Clinicopathological features and prognosis of gastric tube cancer after esophagectomy for esophageal cancer: a nationwide study in Japan

Background: Survivors of esophageal cancer post-esophagectomy may sometimes develop gastric tube cancer (GTC). However, its clinical characteristics have not been elucidated. We conducted a retrospective nationwide survey of GTCs to clarify them. Methods: A questionnaire on GTCs was sent by e-mail and mail to 116 institutions certified by the Japan Esophageal Society. A total of 608 GTC cases diagnosed and treated between 2001 and 2015 were registered from 62 institutions. Results: The median age at diagnosis was 71 years, with 88.9% being diagnosed with stage I. Sixty percent of GTC cases were in the anal third of the gastric tube and 79.7% were differentiated adenocarcinomas. The median interval between esophagectomy and GTC diagnosis was 6 years, with approximately 25% of patients being diagnosed more than 10 years later. The 5-year overall survivals (5-OSs) after endoscopic and surgical treatments for GTC were 75.9% and 52.7%, respectively. Patients whose GTC was diagnosed without symptoms or by regular follow-up examination showed better 5-OSs compared to others (69.7% vs. 41.2%, p < 0.0001; and 71.4% vs. 41.8%, p < 0.0001, respectively). The prognosis of GTC cases diagnosed within 2 years of the preceding upper gastrointestinal endoscopy (UGI) was better than that in cases diagnosed longer than 2 years (5-OS: 73.4% vs. 48.8%, p < 0.05). Conclusion: This nationwide survey revealed the clinicopathological features of GTCs for the first time. Early detection is important in improving the prognosis of GTC, and it is recommended that UGI endoscopy be continued every 2 years for 10 or more years after esophagectomy.