CDH1 gene mutation, a challenging surgical topic: Case report and literature review

Introduction: Gastric cancer is one of the top 5 cancers worldwide. Most gastric cancers are classified as sporadic with the exception of around 3 % that are associated with specific syndromes or genes. 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.

Case presentation: 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. The patient had a preoperative negative gastroscopy for gastric cancer. On final pathology, few 2 mm foci of signet ring cells involving the lamina propria (T1a) were identified.

Clinical discussion: Randomized clinical trial data concerning HDGC is lacking. Individuals who meet the genetic testing criteria developed by the IGCLC, testing should be obtainable from the legal age of consent that range from 16 to 18 years of age. CDH1 is the main gene that is tested. The mainstay treatment of choice for HDGC is total gastrectomy and Roux-en-Y esophago-jejunostomy in asymptomatic patients but should only be undertaken after baseline endoscopy.

Conclusion: Genetic testing for CDH1 should be carried in high-risk populations. Due to its high penetrance, any person carrying the CDH1 gene should be managed by a prophylactic gastrectomy and D1 lymphadenectomy with close follow up for any future breast neoplasm.