原发性胃肠型子宫内膜黏液癌临床病理特征

Clinicopathological features of primary gastrointestinal-type endometrial mucinous carcinoma

目的探讨原发性胃肠型子宫内膜黏液癌(GTEA)临床病理特征、免疫表型、鉴别诊断及预后。方法收集2021-02—2022-07青岛市城阳区人民医院1例原发性GTEA和山东省聊城市人民医院1例原发性GTEA,回顾性分析其临床病理特征,STK11基因突变情况及预后,并复习相关文献。结果2例患者年龄分别为69岁、78岁,术前刮宫病理检查均提示子宫内膜癌,行子宫内膜癌根治术。病理组织学检查:例1主要表现为两种组织学形态,一种呈管状乳头状排列,另一种在富于黏液的背景中可见黏液腺癌细胞团及印戒细胞;例2主要呈筛孔状及绒毛腺管状结构,衬覆黏液柱状上皮,核轻度异型。2例免疫组化染色均显示肿瘤细胞弥漫性表达CEA、Villin、PAX8,不同程度表达P16、CK7、MUC-6,P53野生型,Ki-67增殖指数分别为40%、45%,错配修复蛋白(MMR)检测示微卫星稳定性,STK11基因8号外显子检测,未发现热点突变。例1随访17个月,CT示肺内多发性肿瘤转移,例2随访5个月,病情稳定。结论原发性GTEA是一种较罕见肿瘤,形态及免疫表型具有胃(胃肠)等分化的特点,需要与多种恶性肿瘤进行鉴别,与经典子宫内膜黏液癌相比,预后较差。

Objective To explore the clinicopathological features,immunophenotype,differential diagnosis,and prognosis of primary gastrointestinal-type endometrial mucinous adena carcinoma(GTEA).Methods Two cases of primary GTEA were collected from February 2021 to July 2022.The clinicopathological features,STK11 gene mutation and prognosis were analyzed retrospectively.And the relevant literature was reviewed.Results The age of the 2 patients were 69 and 78 years,respectively.The pathological examination of curettage before operation suggested that radical surgery of endometrial cancer was performed.Histopathologic examination demonstrated that Case 1 showed two types of histology:one was tubular villous and the other was mucinous adenocarcinoma cell and signet ring cells in mucinous background;Case 2 showed cribriform and tubular structure of villous gland,lined with mucinous columnar epithelium,and slightly atypical nucleus.Immunohistochemical staining showed that the tumor cells were diffusely positive for CEA,villin,PAX8,expressed P16,CK7,MUC-6 in varying degrees;P53 was wild type of 2 cases;the proliferation index of Ki-67 was 40%and 45%respectively.Mismatch repair protein(MMR)assay showed that both tumors expressed MLH1,PMS2,MSH2 and MSH6 proteins.Conclusion Primary GTEA is an extremely rare tumor whose morphology and immunological markers are characterized by gastric(gastrointestinal)differentiation and needs to be distinguished from other malignant tumors.It has a poor prognosis compared to classical endometrial mucinous carcinoma.