Yang X J, Lecksell K, Gaudin P, Epstein J I
Department of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
Am J Surg Pathol. 1999 Feb;23(2):147-52. doi: 10.1097/00000478-199902000-00002.
Immunohistochemistry with antibodies for high-molecular-weight cytokeratin labels basal cells and is used as an ancillary study in diagnosing prostate carcinoma, which reportedly lacks expression of high-molecular-weight cytokeratin. A recent report questioned the specificity of this marker, describing immunopositivity for high-molecular-weight cytokeratin in a small series of metastatic prostate cancer. We have also noted rare cases of prostate lesions on biopsy with typical histological features of adenocarcinoma showing immunopositivity for high-molecular-weight cytokeratin, either in tumor cells or in patchy cells with the morphology of basal cells. In some of these cases, it was difficult to distinguish cancer from out-pouching of high-grade prostatic intraepithelial neoplasia. To investigate whether prostate cancer cells express high-molecular-weight cytokeratin, we studied 100 cases of metastatic prostate carcinoma and 10 cases of prostate cancer invading the seminal vesicles from surgical specimens. Metastatic sites included regional lymph nodes (n = 67), bone (n = 19), and miscellaneous (n = 14). Cases with any positivity for high-molecular-weight cytokeratin antibody (34betaE12) were verified as being of prostatic origin with immunohistochemistry for prostate-specific antigen and prostate-specific acid phosphatase. Only four cases were detected positive for high-molecular-weight cytokeratin. In two cases (one metastasis, one seminal vesicle invasion) there was weakly diffuse positivity above background level. Two metastases in lymph nodes showed scattered strong staining of clusters of tumor cells, which represented <0.2% of tumor cells in the metastatic deposits. These positive cells did not have the morphology of basal cells. We conclude that prostate cancer, even high grade, only rarely expresses high-molecular-weight cytokeratin. This marker remains a very useful adjunct in the diagnosis of prostate cancer.
使用高分子量细胞角蛋白抗体进行免疫组织化学可标记基底细胞，并用作诊断前列腺癌的辅助研究，据报道前列腺癌缺乏高分子量细胞角蛋白的表达。最近有报告对该标志物的特异性提出质疑，描述了一小系列转移性前列腺癌中高分子量细胞角蛋白的免疫阳性情况。我们也注意到，在活检的前列腺病变罕见病例中，具有腺癌典型组织学特征的病变在肿瘤细胞或具有基底细胞形态的散在细胞中显示出高分子量细胞角蛋白的免疫阳性。在其中一些病例中，很难将癌与高级别前列腺上皮内瘤变的憩室区分开来。为了研究前列腺癌细胞是否表达高分子量细胞角蛋白，我们研究了100例转移性前列腺癌病例和10例手术标本中侵犯精囊的前列腺癌病例。转移部位包括区域淋巴结（n = 67）﹑骨（n = 19）和其他部位（n = 14）。对高分子量细胞角蛋白抗体（34βE12）呈任何阳性的病例，通过前列腺特异性抗原和前列腺特异性酸性磷酸酶的免疫组织化学鉴定为前列腺来源。仅检测到4例高分子量细胞角蛋白阳性。在2例（1例转移，1例精囊侵犯）中，有弱弥漫性阳性高于背景水平。淋巴结中的2处转移显示肿瘤细胞簇散在强染色，这些肿瘤细胞簇在转移灶中占肿瘤细胞的<0.2%。这些阳性细胞不具有基底细胞的形态。我们得出结论，前列腺癌，即使是高级别，也仅极少表达高分子量细胞角蛋白。该标志物在前列腺癌的诊断中仍然是非常有用的辅助手段。
