[Horner syndrome due to mediastinal neurinoma--a case report].

Horner syndrome due to mediastinal neurinoma has been reported rare cases so far. We experienced a 55-year-old woman who developed Hornor syndrome due to mediastinal neurinoma and the patient received operation with no major complication. She was admitted to our hospital because of the left shoulder pain and the dilatation of the mediastinum on chest X-ray. She was found to have the left mild ptosis and CT scan showed left upper mediastinal tumor (12 cm in diameter) with tracheal compression. Aortography showed a 8.6 cm tumor stein and lower deviation of aortic arch. The feeding artery was branch of thyrocervical artery. Mediastinal neurinema was found by biopsy. During the operation, we found the origin was the left sympathetic nerve. The post operative course was uneventful however horner syndrome was progressed due to radical resection of the tumor.