Knowledge of genetics in familial retinoblastoma.

PURPOSE: To evaluate knowledge of retinoblastoma inheritance among parents of children with familial retinoblastoma, and to compare this to timing of eye examination for at-risk children, disease severity at diagnosis, treatment burden, and outcome.

METHODS: A retrospective review of familial retinoblastoma cases that presented at Alexandria Main University Hospital was performed. Primary outcome measures were parental knowledge of familial retinoblastoma (disease, heritability) and subsequent action (early screening or not) and their impact on tumor burden (classification at diagnosis, potential threat to vision, ocular salvage, and life), treatment burden, and treatment success (avoidance of enucleation and irradiation).

RESULTS: Twenty-three eyes of 13 familial retinoblastoma cases were included. Probands were parents in 9 (69%) and older siblings in 4 (31%) cases. At time of diagnosis of the first affected children, none (0%) of the parental probands knew that newborns should be screened, in contrast to all parents with a child proband (4/4, 100%; p = 0.004). Early eye screening was significantly associated with lower tumor burden (p = 0.03), lower treatment burden (p = 0.04), higher rate of ocular salvage (p = 0.01), and better visual outcome (p = 0.01).

CONCLUSION: Parental knowledge of retinoblastoma nature and heritability is crucial to good patient outcomes, but translating this knowledge into appropriate action (i.e. screening of at-risk children) is still deficient.