Abstract
BACKGROUND: Retinoblastoma is a rare malignancy involving the retina, although, more common among children, with genetic inheritance explaining the incidence as well as acquired forms. The incidence varies among race and sex as well as mortality and survival. The current study aimed to assess retinoblastoma cumulative incidence (CMI), mortality, and survival by sex. METHODS: A retrospective cohort design was used to assess the CMI, mortality, and survival in this pediatric malignancy based on the Surveillance Epidemiology and End Results (SEER) data 2000-2017. The binomial regression model was used to examine sex differentials in mortality, as well as other study variables, while Cox proportional hazard model was used for the survival variability by sex. RESULTS: The CMI during this period was higher among males relative to females (males n = 249, 56.7%; females n = 190, 43.3%, χ(2) = 2.90, df = 1, p = 0.089). There were sex differences in mortality, with excess mortality observed among males compared to females, risk ratio = 3.40, 95% CI [1.0-15.72]. The survival differences by sex indicated decreased survival among males relative to females, hazard ratio (HR) = 3.39, 95% CI [1.0-15.72]. After controlling for the potential confoundings, namely tumor grade, urbanity, and median income the survival disadvantage of males persisted. Compared to females', males were more than three times as likely to die, adjusted HR = 3.42, 99% CI [0.37-31.60]. CONCLUSION: In a representative sample of pediatric retinoblastoma, there was a sex differential in survival with excess risk of dying identified among males relative to females, which may be explained in part by male X-linkage.