肾混合性上皮间质肿瘤病理学特点

目的:探讨肾混合性上皮间质肿瘤(mixed epithelial and stromal tumor of the kidney,MESTK)的临床病理学特点.方法:观察1例罕见的青春期男性MESTK的临床资料、镜下组织学表现、免疫组织化学染色特点及鉴别诊断并复习相关文献.结果:患者为16岁男性.临床表现主要为排尿不畅,右腰腹部肿物.影像学检查示肾巨大囊实性占位性病变.病理检查示肿瘤肉眼呈囊实性结构,镜下由上皮和间质成分共同构成,上皮成分主要为小至中等大的腺管,间质为疏松排列的梭形细胞,可见束状分布的平滑肌组织但缺乏女性卵巢间质样成分.免疫组织化学染色示,上皮细胞AEI/AE3阳性,间质细胞雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone recep-tor,PR)、平滑肌肌动蛋白(smooth muscle actin,SMA)、结蛋白(Desmin)、波形蛋白(Vimentin)阳性,部分上皮ER、PR、CDIO、Vimentin阳性,上皮成分及间质成分HMB-45、S-100、α一抑制素(α-inhibin)及wT-1阴性.患者行肿瘤切除术后随访5个月未见复发.结论:ESTK为具有独特组织病理学特点的一种罕见的发生于肾的肿瘤,多见于围绝经期女性,大部分患者有长期激素类药物应用史和/或肥胖史或子宫/双侧附件手术史,本例特殊之处在于患者为青春期男性,且无激素类药物应用史和/或肥胖史或泌尿生殖系统手术史,考虑青春期体内激素水平的剧烈波动可能为年轻男性发生本病的重要诱因.

Pathological characteristics mixed epithelial and stromal tumor of kidney

OBJECTIVE:To study the clinicopathological features of mixed epithelial and stromal tumor of the kidney(MESTK). METHODSúClinical and pathological characteristics of one case of MESTK was stujdied. RESULTSúA case of MESTK which uncommonly occurred in a 16-year old adolescent male presented with dysuria and a large mass in the right renal region without a history of estrogen/progestogen treatment and/or obesity or urogenital surgery. Radiology revealed a large cystic/solid mass within the right kidney. Grossly, it was well demarcated and had a solid and cystic appearance on sectioning. Microscopically, the tumor was composed of a mixture of stromal and epithelial components. The epithelial component was composed of flat to columnar cells forming glands or tubules. The stromal components essentially consisted of bland, loosely packed spindle cells in an edematous and myxoid background. In some areas, there were smooth muscle cells forming bands and fascicles but no ovarian-type stroma was present. Immunohistochemical staining revealed that the epithelial components were positive for AE1/AE3 and focally positive for estrogen receptor (ER),progesterone receptor(PR), CD10 and Vimentin, whereas the stromal components were positive for ER, PR, Desmin and smooth muscle actin(SMA). Both epithelial and stromal components were negative for HMB-45, S-100ìalpha-inhibin and WT-T. Five months after resection, the patient was well without evidence of recurrence. CONCLUSIONúMESTK occurred in a pubertal male, as in the current case, supports the hypothesis that proliferation of remnants of the primitive mesenchyme in the kidney in situation of sex-steroid abnormity may play an important role in the pathogenesis of male MESTK.