关键词: 早期胃癌, 淋巴结转移, 原始表型, 内镜下切除术, 临床病理学意义

Abstract: Objective：To investigate the existence of primitive phenotypes in differentiated early gastric cancer(EGC) and its clinicopathological significance. Methods： 82 differentiated EGC pathological specimen were selected in our hospital from March 2018 to February 2022， and the samples were stained by immunohistochemistry，periodic acid schiff(PAS) and D-PAS.The expression of primitive markers in primitive phenotypic differentiated EGC，the relationship between primitive phenotype of differentiated EGC and clinicopathological features，and the relationship between clinicopathological features of differentiated EGC and lymph node metastasis(LNM) were observed to analyze whether differentiated EGC met the indications of endoscopic resection and whether LNM existed. Results：10.98% of all differentiated EGC cases had primitive phenotypes.Patients with the primitive phenotype had deeper invasions and higher rates of ulcers and lymphatic infiltration than those without the primitive phenotype. In addition， the incidence of LNM in patients with primitive phenotype (66.67%) were higher than that of patients without primitive phenotype(24.66%) (P<0.05). Multivariate analysis showed that the presence of a primitive phenotype was an independent risk factor for LNM(P=0.002).LNM occurred in two cases with primitive phenotypes，and all met the extended indications for endoscopic resection of differentiated EGC. Conclusion：A few differentiated EGCs have primitive phenotypes，which are closely related to LNM and are independent risk factors for LNM.Given its highly invasive behavior，differentiated EGC with primitive phenotype should be evaluated according to stricter criteria prior to endoscopic resection，or additional surgical procedures should be considered after endoscopic resection.

Key words: Early gastric cancer, Lymph node metastasis, Primitive phenotype, Endoscopic resection, Clinicopathological significance