Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Am J Surg Pathol. 2013 May;37(5):727-33. doi: 10.1097/PAS.0b013e3182793dc2.
OCT4 immunostaining has become an essential resource in diagnosing germ cell neoplasia. OCT4 is a transcription factor with a characteristic nuclear staining pattern specific to germ cell neoplasms. Our institution has observed that paraganglionic tissue consistently displayed intense cytoplasmic staining by utilizing monoclonal OCT4 antibody, and we intended to determine whether OCT4 could provide additional diagnostic utility in adrenal tumors. We used monoclonal and polyclonal OCT4 antibodies for comparison of staining patterns and intensities. Thirty-eight pheochromocytomas (8 metastatic), 22 adrenal cortical carcinomas (2 metastatic), 15 metastatic tumors to the adrenal glands, and 10 normal adrenal glands containing cortical and medullary tissue were immunostained with OCT4. A 4-tier system (0 to 3), for recording intensity and extent of cytoplasmic staining, was used. All 30 primary pheochromocytomas displayed strong and diffuse (3+3) cytoplasmic immunoexpression. Six of 8 metastatic pheochromocytomas showed strong immunoexpression (3+3), whereas the remaining 2 showed moderate intensity (2+3). All 22 adrenal cortical carcinomas, including metastatic cases, were completely negative. Only 2 metastatic tumors to the adrenal gland showed weak, cytoplasmic positivity: a small cell carcinoma and a Merkel cell carcinoma. Controls stained in an appropriate nuclear manner. Immunoelectron microscopy demonstrated the antibody interacting with neurosecretory granules. To our knowledge, the cytoplasmic expression of OCT4 in adrenal medulla and pheochromocytoma has not been specifically studied. The goal of this study is to analyze the immunoreactivity of adrenal cortical carcinoma and pheochromocytoma to OCT4 and determine the sensitivity and specificity of this particular staining pattern and to compare monoclonal and polyclonal antibodies.
OCT4 免疫染色已成为诊断生殖细胞肿瘤的重要手段。OCT4 是一种转录因子，具有特征性的核染色模式，特异性地存在于生殖细胞肿瘤中。我们机构观察到，利用单克隆 OCT4 抗体，副神经节组织始终表现出强烈的细胞质染色，我们试图确定 OCT4 是否可以为肾上腺肿瘤提供额外的诊断效用。我们使用单克隆和多克隆 OCT4 抗体比较染色模式和强度。对 38 例嗜铬细胞瘤（8 例转移）、22 例肾上腺皮质癌（2 例转移）、15 例肾上腺转移瘤和 10 例含有皮质和髓质组织的正常肾上腺进行 OCT4 免疫染色。使用 4 级系统（0 至 3）记录细胞质染色的强度和范围。所有 30 例原发性嗜铬细胞瘤均显示出强烈和弥漫的（3+3）细胞质免疫表达。8 例转移性嗜铬细胞瘤中有 6 例显示强烈的免疫表达（3+3），而其余 2 例显示中度强度（2+3）。包括转移病例在内的所有 22 例肾上腺皮质癌均完全阴性。仅有 2 例肾上腺转移瘤表现出微弱的细胞质阳性：小细胞癌和 Merkel 细胞癌。对照以适当的核方式染色。免疫电子显微镜显示抗体与神经分泌颗粒相互作用。据我们所知，OCT4 在肾上腺髓质和嗜铬细胞瘤中的细胞质表达尚未被专门研究。本研究的目的是分析 OCT4 在肾上腺皮质癌和嗜铬细胞瘤中的免疫反应性，并确定这种特殊染色模式的敏感性和特异性，并比较单克隆和多克隆抗体。
