Validation of classic and expanded criteria for endoscopic submucosal dissection of early gastric cancer: 7 years of experience in a Western tertiary cancer center. Clinics [Internet]. 2019 Feb. 14 [cited 2024 May 3];73(Suppl. 1):e553s. Available from: https://www.revistas.usp.br/clinics/article/view/154745