Aims: Hereditary diffuse gastric cancer (HDGC) is an autosomal-dominant inherited form of gastric cancer associated with inactivating germline mutations in the CDH1 gene. We set out to outline the role of CDH1 in HDGC. Investigation of a family suspected as having HDGC is discussed. The role of surgery in the management of affected individuals is then examined.
Methods: A search was conducted of Medline and the National Library of Medicine to identify key articles concerning CDH1 gene mutations, familial gastric cancer and gastrectomy. Further, relevant articles were obtained by manual scanning of the reference lists of identified papers. Mutation-specific CDH1 genetic testing was performed on six living family members and on gastric tissue obtained from two deceased members.
Results: CDH1 mutations cause inactivation of the cell adhesion protein E-cadherin. Carriers of the CDH1 germline gene mutation develop an aggressive, diffuse, submucosal gastric cancer at an early age. Current endoscopic screening is ineffective at detecting HDGC. The presence of a CDH1 germline gene mutation was confirmed in both deceased family members and also in four of the six living members tested.
Conclusion: Genetic counselling and CDH1 gene mutation testing is indicated in families with suspected HDGC. In the absence of a satisfactory surveillance mechanism, prophylactic total gastrectomy would appear to be an appropriate therapeutic option in mutation carriers.