Extent of Surgery in Lynch Syndrome Associated Colorectal Cancer and Endometrial Cancer Risk Reduction: Seeing the Forest for the Trees

Abstract Lynch syndrome, the most common hereditary colorectal cancer syndrome, is caused by inherited pathogenic germline mutations in one of the mismatch repair genes. Beyond colorectal cancer risk, Lynch syndrome is a pan-cancer syndrome necessitating lifelong high-risk surveillance measures and/or risk-reducing surgical interventions. Patients with a diagnosis of colon cancer in the setting of Lynch syndrome have long faced the decision of pursuing extended surgical interventions for risk reduction versus limited segmental resections, with mismatch repair gene-specific cancer risks now helping to inform such decisions. Importantly, recent advances in the field, such as the remarkable efficacy of immunotherapy, the value and limitations of colonoscopy surveillance, and the increased utilization of cancer prevention methods, including the promise of vaccines, have made decisions regarding the optimal management of such patients even more complex. Although there is no one-size-fits-all answer, given the importance of such decisions on patients' quality of life, we advocate for shared and individualized decision-making that encompasses the patient's perspective as well as the expertise of surgeons and physicians across varied disciplines. Such decisions get more complicated when patients have to consider risk-reducing surgery for endometrial cancer in the absence of cancer as a prophylactic measure as well. Thus, informed discussion about the available surveillance and prevention armamentarium is the mainstay of achieving well-informed shared decisions in these cases.