Du Hexi, Zhou Jun, Xu Lingfan, Yang Cheng, Zhang Li, Liang Chaozhao
Department of Urology, the First Affiliated Hospital of Anhui Medical University and Institute of Urology, Anhui Medical University, Hefei, Anhui, China.
Medicine (Baltimore). 2016 Nov;95(44):e5248. doi: 10.1097/MD.0000000000005248.
Perivascular epithelioid cell tumor (PEComa) is a mesenchymal neoplasm composed of perivascular epithelioid cells with clear to eosinophilic cytoplasm. Pigmented PEComa arising from kidney is extraordinarily rare and sometimes can exhibit aggressive biological behavior.
We present here a rare case of pigmented renal PEComa in a 46-year-old female. The patient had complained of lumbago complicated with nausea and vomiting for 2 weeks and therefore was referred to our department. An enhanced computed scan revealed a 4 × 3 × 3 cm round-like mass in the lower pole of right kidney with inhomogeneous enhancement. The tumor cells immunestained was positive for HMB-45, focally positive for c-Kit (CD117), and negative for vimentin, S-100, AE1/AE3, CK-7, CK-18, CD-10, RCC antigen, CgA, DOG-1, EMA, smooth muscle actin, and synaptophysin. We successfully performed 3-dimensional laparoscopic resection of the neoplasm, which was then diagnosed as pigmented PEComa by postoperative pathology. No further growing lesion or metastasis was observed during a 1-year follow-up.
This case report shows that pigmented renal PEComa is often presented as a renal mass with nonspecific symptoms and imaging features. The gold diagnosis of renal pigmented PEComa is mainly based on the combination of histopathology and immunohistochemistry. Complete resection by 3-dimensional laparoscopic nephron-sparing surgery can be an effective therapeutic management.
血管周上皮样细胞瘤（PEComa）是一种间叶性肿瘤，由具有透明至嗜酸性细胞质的血管周上皮样细胞组成。起源于肾脏的色素性PEComa极为罕见，有时可表现出侵袭性生物学行为。
我们在此报告一例46岁女性的罕见色素性肾PEComa病例。患者因腰痛伴恶心呕吐2周前来就诊，遂转诊至我科。增强计算机断层扫描显示右肾下极有一个4×3×3cm的类圆形肿块，强化不均匀。肿瘤细胞免疫染色HMB-45阳性，c-Kit（CD117）局灶性阳性，波形蛋白、S-100、AE1/AE3、CK-7、CK-18、CD-10、肾细胞癌抗原、嗜铬粒蛋白A、DOG-1、上皮膜抗原、平滑肌肌动蛋白和突触素均为阴性。我们成功地对该肿瘤进行了三维腹腔镜切除术，术后病理诊断为色素性PEComa。在1年的随访中未观察到进一步的病变生长或转移。
本病例报告表明，色素性肾PEComa常表现为具有非特异性症状和影像学特征的肾脏肿块。肾色素性PEComa的金标准诊断主要基于组织病理学和免疫组织化学的结合。通过三维腹腔镜保留肾单位手术完全切除可能是一种有效的治疗方法。
