A case of pseudomesotheliomatous carcinoma of the lung

Abstract

Pseudomesotheliomatous carcinoma of the lung (PMCL) is characterized by marked pleural extension resembling malignant mesothelioma, and has been confirmed histologically as a peripheral lung cancer. We report a rare case of PMCL in a 65-year-old man. The patient had complained of dyspnea and a chest roentgenogram showed right massive pleural effusion. He had histories of smoking and asbestos exposure. Computed tomography (CT) of the chest revealed diffuse irregular pleural thickening. Pleural tissue sampling was performed by video-assisted thoracoscopic surgery (VATS) using a semirigid thoracoscope. At the operation, tumor was found to have spread along the right pleural surface, which was irregularly thickened. Histochemically and immunohistochemically, the tumor was composed of adenocarcinoma ceUs positive for CEA and TTF-1, but negative for calretinin, so we finally diagnosed PMCL. In this case chemotherapy using paclitaxel and carboplatin was largely effective. We considered that histological examination is needed for a diagnosis of PMCL in a case of malignant pleural effusion with pleural thickness, and that VATS is probably the best option for this purpose.