SIOOA1、GLUT-1及Caveolin-1在嗜酸细胞性肾肿瘤中的表达及其鉴别诊断意义

Diagnostic utility of SIOOA1, GLUT-1 and Caveolin-1 in renal tumors with oncocytic features： a comparative study

目的探讨S100A1、GLUT-1及Caveolin-1（Cav-1）在不同类型嗜酸细胞性肾肿瘤细胞中的表达及其在鉴别诊断中的作用。方法利用组织芯片技术结合免疫组织化学方法检测S100A1、GLUT-1及Cav-1在19例嗜酸细胞瘤、15例嗜酸型透明细胞肾细胞癌、11例嗜酸型嫌色细胞癌、7例嗜酸型乳头状肾癌和7例上皮样血管平滑肌脂肪瘤中的表达情况。结果（1）S100A1在嗜酸细胞瘤患者中表达比例为16／19，14／16呈弥漫强阳性；在嗜酸型嫌色细胞癌（2／11）、嗜酸型透明细胞肾细胞癌（10／15）、嗜酸型乳头状肾癌（3／7）、上皮样血管平滑肌脂肪瘤（6／7）均有不同程度表达。S100A1在嗜酸细胞瘤中的表达与嗜酸型嫌色细胞癌差异有统计学意义，而与嗜酸型透明细胞。肾细胞癌、嗜酸型乳头状肾癌、上皮样血管平滑肌脂肪瘤比较，差异均无统计学意义（均为P〉0．05）。（2）GLUT-1在13／15的嗜酸型透明细胞肾细胞癌阳性表达，主要定位于胞膜；在7／19的嗜酸细胞瘤、4／7的嗜酸型乳头状肾癌表达，表现为弱阳性或灶状；11例嗜酸型嫌色细胞癌仅1例散在阳性；所有上皮样血管平滑肌脂肪瘤均阴性。（3）Car-1在6／15的嗜酸型透明细胞肾细胞癌、2／7的嗜酸型乳头状肾癌、5／7的上皮样血管平滑肌脂肪瘤阳性表达；11例嗜酸型嫌色细胞癌中仅2例弱阳性表达，19例嗜酸细胞瘤均为阴性。（4）SIOOA1对嗜酸细胞瘤具有较高的敏感性，但特异性仅为50％；GLUT-1和Cav-1分别对诊断透明细胞性肾癌和上皮样血管平滑肌脂肪瘤具有较高的敏感性和特异性。结论SIOOA1在多种嗜酸细胞性肾肿瘤中均有不同程度表达，其阳性表达有助于嗜酸细胞瘤与嗜酸型嫌色细胞癌的鉴别诊断，但不能作为嗜酸细胞瘤与其他3种嗜酸细胞性。肾肿瘤鉴别的免疫标志物；GLUT．1的高表达有助于嗜酸型肾透明细胞癌的诊断及鉴别诊断；Cav-1在除嗜酸细胞瘤外的4种嗜酸细胞性肾肿瘤均有不同程度表达，尤其在上皮样血管平滑肌脂肪瘤高表达，其阳性表达可除外嗜酸细胞瘤的诊断。

Objective To study the immunohistochemical expression of S100A1, GLUT-1 and Cavolin-1 and its diagnostic significance in renal tumors with oncocytic features. Methods Tissue microarray and immunohistochemical staining for SI00A1, GLUT-1 and Cavolin-1 were carried out in 59 cases of renal tumors with oncoeytic features, including 19 cases of renal oncocytoma, 15 cases of clear cell renal cell carcinoma （CCRCC） with eosinophilic cells, 11 cases of eosinophilic variant of chromophobe renal cell carcinoma, 7 cases of oncocytic papillary renal cell carcinoma and 7 cases of epithelioid angiomyolipoma. Results S100A1 was expressed in renal oncocytoma, with a positive propotion of 16/19 （including 14 cases showing widespread and strong positivity）. On the other hand, the rate of expression of S100A1 was 2/11 in eosinophilic variant of chromophobe renal cell carcinoma, 10/15 in CCRCC with eosinophilic cells, 3/7 in oncocytic papillary renal cell carcinoma and 6/7 in epithelioid angiomyolipoma （P 〉0. 05）. The difference of S100A1 expression between renal oncocytoma and eosinophilic variant of chromophobe renal cell carcinoma was statistically significant. GLUT-1 was located in cell membrane, with a positive rate of 13/15 in CCRCC with eosinophilic ceils, 7/19 in renal oncocytoma, 4/7 （weak） in oncocytic papillary renal cell carcinoma, 1/11 in eosinophilic variant of chromophobe renal cell carcinoma and 0/7 in epithelioid angiomyolipoma. The rate of expression of Car-1 was 6/15 in CCRCC with eosinophilic cells, 2/7 in oncocytic papillary renal cell carcinoma, 5/7 in epithelioid angiomyolipoma, 2/11 （weak） in eosinophilic variant of chromophobe renal cell carcinoma and 0/19 in renal oncocytoma. S100A1 showed high sensitivity and 50% specificity in the diagnosis of renal oncocytoma. GLUT-1 and Cav-1 showed high specificity and sensitivity in the diagnosis of CCRCC and epithelinid angiomyolipoma. Conclusions SI00A1 is widely expressed in various oncocytic renal neoplasms and helpful in differential diagnosis of renal oncocytoma from eosinophilic variant of chromophobe renal cell carcinoma, but not from other 3 oncocytic renal tumors. Overexpression of GLUT-1 can be used in distinction between CCRCC and renal oncocytoma. Car-1 is widely expressed in CCRCC and epithelioid angiomyolipoma but not in renal oncocytoma. Cav-1 expression thus rules out renal oncocytoma.