Mediastinal neurofibroma originating from the left intrathoracic phrenic nerve: report of a case.

We report a case of mediastinal neurofibroma originating from the left phrenic nerve in a 42-year-old woman who was referred to us after a routine chest X-ray showed a smooth, round abnormal shadow in the left middle lung field adjacent to the heart. We resected a 25 x 20 x 20-mm tumor by video-assisted thoracic surgery. Histopathological examination confirmed that the lesion was a mediastinal neurofibroma originating from the left phrenic nerve without von Recklinghausen's disease. Neurogenic mediastinal tumors originating from the phrenic nerve are very rare, and to the best of our knowledge, no other case of a mediastinal neurofibroma originating from the phrenic nerve in a patient without von Recklinghausen's disease has ever been reported.