Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL 32610, USA.
Hum Pathol. 2011 Oct;42(10):1554-61. doi: 10.1016/j.humpath.2010.12.019. Epub 2011 Apr 14.
Primary renal carcinoid tumors are rare neoplasms. Because of the rarity of these neoplasms, clinicopathologic and immunohistochemical characteristics have not been fully characterized. Immunohistochemistry for renal cell lineage transcription factors, such as paired box gene 2 and paired box gene 8, has not been studied in renal carcinoid tumors and may be useful in demonstrating nephrogenic differentiation. We studied the clinical, morphological, and immunohistochemical features in 9 primary renal carcinoid tumors from multiple institutions with particular emphasis on immunohistochemical findings, in particular, expression of paired box gene 2 and paired box gene 8. All 9 cases expressed at least 1 neuroendocrine marker (CD56, synaptophysin, chromogranin). The renal-associated (paired box gene 2/paired box gene 8), gastrointestinal (caudal-related homeobox-2), and pulmonary/thyroid (thyroid transcription factor-1) transcription factors were not expressed in renal carcinoids (0/9). Of interest, CD99 was expressed in 8 of 9 cases, with the one negative case representing an atypical carcinoid. Perinephric extension and nodal and distant metastases are common. The absence of expression of paired box gene 2 and paired box gene 8, although not conclusive, supports the theory that these are derived from nonnephrogenic elements. CD99 was expressed in almost all cases (8/9); recognition of this could prevent misdiagnosis of a renal primitive neuroectodermal tumor.
原发性肾类癌肿瘤是罕见的肿瘤。由于这些肿瘤的罕见性，其临床病理和免疫组织化学特征尚未完全确定。肾细胞谱系转录因子（如配对盒基因 2 和配对盒基因 8）的免疫组织化学在肾类癌肿瘤中尚未得到研究，可能有助于显示肾源性分化。我们研究了来自多个机构的 9 例原发性肾类癌肿瘤的临床、形态学和免疫组织化学特征，特别强调了免疫组织化学发现，特别是配对盒基因 2 和配对盒基因 8 的表达。所有 9 例均至少表达 1 种神经内分泌标志物（CD56、突触素、嗜铬粒蛋白）。肾相关（配对盒基因 2/配对盒基因 8）、胃肠道（尾相关同源盒-2）和肺/甲状腺（甲状腺转录因子-1）转录因子在肾类癌中均不表达（0/9）。有趣的是，8/9 例 CD99 表达，1 例不表达的为非典型类癌。肾周延伸、淋巴结和远处转移很常见。配对盒基因 2 和配对盒基因 8 的表达缺失，尽管不具有结论性，但支持这些肿瘤源自非肾源性成分的理论。几乎所有病例（8/9）均表达 CD99；认识到这一点可以防止误诊为肾原始神经外胚层肿瘤。
