摘要目的：分析钙黏蛋白17（CDH17）在后肾腺瘤中的表达情况，探讨CDH17在后肾腺瘤诊断中的价值。方法采用免疫组织化学EnVision法检测21例后肾腺瘤、16例上皮为主型肾母细胞瘤（e-WT）和20例实性为主型乳头状肾细胞癌（s-PRCC）中CDH17、WT1、CD57、P504S、上皮细胞膜抗原（EMA）的表达，以及常见的肾脏上皮性肿瘤包括透明细胞性肾细胞癌（CCRCC）、嫌色性肾细胞癌（CHRCC）、嗜酸细胞腺瘤各10例中CDH17的表达。结果21例后肾腺瘤中有20例（95.2％） CDH17呈膜阳性表达于腺泡状、乳头状或小管状等组织学结构，而16例e-WT中仅1例表达CDH17，20例s-PRCC均为阴性（P＜0.05）。 WT1在所有后肾腺瘤（100％）和e-WT（16／16）中阳性，在s-PRCC中阴性。 CD57在所有后肾腺瘤（100％）中强阳性，而在e-WT和s-PRCC中也分别有13例（13／16）和9例（45.0％，9／20）阳性。 P504S在所有s-PRCC（100％）中强阳性，后肾腺瘤中3例（14.3％，3／21）阳性，e-WT中均阴性。 EMA在后肾腺瘤、e-WT、s-PRCC中的阳性表达率分别为19.0％（4／21）、14／16、17／20。 CDH17在后肾腺瘤诊断中的敏感性和特异性分别为95％和97％。所有CCRCC、CHRCC和嗜酸细胞腺瘤中未见CDH17阳性表达。结论 CDH17是诊断后肾腺瘤高度敏感和特异的标志物，有助于与具有相似形态学的肾脏肿瘤以及其他常见肾脏上皮性肿瘤的鉴别。

abstractsObjective To study the expression of cadherin 17 ( CDH17 ) in metanephric adenoma ( MA ) , and to explore the value of CDH 17 in the diagnosis of metanephric adenoma.Methods Immunohistochemical EnVision method was used to detect the expression of CDH 17, WT1, CD57, P504S and EMA in 21 cases of MAs, 16 epithelial-predominant Wilms tumors ( e-WT), and 20 solid variant of papillary renal cell carcinomas ( s-PRCC).The expression of CDH17 was also examined in other common renal epithelial tumors , including 10 cases of clear cell renal cell carcinomas ( CCRCC ) , 10 chromophobe renal cell carcinomas ( CHRCC), and 10 oncocytomas.Results Twenty (95.2%) of 21 cases of MAs demonstrated membranous CDH 17 immunoreactivity in all components ( acinar , tubular , and papillary ) , whereas only 1 (1/16) e-WT was positive for CDH17 and all s-PRCCs were negative ( P<0.05).WT1 was negative in s-PRCC and was positive in all cases of e-WT ( 16/16 ) and MA ( 100%,21/21 ).All MAs (100%) were strongly positive for CD57;however, this marker was also positive in 13 (13/16) e-WTs and 9 (45.0%,9/20) s-PRCCs.P504S was strongly positive in all s-PRCCs (100%), but reactivity was seen in 3 (14.3%,3/21) MAs and all e-WTs were negative.The positive rates of EMA in MAs, e-WTs and s-PRCCs were 19.0%(4/21),14/16 and 17/20, respectively.The sensitivity and specificity of CDH17 in the diagnosis of MA were 95% and 97%.CDH17 was negative in all cases of CCRCC , CHRCC and oncocytoma.Conclusions CDH17 is a highly sensitive and specific marker for MA and should be considered in the immunohistochemistry panel for distinguishing MA from its mimics and other common renal epithelial tumors.