Department of Pathology, The University of Texas MD Anderson Cancer Center, 1515 Holcomb Blvd, Houston, TX, 77030, USA.
Department of Translational and Molecular Pathology, The University of Texas MD Anderson Cancer Center, 1515 Holcomb Blvd, Houston, TX, 77030, USA.
Mod Pathol. 2020 Jan;33(Suppl 1):42-55. doi: 10.1038/s41379-019-0394-6. Epub 2019 Nov 1.
Merkel cell carcinoma (MCC) is a high grade primary cutaneous neuroendocrine carcinoma and is among the most aggressive cutaneous malignancies. The rising incidence of MCC, together with its often rapidly aggressive course, underscore a critical need to recognize the histopathologic and the immunohistochemical features that inform its accurate diagnosis. In the current review, we summarize the current state of knowledge regarding the accurate diagnosis of MCC and the exclusion of other entities in the differential diagnosis. We provide a comprehensive review of genomic studies that identified the molecular-genetic drivers of MCC as well as a summary of studies identifying prognostic biomarkers that can facilitate risk stratification. Importantly, Merkel cell polyomavirus (MCPyV) appears to be causative in most cases of MCC and represents both a diagnostic and prognostic marker. Finally, as staging of MCC has undergone critical refinements with the introduction of the 8th Edition of the American Joint Committee on Cancer staging system, we provide an update on MCC staging. In particular, the prognostic significance of the sentinel lymph node (SLN) in MCC necessitates a systematic approach to its evaluation and diagnosis to ensure accurate and consistent risk stratification for patients, and we therefore provide a comprehensive overview of SLN evaluation in MCC. Finally, the intimate relationship between MCC and the integrity of the host immune system has led to paradigm-shifting therapeutic advances with the successful application of immune checkpoint blockade to treat patients with advanced disease, and we therefore summarize those studies and the correlative studies in which predictive biomarkers have been identified.
默克尔细胞癌（Merkel cell carcinoma，MCC）是一种高级别原发性皮肤神经内分泌癌，是最具侵袭性的皮肤恶性肿瘤之一。MCC 的发病率不断上升，且其病程往往迅速恶化，这突显了准确识别其组织病理学和免疫组织化学特征以进行准确诊断的重要性。在本次综述中，我们总结了 MCC 准确诊断和鉴别诊断中排除其他疾病的最新知识。我们全面回顾了确定 MCC 分子遗传驱动因素的基因组研究，以及确定有助于风险分层的预后生物标志物的研究。重要的是，默克尔细胞多瘤病毒（Merkel cell polyomavirus，MCPyV）似乎是大多数 MCC 的致病因素，它既是诊断标志物也是预后标志物。最后，随着第 8 版美国癌症联合委员会（American Joint Committee on Cancer，AJCC）分期系统的引入，MCC 的分期发生了重大改进，我们提供了 MCC 分期的最新信息。特别是，前哨淋巴结（sentinel lymph node，SLN）在 MCC 中的预后意义需要对其进行系统评估和诊断，以确保对患者进行准确和一致的风险分层，因此我们全面概述了 MCC 中 SLN 的评估。最后，MCC 与宿主免疫系统完整性之间的密切关系导致了治疗方法的重大变革，免疫检查点阻断成功应用于治疗晚期疾病的患者，因此我们总结了这些研究以及确定了预测生物标志物的相关研究。
