A Case of Malignant Pleural Mesothelioma with Cystic Formation in the Mediastinum

Abstract

A case of malignant pleural mesothelioma with cystic formation in the mediastinum is reported. In April 1995, a 77-year-old woman was admitted because of persistent nonproductive cough. Chest radiographs and CT revealed pleural effusions, a rimenhanced cystic tumor in the mediastinum, an oval tumor of the right posterior chest wall, and severe compression of the trachea by the tumor. The tumor cells were biphasic. Cytoplasm of tumor cells stained by Alcian blue but the staining disappeared following hyaluronidase digestion. Immunohistochemical examinations showed positive staining for keratin but not for CEA. Based on these findings, malignant pleural mesothelioma of the biphasic type was diagnosed. The chest radiographs and CT of the case showed unique images. In patients with cystic lesions of the mediastinum, malignant mesothelioma should be considered in the differential diagnosis.