Objective: To investigate the clinicopathological characteristics of primary pulmonary NUT carcinoma. Methods: A total of 7 cases of primary pulmonary NUT carcinoma were collected from Fujian Provincial Hospital (n=5), Fuzhou Taijiang Hospital (n=1) and Binzhou City People's Hospital of Shandong Province (n=1) from January 2021 to April 2023. The clinical, histopathological, and immunohistochemical features were analyzed, and NUT rearrangement were detected by fluorescence in situ hybridization (FISH) with break-apart probes. Results: Seven cases were all male with age ranging from 32 to 73 years. The main clinical manifestations were cough, expectoration and chest tightness. Microscopically, NUT carcinoma was composed of monotonous proliferation of primitive-appearing small-to-medium round cells, with few eosinophilic cytoplasm, arranged in solid sheets, nests or clusters. Abrupt keratinization was typically observed in 4 cases (4/7), with high mitotic activities and necrosis. Immunohistochemistry (IHC) showed that the tumors were positive for NUT (7/7), CK7 (4/4), CK5/6 (5/6), p40 (6/7). Ki-67 index were 30%-80%. NUT gene segregation (7/7) was detected by FISH break probes. Conclusions: Primary pulmonary NUT carcinoma is rare and highly malignant. Diagnosis depends on histopathology and IHC, with molecular detection as an adjunct for diagnosis. Pathologists should be aware of the clinicopathological characteristics to avoid misdiagnosis.
目的： 探讨原发性肺NUT癌的临床病理学特征。 方法： 收集2021年1月至2023年4月福建省立医院5例、福州市台江医院1例、山东省滨洲市人民医院1例，共计7例原发性肺NUT癌，分析临床病理学特征、免疫表型等，采用荧光原位杂交（FISH）断裂-分离探针检测NUT重排，随访治疗及预后，并系统性复习文献。 结果： 7例患者均为男性，年龄32~73岁，临床表现以咳嗽、咳痰、胸闷等为主。镜下表现以小圆细胞为主，排列呈实性、巢状、片状、簇状，细胞质较少、嗜酸性，核分裂象易见，伴坏死，4例（4/7）见骤然角化区；免疫组织化学弥漫表达NUT（7/7）、细胞角蛋白（CK）7（4/4）、CK5/6（5/6）、p40（6/7）；Ki-67阳性指数为30%~80%。FISH断裂-分离探针检测到NUT基因分离（7/7）。 结论： 原发性肺NUT癌罕见，高度恶性，诊断依赖病理组织学及免疫组织化学检测，必要时分子检测辅助诊断；病理医师应提高认识，避免误诊。.