Nationwide retrospective cohort study of gastric and duodenal cancer in individuals with Lynch syndrome

Lynch syndrome (LS) increases the risk of gastric cancer (GC) and duodenal cancer (DC), particularly in individuals with pathogenic variants (PVs) in MLH1 AND MSH2. A nationwide retrospective cohort study in The Netherlands (1989-2021) found that among 1002 individuals with high-risk PVs (MLH1, MSH2, and EpCAM) and 765 individuals with low-risk PVs (MSH6 and PMS2), 29 GCs (1.6%) and 39 DCs (2.2%) were diagnosed. The figure shows that cumulative incidence of GC and DC under the age of 50 years was very low (≤1%) for all individuals, while the risk was substantial among high-risk PV carriers at age 70 and age 75 years. The authors conclude that the age at onset of esophagogastroduodenoscopy surveillance, the yield of GC and DC during surveillance, and its cost-effectiveness should be subject of future studies.