Wooff J C, Trites J R, Walsh N M G, Bullock M J
Department of Pathology, Capital District Health Authority, Halifax, NS, Canada.
Am J Dermatopathol. 2010 Aug;32(6):614-7. doi: 10.1097/DAD.0b013e3181cd3158.
Merkel cell carcinoma (MCC) is a rare aggressive primary cutaneous neuroendocrine neoplasm with a high rate of recurrence and metastasis. We report a case of a 94-year-old woman who experienced complete spontaneous regression of metastatic MCC. Nine months after complete excision of the primary MCC on her left eyebrow, metastatic MCC was confirmed with a fine-needle aspiration of a 4-cm mass on the left side of her neck. Three months later the mass had reduced in size to 2 cm and a neck dissection was performed. Her submandibular gland, thoracic duct and 25 lymph nodes were negative for MCC. Two of the lymph nodes, the larger measuring 1.3 cm, contained extensive amounts of fibrosis, with accumulation of macrophages and other chronic inflammatory cells. The literature documents 6 similar cases of complete spontaneous regression of metastatic MCC. The mechanism for regression is not well understood and is thought to involve T-cell-mediated immune response and apoptosis.
默克尔细胞癌（MCC）是一种罕见的侵袭性原发性皮肤神经内分泌肿瘤，复发和转移率很高。我们报告一例94岁女性转移性MCC完全自发消退的病例。在她左侧眉毛处的原发性MCC完全切除9个月后，通过对左侧颈部一个4厘米肿块进行细针穿刺确诊为转移性MCC。三个月后，肿块缩小至2厘米，并进行了颈部清扫术。她的下颌下腺、胸导管和25个淋巴结均未发现MCC。其中两个淋巴结，较大的一个为1.3厘米，含有大量纤维化组织，伴有巨噬细胞和其他慢性炎症细胞的积聚。文献记载了6例转移性MCC完全自发消退的类似病例。消退机制尚不完全清楚，认为与T细胞介导的免疫反应和细胞凋亡有关。
