Department of Surgical Pathology, Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, Spain.
Pathol Oncol Res. 2011 Sep;17(3):519-23. doi: 10.1007/s12253-010-9341-z. Epub 2011 Jan 4.
Small cell carcinoma of the bladder is an uncommon and rather aggressive bladder tumor, representing less than 1% of all vesical tumors. Small cell carcinoma of different organs has been shown to express markers of neuroendocrine differentiation, and also thyroid transcription factor 1 (TTF-1). TTF-1 is a transcription factor and its expression has been shown mainly in pulmonary small cell carcinomas and adenocarcinomas and in thyroid tumors. Although it was initially proposed as a useful marker to delineate the origin of metastatic adenocarcinomas from the lung, its expression is being increasingly reported in tumors from different origins. The goal of this review is to analyse the immunohistochemical profile of small cell carcinoma of the bladder and to compare it to classical urothelial cell carcinomas. With this aim we have reviewed the small cell bladder carcinomas diagnosed in a single tertiary hospital in Madrid (Fundación Jiménez Díaz) in the last 12 years. We have found 6 pure small cell carcinomas and performed a wide panel of immunohistochemistry, including cytokeratins 7 and 20, enolase, chromogranin, synaptophysin, CD56 and TTF-1 to these tumors and also to 30 high grade urothelial cell carcinomas of usual type. Only one of our small cell carcinoma cases showed positivity for TTF-1, while five expressed CD56 and four neuron-specific enolase. None of our cases expressed cytokeratin 20 or 7. To our surprise we found a case of conventional urothelial cell carcinoma expressing focally TTF-1. These results are in accordance with the current literature, although our rate of TTF-1 expression (16.6%) is on the low end of the spectrum.
膀胱小细胞癌是一种罕见且侵袭性较强的膀胱肿瘤，占所有膀胱肿瘤的比例不到 1%。不同器官的小细胞癌已被证明表达神经内分泌分化标志物，如甲状腺转录因子 1（TTF-1）。TTF-1 是一种转录因子，其表达主要见于肺小细胞癌和腺癌以及甲状腺肿瘤。尽管最初被提出作为区分肺转移性腺癌来源的有用标志物，但它的表达在不同来源的肿瘤中越来越多地被报道。本综述的目的是分析膀胱小细胞癌的免疫组织化学特征，并将其与经典的尿路上皮细胞癌进行比较。为此，我们回顾了在马德里（金米尼兹-迪亚兹基金会）的一家三级医院诊断的 12 年来的膀胱小细胞癌病例。我们发现了 6 例纯小细胞癌，并对这些肿瘤和 30 例常见型高级别尿路上皮癌进行了广泛的免疫组织化学检测，包括细胞角蛋白 7 和 20、烯醇酶、嗜铬粒蛋白、突触素、CD56 和 TTF-1。我们的小细胞癌病例中只有 1 例显示 TTF-1 阳性，5 例表达 CD56，4 例表达神经元特异性烯醇酶。我们的病例均未表达细胞角蛋白 20 或 7。令我们惊讶的是，我们发现了 1 例常规尿路上皮细胞癌局灶性表达 TTF-1。这些结果与目前的文献一致，尽管我们的 TTF-1 表达率（16.6%）处于较低水平。
