Clinical experience with malignant pheochromocytomas.

In a 30 year period at Vanderbilt University Hospital, the affiliated Nashville General Hospital and the Nashville Veterans Administration Hospital, 64 patients with pheochromocytoma have been observed. In eight of these, the tumor proved to be malignant. Retrospective review of biologic characteristics of pheochromocytomas in this series included clinical, diagnostic imaging, chemical and histopathologic data. Aside from presence of distant metastases, none of these features had predictive value in indicating the biologic malignant nature of the primary tumor. One patient has been cured by radical surgical resection for 16 years. Three others have died with metastatic tumor and three patients are alive with metastatic tumor.