| Endoscopic resection (ER) is a minimally invasive treatment for esophagogastric junctional (EGJ) cancers. However, detailed indication of ER for EGJ cancer is not stated in Japanese guideline. We therefore conducted a multicenter retrospective study in 13 high-volume centers to elucidate the risk of metastasis in EGJ adenocarcinoma and esophageal adenocarcinoma. Methods: A total of 458 patients (217 surgically resected and 241 endoscopically resected cancers) were included. Metastasis was considered positive if there was metastasis in the surgical specimen or clinically confirmed metastasis during follow-up. Metastasis was considered negative if no metastasis was identified in resected specimens and during follow-up in patients treated surgically or no metastasis during follow-up for >5 years in patients treated by ER. Results: Metastasis was identified in 72 patients. Multivariate analysis confirmed lymphovascular involvement, a poorly differentiated component, and lesion size >30 mm as independent risk factors for metastasis. No metastasis was detected in mucosal cancers without lymphovascular involvement and a poorly differentiated component (0/186 lesions) or in cancers invading the submucosa (1-500 μm) without lymphovascular involvement, a poorly differentiated component, and <=30 mm (0/ 32 lesions). Conclusion: Mucosal and submucosal cancers (1-500 μm invasion) without risk factors have a low incidence of metastasis and may thus be good candidates for ER. |
