Endoscopic Ultrasound Has Limited Utility in Diagnosis of Gastric Cancer in Carriers of CDH1 Mutations.

A total of 1%-3% of gastric cancers are related to hereditary syndromes, including hereditary diffuse gastric cancer syndrome (HDGC), which is characterized by pathogenic variants of the CDH1 gene and a high risk of lifetime incidence of both diffuse gastric cancer (DGC) and lobular breast cancer.1,2 HDGC is suspected in families with DGC or lobular breast cancer, especially when either is diagnosed before 50 years of age or when present in multiple family members.3 As individuals with HDGC have up to a 70% lifetime risk of DGC, prophylactic total gastrectomy is recommended.1,2 For patients who defer surgery, annual endoscopic surveillance via the Cambridge protocol is recommended, comprising biopsies of any lesions and a minimum of 30 random biopsies from the antrum, transitional zone, body, fundus, and cardia.1.