Department of Pathology and Medical Research Institute, Pusan National University Hospital, Busan, Republic of Korea.
Pathol Res Pract. 2012 Dec 15;208(12):741-5. doi: 10.1016/j.prp.2012.09.005. Epub 2012 Oct 22.
Mediastinal teratoma with malignant transformation (TMT) is a very rare condition. A 44-year-old man presented with a large cystic mass of the anterior mediastinum. The tumor was surgically removed. The cystic mass was well demarcated, with an irregularly thickened wall. Histologically, the cystic wall was mainly lined by non-ciliated columnar epithelium and focally by squamous epithelium. A nodular part of the cystic wall revealed well-differentiated adenocarcinoma composed of tubulopapillary structures. Deep in the nodular tissue, neoplastic glands merged into undifferentiated sarcomatous cells. Immunohistochemically, CK7, CK19, and smad-4 were strongly and diffusely positive in adenocarcinoma. CD10 was focally positive on the luminal surface of the glands, and MUC5AC was also focally positive. TTF-1, cdx-2, and CK20 were negative in the adenocarinoma. Sarcomatous area showed diffuse strong positivity for vimentin, but was negative for the aforementioned epithelial markers. About 10 months postoperatively, a left pleural effusion had developed with multiple pleural nodules on computed tomography scan of the chest. The cytologic diagnosis from pleural fluid was metastatic adenocarcinoma. To our knowledge, in the English literature, this is the first case of adenocarcinoma with sarcomatous transformation that has developed in a mature cystic teratoma of the mediastinum and shows pleural metastasis.
纵隔生殖细胞瘤恶变（TMT）是一种非常罕见的情况。一名 44 岁男性因前纵隔大囊性肿块就诊。肿瘤被手术切除。囊性肿块边界清楚，壁不规则增厚。组织学上，囊性壁主要由非纤毛柱状上皮和局灶性鳞状上皮衬里。囊性壁的一个结节部分显示出分化良好的腺癌，由管状乳头状结构组成。在结节组织的深处，肿瘤腺体融合为未分化的肉瘤样细胞。免疫组化染色显示，腺癌中 CK7、CK19 和 smad-4 强阳性且弥漫阳性。CD10 在腺体的腔面局灶性阳性，MUC5AC 也局灶性阳性。TTF-1、cdx-2 和 CK20 在腺癌中阴性。肉瘤样区域弥漫强阳性表达波形蛋白，但上述上皮标志物均为阴性。术后约 10 个月，患者出现左侧胸腔积液，胸部 CT 扫描显示多个胸膜结节。胸腔积液的细胞学诊断为转移性腺癌。据我们所知，在英文文献中，这是首例发生在成熟囊性纵隔生殖细胞瘤中的腺癌伴肉瘤样转化，并出现胸膜转移的病例。
