Ryska A, Kerekes Z, Hovorková E, Barton P
Department of Pathology, Charles University Medical Faculty Hospital, Hradec Králové, Czech Republic.
Pathol Res Pract. 1998;194(6):431-5; discussion 436-8. doi: 10.1016/S0344-0338(98)80034-4.
An extremely rare case of epithelial-myoepithelial carcinoma (EMC) of a lobar bronchus in a 47-year-old female is reported. Grossly, the tumor formed a polypoid mass obstructing the bronchial lumen. Microscopically, it was composed of two cellular types--epithelial cells with eosinophilic cytoplasm and clear myoepithelial cells. Numerous tubules formed by an inner epithelial and outer myoepithelial layer were found. Focally, the tumor showed solid growth of clear cells. Prominent hyalinization of the stroma was found. The nature of the cells was confirmed by positive expression of cytokeratins and epithelial membrane antigen in epithelial cells and vimentin and smooth muscle actin in myoepithelial cells. Differential diagnosis of EMC includes a broad spectrum of salivary gland-type tumors. Furthermore, metastases of clear cell carcinoma of the kidney or thyroid, clear cell ("sugar") tumor of the lung, glandular form of carcinoid, bronchioalveolar adenocarcinoma with myoepithelial cells and pulmonary adenosquamous carcinoma with amyloid-like stroma must be distinguished from EMC. The tumor has neither recurred nor metastasised, a fact supporting the current opinion, that EMC is a tumor of low grade malignancy.
报告了一例极为罕见的47岁女性叶支气管上皮-肌上皮癌（EMC）病例。大体上，肿瘤形成息肉样肿块阻塞支气管腔。显微镜下，它由两种细胞类型组成——具有嗜酸性细胞质的上皮细胞和透明的肌上皮细胞。发现了由内层上皮和外层肌上皮层形成的大量小管。局部可见透明细胞实性生长。间质有明显的玻璃样变。通过上皮细胞中细胞角蛋白和上皮膜抗原以及肌上皮细胞中波形蛋白和平滑肌肌动蛋白的阳性表达证实了细胞的性质。EMC的鉴别诊断包括多种涎腺型肿瘤。此外，肾或甲状腺透明细胞癌转移、肺透明细胞（“糖”）瘤、类癌的腺型、具有肌上皮细胞的细支气管肺泡腺癌以及具有淀粉样间质的肺腺鳞癌必须与EMC相鉴别。该肿瘤既未复发也未转移，这一事实支持了目前的观点，即EMC是一种低级别恶性肿瘤。
