Potentially disseminated solitary fibrous tumor of the pleura: a case report

We report a case involving a female patient with frequent relapse, pleural dissemination, and port site recurrence (PSR) of a pleural solitary fibrous tumor (SFT). At the age of 55 years, she underwent tumor resection via video-assisted thoracoscopic surgery (VATS). The tumor arose from the mediastinal pleura; it was 7 cm in diameter and well demarcated. Histological examination showed neither hemorrhage nor necrosis, but moderate cellularity was present, and the Ki-67 labeling index was 15%. Despite complete resection, the tumor relapsed in the ipsilateral thoracic cavity 3 years postoperatively, and thoracoscopic complete tumor resection was performed; however, pleural lavage cytology (PLC) showed the presence of tumor cells. Multiple pleural dissemination and PSR developed 7 years after the initial surgery. The port site recurrent tumor was resected with the intercostal muscle via VATS. This case illustrates that a SFT may disseminate despite the fact that histological examination shows no evidence of malignancy.