[Solitary Fibrous Tumor Originating from the Visceral Pleura Presenting an Extrapleural Sign;Report of a Case].

We report a case of solitary fibrous tumor (SFT) originating from the visceral pleura, which presented an extrapleural sign on chest computed tomography (CT) and magnetic resonance imaging (MRI). A 44-year-old woman presented at our hospital for a growing mass visible in chest X-rays. Chest CT and MRI detected a 27×12 mm lesion on the intrathoracic side of the right 3rd intercostal space. The extrapleural signs strongly suggested the tumor to be chest wall origin. However, the tumor was found to be pedunculate with an umbrella-like appearance locating on the visceral pleura of the lung. Histopathological examination demonstrated SFT originating from the visceral pleura.