A case of mediastinal mesenchymal tumor with pericytic neoplasm feature that responded to radiation therapy.

Here, we report a case of mediastinal mesenchymal tumor with a pericytic neoplasm feature that responded to radiation therapy. A 43-year-old man visited our hospital with a complaint of esophageal obstruction and chest pain. Chest computed tomography revealed a middle mediastinal tumor and a mesenchymal tumor was diagnosed with a pericytic neoplasm feature by video-assisted thoracoscopic biopsy. The definitive treatment for soft tissue tumor is surgical resection; however, the mediastinal tumor was unresectable because of esophageal and tracheal invasion. Radiation therapy was administered and there was a partial tumor response and 2 years disease-free status. With a review of the literature, we discuss the clinical and pathological characteristics of this rare tumor and its treatment.