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[Dumbbell type schwannoma of the posterior mediastinum: a report of two cases with different surgical approaches].

Two cases of dumbbell type schwannoma of the posterior mediastinum are reported. Case 1 involved a 16-year-old man and case 2, a 48-year-old woman. They were asymptomatic, and in both cases an abnormal mass shadow of the left mediastinum was incidentally detected on a routine chest roentogenogram. In these cases, CT and MRI revealed that dumbbell type tumors extended to the spinal canal. The operations were performed with thoracic approach cooperated with a neurosurgeon in case 1 and with combined posterior and thoracic approach cooperated with an orthopedic surgeon in case 2. Histopathologic findings indicated all benign schwannomas. The reported 25 cases in Japan sofar are reviewed.