YOLK-SAC TUMOR OF THE ANTERIOR MEDIASTINUM - CASE-REPORT WITH LIGHT-MICROSCOPIC AND ELECTRON-MICROSCOPIC EXAMINATION AND IMMUNOHISTOCHEMICAL STUDY OF ALPHA-FETOPROTEIN

A case of yolk sac tumor of the anterior mediastinum was studied by light and electron microscopy and found to have characteristic patterns which were similar to a neoplasm of gonadal origin. These findings, in addition to the immunohistochemical identification of alpha-fetoprotein in the tumor, indicated that the neoplasm was germ cell in origin. A brief review of previously reported cases is included. Prognosis of the patients with yolk sac tumor of the anterior mediastinum was generally dismal; however, those patients with tumors incidentally found but completely excised survived without evidence of recurrence.