Cancer surveillance in Lynch syndrome: A scoping review of international and national guidelines.

Lynch syndrome is the most common hereditary cancer predisposition syndrome and confers substantial lifetime risk for colorectal, endometrial, ovarian, gastric, urothelial, and other malignancies. Colonoscopy and risk-reducing strategies substantially reduce morbidity and mortality; however, international and national guidelines vary widely in scope, recommended surveillance modalities, timing, intervals, and evidence grading. In this study, we conducted a scoping review to map and compare cancer surveillance, risk-reducing surgery, and chemoprevention recommendations for Lynch syndrome and identify areas of consensus, divergence, and evidence gaps. We searched PubMed, Embase, Cochrane Library, and professional society and health-agency websites (January 2025; updated August 2025) for English-language guidelines published between 2015 and 2025. Thirty-three guidelines met the inclusion criteria. Colonoscopy was universally endorsed, but recommended initiation ages ranged from 20 to 35 years and intervals from 1 to 3 years, depending on the mismatch repair gene, with shorter intervals for individuals with pathogenic variants in MLH1 or MSH2. Recommendations for extracolonic surveillance varied substantially; most guidelines supported endometrial biopsy and consideration of prophylactic hysterectomy with bilateral salpingo-oophorectomy after childbearing. Gastric, pancreatic, urothelial, and other screening strategies were inconsistently endorsed, often limited to selected high-risk subgroups. Aspirin chemoprevention was widely supported despite dose variability. These findings highlight opportunities for harmonization, gene-stratified precision prevention, and higher-quality prospective evidence to guide care.