Thoracoscopic resection of middle mediastinal noninvasive thymoma: report of a case.

We performed thoracoscopic resection of a middle mediastinal noninvasive thymoma in a 69-year-old woman. Chest computed tomography on admission showed a tumor, 75 x 48 x 32 mm in size, and pathological examination revealed a spindle-cell, noninvasive thymoma, of type A according to the World Health Organization classification, and stage I according to the Masaoka staging system. Thymomas are prone to ectopic occurrence, and should be considered in the differential diagnosis of middle mediastinum tumors.