[A case of localized malignant pleural mesothelioma]

A 74-year-old man was referred to our hospital for examination of an abnormal chest shadow. A chest computed tomography (CT) scan revealed a 5-cm mass attached to the pleura involving the right upper lobe, and a nodule in the right middle lobe. Transbronchial lung biopsy was performed twice, but no definitive diagnosis was achieved. 18-fluorodeoxyglucose positron emission tomography showed abnormal uptake in the chest lesion. Chemotherapy was initiated for advanced-stage lung cancer, but was not effective. Histopathologic and immunohistochemical examinations after CT-guided needle biopsy revealed malignant mesothelioma. The tumor cells were positive for calretinin and thrombomodulin, and negative for CEA, TTF-1, and SP-A. There was local tumor invasion and metastasis in the lung and brain, without diffuse pleural spread. This is a rare and important case of localized malignant mesothelioma pathologically confirmed by biopsy.