涎腺乳腺样分泌性癌4例临床病理学特征分析

Mammaryanalogue secretory carcinoma of salivary glands:a clinicopathologic analysis of 4 cases

目的:探讨涎腺乳腺样分泌性癌(MASC)的组织学形态、免疫表型、鉴别诊断及分子特征。方法:收集4例南京医科大学第一附属医院和淮安市第一人民医院病理科2018年7月至12月期间病理诊断为MASC的患者的临床及病理资料,行光镜观察、免疫表型分析及EVT6-NTRK3基因检测,并复习相关文献。结果:患者年龄33~66岁,男女比例1∶1。所有病例均为单发性肿块,直径1.3~2.2 cm。镜下4例肿瘤组织均呈浸润性生长,细胞排列呈微囊状、囊性-乳头状、腺管样、实性片状-巢团状等多样化方式,腔隙内常见嗜酸性分泌物,核分裂像不常见,4例均未见凝固性坏死及脉管、神经侵犯。免疫表型:4例肿瘤细胞细胞角蛋白7(CK7)、S-100、乳腺球蛋白、SOX-10、GATA结合蛋白3(GATA3)均弥漫阳性表达,而DOG-1及其它肌上皮标记P63、α-SMA、Calponin均呈阴性。3例肿瘤Ki-67增殖指数小于20%,另1例约35%。其中3例肿瘤行荧光原位杂交(FISH)检测显示EVT6-NTRK3基因融合。结论:MASC是一种少见的低度恶性涎腺上皮源性肿瘤,形态温和,排列方式多样,其独特的免疫表型S-100、乳腺球蛋白共表达,而DOG-1阴性可将其与其它低级别涎腺肿瘤鉴别开来,必要时FISH检测EVT6-NTRK3融合基因有助于明确诊断。

Objective:To study the clinicopathological features,immunophenotype,differential diagnosis and molecular features of mammary analogue secretory carcinoma(MASC).Methods:Microscope observation,immunophenotyping analysis and EVT6-NTRK3 genetic testing were performed on 4 cases of MASC which were diagnosed by the Department of Pathology,the First Affiliated Hospital of Nanjing Medical University and the Department of Pathology,Huai an First People s Hospital from July to December 2018,and related literature was also reviewed.Results:The patients were aged from 33 to 66 years old.The ratio of male to female was 1∶1.Grossly,all cases revealed a solitary mass(1.3-2.2 cm in diameter).Microscopically,all cases demonstrated a highly infiltrative growth pattern.All tumors showed mixed growth patterns including microcystic,cystic-papillary,tubular,and solid,and eosinophilic secretions could be seen in the cavities.The mitoses were not easily found,and no coagulative necrosis,nerve or vascular invasion were found in these 4 cases.Immunohistochemically,all cases were positive for CK7,S-100,mammaglobin,SOX-10,GATA3.But DOG-1 and the other myoepithelial markers P63,α-SMA,Calponin were negative in all 4 cases.The Ki-67 proliferation index of 3 cases was less than 20%,and the other one case was about 35%.ETV6-NTRK3 gene rearrangement was detected in 3 cases by fluorescence in situ hybridization.Conclusions:MASC is a rare low-grade salivary gland carcinoma exhibiting moderate morphology and diverse arrangement patterns.Its distinct histochemical feature-strong S-100,mammaglobin positivity and DOG-1 negativity,can help to differentiate it from other low-grade salivary gland tumors.ETV6-NTRK3 gene rearrangement tests can be used as an auxiliary diagnostic tool if necessary.