肾上皮样血管平滑肌脂肪瘤的TFE3蛋白表达和TFE3基因荧光原位杂交分析

TFE3 protein expression and analysis of TFE3 gene fluorescence in situ hybridization of renal epithelioid angiomyolipoma

目的探讨肾脏上皮样血管平滑肌脂肪瘤的TFE3的蛋白表达及TFE3基因异常情况。方法回顾性收集2011年1月至2021年8月首都医科大学附属北京友谊医院诊断为肾脏上皮样血管平滑肌脂肪瘤14例的病例资料,观察记录所有病例的病理组织特征。行TFE3免疫组织化学检测,对其中TFE3阳性的病例行荧光原位杂交(FISH)检测。结果14例男女比例1∶1,平均39.8岁。大部分病例(10/14)的肿瘤细胞全部为上皮样细胞构成。3例TFE3弥漫中至强阳性,其余11例完全阴性。3例TFE3阳性的肿瘤无TFE3基因重排,但其中2例有TFE3基因扩增。结论TFE3基因重排在肾脏上皮样血管平滑肌脂肪瘤中罕见,TFE3阳性不代表肿瘤细胞一定具有TFE3基因重排,TFE3基因扩增也可致肿瘤表达TFE3蛋白,极少数没有TFE3基因异常的肾脏上皮样血管平滑肌脂肪瘤可异常表达TFE3蛋白。TFE3基因扩增需与肿瘤性多核巨细胞的多信号鉴别。

Objective To analysis TFE3 protein expression and TFE3 gene abnormality of renal epithelioid angiomyolipoma.Methods The data of 14 cases of renal epithelioid angiomyolipoma diagnosed by Beijing Friendship Hospital,Capital Medical University from January 2011 to August 2021 were retrospectively collected.The pathological characteristics of all cases were observed and recorded.All 14 cases were labeled for TFE3 by immunohistochemistry,and the cases with TFE3 protein expression were performed with fluorescence in situ hybridization(FISH).Results The ratio of male to female was 1∶1,with an average age of 39.8 years.Most of the cases(10/14)were purely composed of epithelioid neoplastic cells.Only 3 cases were diffusely moderately to strongly positive for TFE3,the remaining 11 cases were completely negative.FISH showed that all three TFE3 positive tumors had no TFE3 gene rearrangement,but 2 of them had TFE3 gene amplification.Conclusion TFE3 gene rearrangement is rare in renal epithelioid angiomyolipoma.The positive expression of TFE3 protein does not mean that tumor cells have TFE3 gene rearrangement.The amplification of TFE3 gene can also result in TFE3 protein expressing.A few renal epithelioid angiomyolipomas without TFE3 gene abnormality can also abnormally express TFE3 protein.Amplification of TFE3 gene in renal epithelioid angiomyolipoma must be differentiated from multi-signals of multinuclear giant tumor cells.