Xia Qiu-Yuan, Wang Xiao-Tong, Zhan Xue-Mei, Tan Xiao, Chen Hao, Liu Yi, Shi Shan-Shan, Wang Xuan, Wei Xue, Ye Sheng-Bing, Li Rui, Ma Heng-Hui, Lu Zhen-Feng, Zhou Xiao-Jun, Rao Qiu
*Department of Pathology, Nanjing Jinling Hospital, Nanjing University School of Medicine, Nanjing †Department of Pathology, Linyi People's Hospital, Linyi ‡Department of Pathology, First People's Hospital of Lianyungang, Lianyungang, China.
Am J Surg Pathol. 2017 May;41(5):663-676. doi: 10.1097/PAS.0000000000000837.
Xp11 translocation renal cell carcinomas (RCC) are characterized by several different translocations involving the TFE3 gene. Tumors with different specific gene fusions may have different clinicopathologic manifestations. Only 3 RBM10-TFE3 RCCs have been reported to date. Here, we added 4 cases of this rare type of tumors with clinicopathologic, immunohistochemical, molecular, and ultrastructural analyses. Most tumors had similar patterns with mixed architectures as follows: acinar, tubular and papillary patterns of epithelioid cells combined with sheets of small cells with "pseudorosette-like" architectures, mimicking the typical morphology of t(6;11) RCC. Cytoplasmic vacuolization, nuclear groove, and psammoma bodies were observed in most cases. Immunohistochemically, all 4 cases demonstrated moderate to strong immunoreactivity for TFE3, Cathepsin K, CD10, Ksp-cadherin, E-cadherin, P504S, RCC marker, PAX8 and vimentin, whereas negativity for TFEB, HMB45, and CK7. CKpan and Melan-A were at least focally expressed. The antibody to Ki-67 showed labeling of 3% to 8% (mean, 5%) of tumor cell nuclei. ;Of interest, several immunostainings demonstrated expression discrepancy in different histology patterns. RBM10-TFE3 fusion transcripts were identified in all cases by reverse transcription-polymerase chain reaction. By fluorescence in situ hybridization, all 4 cases showed unusual split signals with a distance <1 signal diameter (co-localized or subtle split signals) and usually had false-negative results. We also observed ultrastructures, including melanin pigment, nuclear groove, numerous glycogens, mitochondrion with areas of high electron density material, basement membrane material, and cell junctions with poor development. All 4 patients were alive with no evidence of recurrent disease. Our report adds to the known data regarding RBM10-TFE3 RCC.
Xp11易位性肾细胞癌（RCC）的特征是涉及TFE3基因的几种不同易位。具有不同特定基因融合的肿瘤可能具有不同的临床病理表现。迄今为止，仅报道了3例RBM10-TFE3 RCC。在此，我们增加了4例这种罕见类型肿瘤的临床病理、免疫组化、分子和超微结构分析。大多数肿瘤具有相似的混合结构模式如下：上皮样细胞的腺泡状、管状和乳头状模式与具有“假菊形团样”结构的小细胞片相结合，模仿t(6;11) RCC的典型形态。大多数病例中观察到细胞质空泡化、核沟和砂粒体。免疫组化方面，所有4例对TFE3、组织蛋白酶K、CD10、Ksp-钙黏蛋白、E-钙黏蛋白、P504S、RCC标志物、PAX8和波形蛋白呈中度至强免疫反应性，而对TFEB、HMB45和CK7呈阴性。细胞角蛋白广谱和Melan-A至少局灶性表达。Ki-67抗体显示肿瘤细胞核标记率为3%至8%（平均5%）。有趣的是，几种免疫染色在不同组织学模式中显示出表达差异。通过逆转录聚合酶链反应在所有病例中均鉴定出RBM10-TFE3融合转录本。通过荧光原位杂交，所有4例均显示异常分裂信号，距离<1个信号直径（共定位或细微分裂信号）且通常呈假阴性结果。我们还观察到超微结构，包括黑色素、核沟、大量糖原、具有高电子密度物质区域的线粒体、基底膜物质以及发育不良的细胞连接。所有4例患者均存活，无复发疾病迹象。我们的报告增加了关于RBM10-TFE3 RCC的已知数据。
