Hemangiopericytoma of the trachea.

Malignant neoplasms of the trachea are rare lesions, with no more than 400 cases documented in the literature. Only three tracheal hemangiopericytomas have been reported. We present the fourth case of such a tumour occurring in the trachea. After the first surgical resection the tumour recurred twice in a period of 10 months. The last cervicotomy performed for local recurrence showed wide cervical and mediastinal involvement of the tumour, not resectable surgically. Emphasis is placed on the surgical, pathologic and ultramicroscopic findings.