Wang Zhi-Hui, Wang Xing-Chun, Xue Mei
Department of Pathology, Linyi Oncology Hospital, Linyi, Shandong 276000, PR China.
Chin J Cancer. 2010 Feb;29(2):212-6. doi: 10.5732/cjc.009.10339.
Primary renal synovial sarcoma is rare and might be misdiagnosed as another renal tumor. This study demonstrates the clinicopathologic and immunohistochemical features, differential diagnosis, and prognosis of such tumors.
Histologic slides and clinical data were reviewed for 4 patients with primary renal synovial sarcoma and immunohistochemical staining was performed. Molecular analysis was performed on 2 cases to demonstrate the presence of the SYT-SSX gene fusion transcripts by reverse transcriptase polymerase chain reaction (RT-PCR).
The patients were 2 women and 2 men aged from 32 to 48 years. The tumors were 10.0-15.0 cm in diameter, grey-white and solid, and hemorrhage or necrosis was observed. Microscopically, the tumors consisted of mitotically active, monomorphic plump spindle cells with indistinct cell borders growing in short, intersecting fascicles. Hypocellular myxoid areas and a prominent hemangiopericytomatous pattern were present in all cases. The average mitotic rate was 5-8 mitoses/10 high-power fields. Hemorrhage and tumor necrosis were easily found. Scattered small cysts lined with flat, cuboidal, or hobnailed epithelia were found in 3 cases. Tumor cells are immunoreactive for Vimentin (4/4), Bcl-2 (4/4), CD99 (4/4), and CD56 (3/4), and focally for EMA (3/4) and Cytokeratin (3/4). SYT-SSX1 gene fusion was detected in the 2 cases in which RT-PCR analysis was performed. One patient had tumor metastasis to the lung 6 months after surgery and died 5 months later. Multiple metastasis to the liver occurred in one patient and the patient died 13 months after the initial surgery. The other 2 patients had tumors recur at 8 and 15 months and died at 18 and 21 months, respectively, after the initial operation.
Primary renal synovial sarcoma is rare, with poor prognosis, characterized by SYT-SSX gene fusion, and needs to be differentiated from other renal sarcomas.
原发性肾滑膜肉瘤罕见，可能被误诊为其他肾脏肿瘤。本研究阐述了此类肿瘤的临床病理、免疫组化特征、鉴别诊断及预后情况。
回顾4例原发性肾滑膜肉瘤患者的组织学切片及临床资料，并进行免疫组化染色。对其中2例进行分子分析，通过逆转录聚合酶链反应（RT-PCR）检测SYT-SSX基因融合转录本的存在情况。
患者为2名女性和2名男性，年龄32至48岁。肿瘤直径为10.0 - 15.0 cm，灰白色，质地坚实，可见出血或坏死。显微镜下，肿瘤由有丝分裂活跃、形态单一的丰满梭形细胞组成，细胞边界不清，呈短束状交叉生长。所有病例均有细胞稀少的黏液样区域及显著的血管外皮细胞瘤样结构。平均有丝分裂率为5 - 8个/10个高倍视野。易见出血及肿瘤坏死。3例可见散在的小囊肿，内衬扁平、立方或鞋钉样上皮。肿瘤细胞对波形蛋白（4/4）、Bcl-2（4/4）、CD99（4/4）和CD56（3/4）呈免疫反应，部分对EMA（3/4）和细胞角蛋白（3/4）呈免疫反应。在进行RT-PCR分析的2例中检测到SYT-SSX1基因融合。1例患者术后6个月发生肺转移，5个月后死亡。1例患者发生肝脏多发转移，初次手术后13个月死亡。另外2例患者分别在初次手术后8个月和15个月肿瘤复发，分别于18个月和21个月死亡。
原发性肾滑膜肉瘤罕见，预后差，以SYT-SSX基因融合为特征，需与其他肾肉瘤相鉴别。
