Non-Ocular Cancers in Parents of Patients Diagnosed with Retinoblastoma in Britain 1949 to 1987.
RB1 mutation-carrier parents have a higher lifetime risk of non-eye cancers.
Non-Ocular Cancers in Parents of Patients Diagnosed with Retinoblastoma in Britain 1949 to 1987.
Mutations in the retinoblastoma gene (RB1) are associated with risks of both retinoblastoma and other cancers.
A cohort of 1180 parents of children with retinoblastoma were categorised according to the likelihood that they carried an RB1 mutation and followed up for cancer through national records.
carrying the mutation without eye cancer still means far higher lifetime cancer risk
In total, 183 non-ocular cancers were identified among the parents.
Parents who themselves had retinoblastoma had a significantly higher risk of non-ocular cancer than the general population: for fathers, the Standardised Incidence Ratios was 3.56 (95% confidence interval (CI) 1.84-6.22); for mothers, it was 3.25 (1.49-6.18).
For the very small group of parents known to be carrying a germline RB1 mutation but not affected by retinoblastoma, there was a lower and non-significant increase in risk (Standardised Incidence Ratios = 1.9).
Parents categorised as either possible carriers or probable non-carriers had similar observed risks to the general population.
Our results confirm that parents who themselves had retinoblastoma have an increased risk of subsequent cancers, and parents who are not mutation carriers have a risk similar to the general population.