Patients who carry CDH1 germline mutations have a lifetime risk of >70 % of developing diffuse gastric cancer with a 5-year survival of less than 20 %.7,8 Female carriers also have an increased risk to develop lobular breast cancer.9–11 Surgery eliminates the high risk of developing diffuse gastric cancer in patients with germline CDH1 mutations and therefore is the treatment of choice. Here, CDH1 is linked to Hereditary breast cancer.