The Hereditary Diffuse Gastric Cancer (HDGC) syndrome is due to a mutation in the CDH-1 gene that predisposes patients to a high lifetime risk of developing gastric cancer. As such, a total gastrectomy is typically recommended for patients with this syndrome. In this case, the patient presented with an incidentally discovered CDH-1 mutation on genetic testing obtained after she was diagnosed with early-onset rectal cancer. She underwent a prophylactic total gastrectomy with a retrocolic Roux-en-Y esophagojejunostomy. Her postoperative course was unremarkable, and she was discharged on postoperative day 3. Her pathology demonstrated several foci of signet ring cell carcinoma limited to the mucosa. This video demonstrates an experienced surgeon’s technique for performing a prophylactic total gastrectomy with a Roux-en-Y esophagojejunostomy reconstruction.