Wu Karen N, McCue Peter A, Berger Adam, Spiegel Joseph R, Wang Zi-Xuan, Witkiewicz Agnieszka K
Thomas Jefferson University, Philadelphia, PA 19107, USA.
Int J Surg Pathol. 2010 Oct;18(5):342-6. doi: 10.1177/1066896910371638. Epub 2010 May 18.
A 61-year-old woman presented with solitary lymphadenopathy suspicious for lymphoma. An excisional biopsy of a right inguinal lymph node demonstrated metastatic Merkel cell carcinoma (MCC). No skin lesions were detected, but a primary nasopharyngeal mass was identified. A microscopic examination of the nasopharyngeal tumor and the lymph node metastasis showed a monotonous population of small- to intermediate-sized, round blue cells with vesicular nuclei, finely granular and dusty chromatin, and multiple nucleoli. Immunohistochemistry showed perinuclear dot-like staining for cytokeratins AE1/AE3 and CK20. Microscopic appearance and immunohistochemical stains were consistent with MCC. MCC was recently shown to harbor a novel polyomavirus, Merkel cell polyomavirus (MCPyV), in the majority of cases. In this case, MCPyV was detected in the primary tumor and metastasis using polymerase chain reaction and CM2B4 immunohistochemical stain. This is the first report to demonstrate the presence of MCPyV and CM2B4 in a mucosal MCC and its metastasis.
一名61岁女性因孤立性淋巴结病就诊，怀疑为淋巴瘤。对右侧腹股沟淋巴结进行切除活检，结果显示为转移性默克尔细胞癌（MCC）。未检测到皮肤病变，但发现了一个原发性鼻咽肿物。对鼻咽肿瘤和淋巴结转移灶进行显微镜检查，可见一群形态单一的小至中等大小的圆形蓝色细胞，细胞核呈泡状，染色质细颗粒状且有粉尘样外观，并有多个核仁。免疫组化显示细胞角蛋白AE1/AE3和CK20呈核周点状染色。显微镜下表现和免疫组化染色结果与MCC相符。最近研究表明，大多数MCC病例中都携有一种新型多瘤病毒，即默克尔细胞多瘤病毒（MCPyV）。在该病例中，通过聚合酶链反应和CM2B4免疫组化染色在原发性肿瘤和转移灶中检测到了MCPyV。这是首次报道在黏膜MCC及其转移灶中存在MCPyV和CM2B4。
