Comparison between endoscopic submucosal resection and surgery for the curative resection of undifferentiated-type early gastric cancer within expanded indications: a nationwide multi-center study

Ji Yong Ahn, Young-II Kim, Woon Geon Shin, Hyo‐Joon Yang, Su Youn Nam, Byung‐Hoon Min, Jae Young Jang, Joo Hyun Lim, Jie‐Hyun Kim, Wan‐Sik Lee, Bong Eun Lee, Moon Kyung Joo, Jae Myung Park, Hang Lak Lee, Tae‐Geun Gweon, Moo In Park, Jeongmin Choi, Chung Hyun Tae, Young‐Woo Kim, Boram Park, II Ju Choi