胃底腺型腺癌2例临床病理观察

Gastric adenocarcinoma of fundic gland type:a clinicopathological analysis of two cases

目的探讨胃底腺型腺癌(GA-FG)临床病理特点、诊断及与其他相似肿瘤的鉴别诊断。方法收集2例GA-FG,分析其临床特点,观察其病理组织学形态及免疫表型特征,并与2例泌酸腺腺瘤进行比较,回顾性分析并复习相关文献。结果GA-FG和泌酸腺腺瘤没有典型的临床表现,2例均以上腹部不适就诊,临床内窥镜下均诊断为息肉。病理组织学GA-FG和泌酸腺腺瘤均有两种细胞组成:一种类似主细胞,另一种类似壁细胞,胃底腺部位的主细胞带及壁细胞带腺体排列紊乱,多数腺体分支状,迷路状,融合,并呈浸润性生长,与正常胃壁组织分界明显,细胞轻度异型性。2例GA-FG浸润至黏膜下,而2例泌酸腺腺瘤局限于黏膜层。免疫组织化学:肿瘤组织MUC6、pepsinogen-Ⅰ,H^(+)/K^(+)-ATP_(ase)、Syn(+),Ki-67增殖指数<5%,β-catenin胞膜或质(+)。2例行ESD治疗,平均随访1~18个月,均未见复发或转移。结论胃底腺型腺癌是WHO(2019)消化系统肿瘤新增组织学类型,其诊断主要依据病理形态学特征及伴有明确黏膜下浸润,预后较好,需要长期随访。

Objective To study the clinicopathological features,diagnosis and differential diagnosis of gastric adenocarcinoma of fundic gland type(GA-FG)from other tumors.Methods Two cases of GA-FG were collected,their clinical characteristics were analyzed,histopathological and immunophenotypic features were observed;the results were compared with that of 2 cases of oxyntic gland adenoma,and the relevant literature was reviewed.Results There was no typical clinical manifestation of GA-FG or oxyntic gland adenoma.Four patients were admitted to hospital with abdominal discomfort.Histopathological GA-FG and secreting acid adenoma both had two cell compositions:one was similar to the chief cell of gastric fundus gland,and the other was similar to the parietal cell.Most of the glands were branched,labyrinthine,fused,and had invasive growth pattern,with obvious boundary with normal gastric wall tissue.The atypia of cells was slight.2 cases of GA-FG invaded into the submucosal layer,while 2 cases of oxyntic gland adenoma were confined to the mucosal layer.Immunohistochemically,the tumor cells were positive for MUC6,pepsinogen-Ⅰ,H^(+)/K^(+)-ATPase,and syn;Ki-67 proliferation index was less than 5%,β-Catenin was also positve in cytoplasm and cell membrane.Two cases of ESD were followed up for an average of 1-18 months without recurrence or metastasis.Conclusion Gastric fundus adenocarcinoma is a new histological type of WHO classification of digestive system tumor in 2019.The diagnosis is mainly based on pathological features and clear submucosal infiltration,with a good prognosis and long-term follow-up.