Introduction: This nationwide study assessed the impact of Lynch syndrome-related risk management guidelines on clinicians' recommendations of risk management strategies to carriers of pathogenic variants in mismatch repair genes and the extent to which carriers took up strategies in concordance with guidelines.
Materials and methods: Clinic files of 464 carriers (with and without colorectal cancer) were audited for carriers who received their genetic testing results in July 2008-July 2009 (i.e. before guideline release), July 2010-July 2011 and July 2012-July 2013 (both after guideline release) at 12 familial cancer clinics (FCCs) to ascertain the extent to which carriers were informed about risk management in accordance with guidelines. All carriers captured by the audit were invited to participate in interviews; 215 were interviewed to assess adherence to recommended risk management guidelines.
Results: The rates of documentation in clinic files increased significantly from pre- to post-guideline for only two out of eight risk management strategies. The strategies with the highest compliance of carriers post-guidelines were: uptake of one or two-yearly colonoscopy (87%), followed by hysterectomy to prevent endometrial cancer (68%), aspirin as risk-reducing medication (67%) and risk-reducing salpingo-oophorectomy (63%). Interrater reliability check for all guidelines showed excellent agreement (k statistics = 0.89).
Conclusion: These results indicate that there is scope to further increase provision of advice at FCCs to ensure that all carriers receive recommendations about evidence-based risk management. A multi-pronged behaviour change and implementation science approach tailored to specific barriers is likely to be needed to achieve optimal clinician behaviours and outcomes for carriers.
Keywords: Cancer risk; Compliance; Genetic testing; Guidelines; Implementation; Lynch syndrome.