摘要目的:探讨ETV6基因重排鼻腔鼻窦低度恶性非肠型腺癌的临床病理、免疫表型及分子遗传学特征。方法:收集复旦大学附属眼耳鼻喉科医院病理科2015年1月至2020年1月诊断为鼻腔鼻窦原发性上皮性恶性肿瘤病例，通过形态学观察和免疫组织化学检测、荧光原位杂交（FISH）技术，筛选出ETV6基因重排鼻腔鼻窦低度恶性非肠型腺癌行临床病理分析，并复习相关文献。结果:鼻腔鼻窦原发性上皮性恶性肿瘤550例，腺癌82例，其中低度恶性非肠型腺癌29例，从中筛选出ETV6基因重排鼻腔鼻窦低度恶性非肠型腺癌3例。男性2例，女性1例，平均年龄54岁（37~64岁）。临床表现为鼻腔狭窄、鼻塞、鼻出血。鼻内镜下见表面光滑新生物。影像学显示鼻腔鼻窦膨胀性肿块占位。大体肿瘤切面灰白灰黄色，质地中等，最大径2~3 cm。镜下肿瘤无包膜，界限清楚，呈膨胀性生长；瘤细胞体积较小、形态温和，立方状、矮柱状，排列呈规则的腺管状、小梁状。胞质嗜酸，细胞核位于基底，核仁不明显。免疫组织化学标志物细胞角蛋白7（CK7）、SOX-10、DOG1、波形蛋白均弥漫阳性；S-100蛋白局灶阳性；GCDFP-15、Mammaglobin、甲状腺转录因子1（TTF1）、CD56、CK20、NR4A3阴性；Ki-67阳性指数低（<5%）。3例FISH ETV6基因重排阳性，2例FISH NTRK3基因重排阳性。3例患者均行手术切除，其中1例术后辅以放疗。3例随访12~25个月，均未发现肿瘤复发。结论:ETV6 基因重排鼻腔鼻窦低度恶性非肠型腺癌是一种新命名的少见的低度恶性肿瘤，组织学形态与其他低度恶性鼻腔鼻窦腺癌及部分涎腺肿瘤有相似之处，免疫组织化学染色及ETV6基因检测可帮助明确诊断。

abstractsObjective:To investigate the clinicopathologic features, immunophenotype, molecular genetic changes of ETV6-rearranged low-grade sinonasal non-intestinal-type adenocarcinoma (ETV6-RLGSNAC).Methods:Primary sinonasal epithelial malignant tumors were collected from January 2015 to January 2020 in the Department of Pathology, Eye, Ear, Nose and Throat Hospital affiliated to Fudan University. Through morphological observation, immunohistochemical detection and fluorescence in situ hybridization (FISH), ETV6-RLGSNAC was screened out for clinicopathological feature analysis, and relevant literatures were reviewed.Results:There were 550 cases of primary sinonasal epithelial malignant tumors, among which 82 cases were adenocarcinoma. There were 29 cases of low-grade non-intestinal adenocarcinoma, only 3 cases of ETV6-RLGSNAC were screened out. Of the 3 patients, 2 cases were male and 1 case was female, with a mean age of 54 years (range 37-64 years). The main clinical manifestations were nasal stenosis, nasal obstruction and epistaxis. A neoplasm with smooth surfaces was observed under nasal endoscopy. Imaging showed an expansive mass in the sinonasal area. Gross examination showed gray-yellow cut surface with firm texture and a maximum diameter of 2-3 cm. Microscopically, tumors were non-encapsulated and well-circumscribed with expansive growth pattern. The tumor cells were small and mild, cylindrical and cuboidal, and arranged in regular glandular and trabecular patterns. The cytoplasm was eosinophilic and the nuclei were basally located with inconspicuous nucleoli. By immunohistochemistry (IHC), CK7, SOX-10, DOG1 and vimentin were positive and S-100 expressed in small clusters of cells in all cases. GCDFP-15, CD56, CK20, mammaglobin, TTF-1, NR4A3 were all negative. The Ki-67 value-added index of all cases was low (<5%). ETV6 gene rearrangement was confirmed in all the cases by FISH, and two cases had NTRK3 gene rearrangement. All three patients underwent radical resection after diagnosis, and one also had adjuvant radiotherapy. All three patients were available with a follow-up time of 12-25 months, and all were recurrence free.Conclusions:ETV6-RLGSNAC is a rare low-grade and newly named non-intestinal adenocarcinoma. The histomorphology is similar to other low-grade nasal sinonasal adenocarcinomas and some salivary gland tumors. IHC and FISH are useful for the diagnosis and differential diagnosis.