[摘 要] 目的：探讨微囊性附属器癌（microcystic adnexal carcinoma，MAC）患者的临床病理特征，以提高对该病的诊断水平。方法：观察1例MAC患者的临床表现、影像学特点，分析手术标本病理形态特征及免疫组织化学表型，并结合文献进行探讨。结果：患者为老年男性，临床表现为腋下肿物伴有疼痛；CT示团片状稍低密度软组织影，增强见不均匀强化；病理示肿瘤细胞呈条索、细胞簇及腺样结构，异型性显著；免疫组化显示瘤细胞AEI／AE3，CK19和EMA阳性染色。结论：MAC是一种低度恶性肿瘤;手术不易彻底切除，复发率较高；对于活检的标本极易误诊，明确诊断依赖手术切除标本。

[Abstract] Objective To investigate the clinicopathologic characteristics of microcystic adnexal carcinoma (MAC) for improving the diagnosis. Methods One case of MAC was observed for its clinical symptoms, imaging features, analysising pathological characteristics and immunohistochemical phenotypes of surgical specimens, and also reviewed of relevant literatures. Results The main clinical manifestation of this old male patient was characterized by axillary mass with pain. Chest CT was showed the soft tissue image of a slightly lower density of the mass, and unevenly consolidated by the enhancement of the group. The pathological changes of tumor cells, cell clusters and adenoid structures, are significant. AE3 / AEI, CK19 and EMA positive staining of tumor cells ware demonstrated by immunohistochemistry. Conclusions MAC is a low-grade malignancy. The operation is not easy to be completely removed, and has higher recurrence rate. It is easy to be misdiagnosed for biopsy, and depends on surgical resection specimen to defininte diagnosis.