Hereditary diffuse gastric cancer is a very rare type of gastric cancer, associated with loss of function of a tumor suppressor gene CDH1 which has a high penetrance that can reach 90 % over a lifetime.<h4>Case presentation</h4>Here we present the case of a 31 years old male patient carrying the CDH1 gene who presented for prophylactic total gastrectomy and D1 lymphadenectomy followed by a roux en y esophago-jejunostomy for digestive tract reconstruction. Here, CDH1 is linked to gastric cancer.