BACKGROUND: Hereditary diffuse gastric cancer (HDGC) results from truncating mutations of the CDH1 (E-cadherin) gene. It is an autosomal dominant cancer susceptibility syndrome with a lifetime risk of diffuse gastric cancer (DGC) of 60-80%, with a mean age of onset of 37 years. There exists no adequate screening test for DGC. Early intramucosal diffuse/signet-ring cell carcinomas have been found in prophylactic total gastrectomy (PTG) specimens following normal preoperative endoscopy. Total gastrectomy has been advocated on a prophylactic basis. The aim of this study was to report our experience with PTG in 23 patients from the Canadian province of Newfoundland and Labrador. This is the largest series worldwide. METHODS: A retrospective study of consecutive patients undergoing PTG for HDGC was performed. All patients were confirmed to have a truncating mutation of the CDH1 gene. RESULTS: Twenty-three patients underwent PTG between February 2006 and November 2008. Major complications were found in 4/23 patients (17%), with no mortality. Two of 23 patients (9%) had positive mucosal biopsies on preoperative EGD. Twenty-two of 23 patients (96%) had evidence of diffuse/signet-ring carcinoma on final standardized pathological evaluation. Therefore, 21/23 (91%) were not picked up by preoperative EGD screening. CONCLUSIONS: PTG can be performed in patients with HDGC with a low rate of serious complications. Methods of reconstruction incorporating a pouch reservoir and preservation of the postgastric branches of the vagus nerves need to be explored. More refined penetrance estimates, effective screening protocols, and long-term psychological and functional outcomes following PTG require organized multicenter collaborative efforts.