Efficacy and safety of endoscopic submucosal dissection in the treatment of early cardia cancer and non-cardia cancer with submucos

<b>Objective</b> To analyze the clinicopathological features of submucosal early cardia and non-cardia cancer，and evaluate the efficacy of endoscopic submucosal dissection (ESD) for treating early gastric cancer (EGC) with submucosal infiltration. <b>Methods</b> The clinical data of EGC patients with submucosal infiltration who received ESD in Nanjing Drum Tower Hospital from January 2014 to December 2019 were retrospectively analyzed, including 202 cases of cardia cancer (206 lesions) and 112 cases of non-cardia cancer (119 lesions). The basic data, pathological features, short-term and long-term prognosis of the two groups were compared. <b>Results</b> Compared with non-cardia cancer group, in cardia cancer group,the patients had older age and a lower proportion of gastric cancer family history (P＜0.05), and higher proportions of concave lesion appearance, infiltration depth achieved SM2 (depth of submucasal infiltration＞500μm), moderate-to-severe atrophic gastritis and deep cystic gastritis (P＜0.05). There was no significant difference in complete resection rate (82.04%vs 81.51%,χ2 0.014,P=0.906), curative resection rate (38.83%vs 42.02%,χ2 0.318,P=0.573) between cardia cancer group and non-cardia cancer group, but the incidences of positive vertical margin, en bloc resection and postoperative stenosis of cardia cancer group were higher (P＜0.05). The postoperative bleeding rate was 3.96% in cardia cancer group and 5.36% in non-cardia cancer group, and no perforation occurred in either group. The incidences of synchronous cancer, metachronous cancer, lymph node metastasis and distant metastasis after ESD in the two groups were low, and no statistical difference was found (P＞0.05). Follow-up to July 15, 2020, except for the lost cases, the overall survival rate (95.31%vs 97.20%) and disease-specific survival rate (97.92%vs 97.20%) were all high in cardia cancer and non-cardiac cancer groups,and showed no statistically significant difference between two groups (P＞0.05). <b>Conclusion</b> Early-stage cardia cancer and non-cardia cancer with submucosal infiltration exhibit different clinicopathological features. ESD is an effective treatment for the two, due to its high complete resection rate, few surgical complications, and low postoperative recurrence and metastasis rates.