N28: Awareness Of Lynch Like Syndrome Within Clinical Genetics –Results From A UK Survey

D. Georgiou1, V. Kiesel1, A. F. Brady1, K. Monahan2

1 – North West Thames Regional Genetics Service. 2 – Chelsea and Westminster Hospitals NHS Foundation Trust.


Aim: UK NICE guidelines (2017) recommend screening of all new colorectal cancers with either immunohistochemistry (IHC) or Microsatellite instability (MSI) testing. Following an abnormal IHC or MSI result, up to 70% of individuals may have no identifiable germline mutation. This group constitutes Lynch-like syndrome (LLS), estimated to represent 3% of colorectal cancer cases.

Evidence suggests the majority of LLS cases are caused by somatic variants in the tumour. Colorectal and extracolonic cancer risks in LLS are increased in comparison to population risks. UK guidelines suggest 2 yearly colonoscopies for individuals with LLS and their first degree relatives; assuming there may be an unknown hereditary cause.

Method: We conducted a survey amongst clinicians practising in regional clinical genetics departments within the UK.  We aimed to explore clinicians’ understanding and management of LLS families. The survey was disseminated by the cancer lead clinician within each department, through a “surveymonkey” link.

Results: We received 44 responses from 19 centres. 40% of participants were aware of the definition of LLS while 27% would offer 2 yearly colonoscopies. There were variations in practice within and between departments.

Conclusion: These results emphasize the importance of increasing awareness of LLS, and contribute towards the need for clear management guidelines.