Abstract
A chondroma is a common benign cartilaginous tumor. However, a primary soft tissue chondroma of the posterior mediastinum is very rare. We herein report a case involving a 51-year-old man with a posterior mediastinal mass. The mass was dissected by thoracoscopy through the eighth intercostal space. Pathological examination led to a definitive diagnosis of a primary mediastinal chondroma with no criteria of malignancy. Preoperative diagnosis of a posterior mediastinal soft tissue chondroma is not easy because of its rarity and lack of typical features other than calcification. When a posterior mediastinal well-circumscribed soft tissue mass contains calcification and shows no obvious enhancement, the possibility of a soft tissue chondroma should be considered.