Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection

BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract, and endoscopic submucosal dissection (ESD) is the preferred treatment for early-stage gastric cancer. The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD. AIM To analyze the features of gastric mucosal tumors at different differentiation levels, and to explore the prognostic factors of ESD. METHODS We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021, according to the latest Japanese guidelines (sixth edition), and divided them into low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia (HGIN), and differentiated and undifferentiated early carcinoma. They are followed up by endoscopy, chest and abdominal computed tomography at 3, 6 and 12 months after ESD. We compared clinicopathologic characteristics, ESD efficacy, and complications with different degrees of differentiation, and analyzed the related factors associated with ESD. RESULTS HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients (P < 0.001) and accounted for more 0-IIc (P < 0.001), atrophic gastritis was common (P < 0.001), and irregular microvascular patterns (IMVPs) and demarcation lines (DLs) were more obvious (P < 0.001). There was more infiltration in the undifferentiated carcinoma tissue (P < 0.001), more abnormal folds and poorer mucosal peristalsis (P < 0.001), and more obvious IMVPs, irregular microsurface patterns and DLs (P < 0.05) than in the LGIN and HGIN tissues. The disease-free survival rates at 2, 5, and 8 years after ESD were 95.0%, 90.1%, and 86.9%, respectively. Undifferentiated lesions (HR 5.066), white moss (HR 7.187), incomplete resection (HR 3.658), and multiple primary cancers (HR 2.462) were significantly associated with poor prognosis. CONCLUSION Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics, which are closely related to the safety and efficacy of ESD.