These guidelines from the UK Cancer Genetics Group were developed using data from individuals ascertained as carriers of cancer susceptibility genes through diagnostic, family history or other clinical pathways where evidence supports standard actionability of the identified variant.
These recommendations are based on evidence around the likely benefits of proposed interventions weighed against any possible harms for standard penetrance in clinically ascertained cohorts.
The risks and benefits of these interventions for individuals identified as carriers of cancer susceptibility genes through other routes, such as incidental findings or population screening have not been clearly established. Clinical judgement needs to be exercised when counselling and implementing on-going surveillance, early detection and prevention interventions where penetrance may be lower than expected and personalised more conservative management may be considered (e.g. surveillance versus irreversible risk-reducing surgery).
https://www.ukcgg.org/information-education/ukcgg-leaflets-and-guidelines
Lynch Syndrome Ireland 