AT WHAT AGE COULD SCREENING FOR FAMILIAL RETINOBLASTOMA BE STOPPED? REVISED DUTCH RETROSPECTIVE POPULATION BASED COHORT STUDY 1991-2019.

Objective: To determine the latest age at which familial retinoblastoma (Rb) is diagnosed in children screened from birth and to assess the implications for optimizing screening protocols.

Study design: Retrospective cohort study utilizing nationwide data from the Dutch Rb registry, covering diagnoses from 1991 to 2019.

Subjects: The study included 38 children with familial Rb, 28 of whom were completely screened from birth according to a standardized protocol, and 10 were considered incompletely screened.

Methods: Data on genetic testing, screening methods, timing, and age at diagnosis were extracted from medical records at Amsterdam UMC.

Main outcome measures: Age at diagnosis of familial Rb, categorized by complete versus incomplete screening status.

Results: All 28 completely screened children were diagnosed before one year of age, with a median age at diagnosis of 18 days (range: 3-352 days). Sixteen (57.1%) were diagnosed at their first examination within the first month after birth, and 82.1% were diagnosed within the first six months. Among 10 incompletely screened children, the median age at diagnosis was 420 days (range: 59 days to 4.8 years), with more than half diagnosed after one year.

Conclusion: Systematic screening of at-risk children from birth, performed by specialized ophthalmologists and followed by examinations under general anesthesia beginning at a few months of age, ensured that all cases of familial Rb were diagnosed within the first year of life. These findings support discontinuing screening sooner than previously advised, for children at low risk (<3%) for familial Rb. The study emphasizes the importance of centralized, standardized protocols to optimize screening durations and reduce healthcare burdens while maintaining safety for at-risk populations.