Kimura Noriko, Hasegawa Masaru, Hiroshima Kenzo
Department of Diagnostic Pathology, and Department of Clinical Research Pathology Division.
Department of Respiratory Medicine, National Hospital Organization Hakodate Hospital, Hakodate.
Pathol Int. 2018 Feb;68(2):128-132. doi: 10.1111/pin.12623. Epub 2018 Jan 5.
Malignant mesothelioma (MM) with rhabdoid features is an MM variant. Fifteen cases have been reported previously, all of which were combined with other types of MM. Herein, we report an autopsy case of pleural MM with monomorphic rhabdoid features. The patient was a 62-year-old male without a history of asbestos exposure. An autopsy revealed a soft, granular tumor that replaced the entire left pleura and had invaded to the diaphragm and lower lobe of the lung. The tumor cells, which had eosinophilic plump cytoplasm and eccentric nuclei, were loosely cohesive. Immunohistochemistry showed that the cells were diffusely positive for calretinin, D2-40, vimentin, CAM5.2, and AE1/AE3; and negative for WT-1, TTF-1, CK7, CEA, desmin, CD34, BCL-2, S100 protein, and p40. Neither homozygous deletion of p16 nor BAP-1 protein loss was observed. Loss of INI1/BAF47 protein, an indicator of malignant rhabdoid tumor, was observed. Therefore, MM with rhabdoid features was confirmed.
具有横纹肌样特征的恶性间皮瘤（MM）是MM的一种变体。此前已报道过15例，所有病例均合并其他类型的MM。在此，我们报告一例具有单形性横纹肌样特征的胸膜MM尸检病例。患者为62岁男性，无石棉接触史。尸检发现一个柔软的颗粒状肿瘤，取代了整个左胸膜，并侵犯至膈肌和肺下叶。肿瘤细胞具有嗜酸性丰满的细胞质和偏心核，细胞间连接松散。免疫组化显示细胞弥漫性表达钙视网膜蛋白、D2-40、波形蛋白、CAM5.2和AE1/AE3；WT-1、TTF-1、CK7、癌胚抗原、结蛋白、CD34、BCL-2、S100蛋白和p40均为阴性。未观察到p16纯合缺失或BAP-1蛋白缺失。观察到INI1/BAF47蛋白缺失，这是恶性横纹肌样肿瘤的一个指标。因此，确诊为具有横纹肌样特征的MM。
