Middle Mediastinal Thymoma

Thymoma is a common neoplasm in the anterior mediastinum but rarely arises from the middle mediastinum. We report 3 patients with thymoma that arose from the middle mediastinum. Surgical resections were performed with dissection of the azygos vein, which led to safe separation of the tumors from mediastinal structures. Although rare, thymoma should be included in the differential diagnosis for middle mediastinal tumors.