Kawahara Akihiko, Harada Hiroshi, Yokoyama Toshiro, Kage Masayoshi
Department of Pathology, Kurume University Hospital, Kurume, Japan.
Diagn Cytopathol. 2004 Apr;30(4):280-3. doi: 10.1002/dc.20021.
Epithelial-myoepithelial carcinoma (EMC) is a rare low-grade carcinoma occurring most frequently in the parotid gland. Most EMCs consist of two cell types that typically form double-layered ductal structures. However, occasionally EMC presents predominantly clear myoepithelial cells. A 34-year-old man visited in August 1993 and was diagnosed as having clear-cell carcinoma. The tumor was curatively resected. However, in the following 5 years, recurrence developed a total of five times. The imprint cytological feature of the recurrence at the third time showed monophasic clear cells in sheet clusters with overlapping. Most of the clear tumor cells presented an expression to alpha-smooth muscle actin (SMA). The imprint cytological feature of the recurrence at the fifth time showed increase of nuclear atypia with coarse chromatin patterns and large nucleoli. In addition to cytological findings, the cytological diagnosis of EMC with predominant clear myoepithelial cells requires a definite expression to SMA.
上皮-肌上皮癌（EMC）是一种罕见的低级别癌，最常发生于腮腺。大多数EMC由两种细胞类型组成，通常形成双层导管结构。然而，EMC偶尔主要表现为透明肌上皮细胞。一名34岁男性于1993年8月就诊，被诊断为透明细胞癌。肿瘤被根治性切除。然而，在接下来的5年里，共复发了5次。第三次复发时的印片细胞学特征显示单相透明细胞呈片状聚集且相互重叠。大多数透明肿瘤细胞表达α-平滑肌肌动蛋白（SMA）。第五次复发时的印片细胞学特征显示核异型性增加，染色质粗糙，核仁大。除细胞学表现外，以透明肌上皮细胞为主的EMC的细胞学诊断需要SMA有明确表达。
