDI, P < 0.0001). Probability of survival was higher for patients treated at tertiary level institutions (P = 0.0015). The combination of low EHDI residence province with no treatment at a tertiary institution was associated with the worst survival outcome. For both, unilateral and bilateral disease, children who died were in average diagnosed at older age. The incidence of retinoblastoma in Argentina is comparable to that of developed countries. Retinoblastoma is diagnosed later and survival is lower in the less developed areas of the country.