[Characteristic ultrastructural features of parathyroid gland cancer. A report on 9 cases (author's transl)].

Authors have studied 9 parathyroid carcinomas under electron microscope (3% of their parathyroid lesions). Two types of the ultrastructural features were significant: 1) architectural: basal membrane abnormalities, sparse desmosomes, absence of nerve fiber; 2) cytological: nuclei atypism and abnormal mitochondria in tumors cells resembling dark chief cells. Also noticed were signs of cell hyperactivity and/or trouble in parathormon production or regulation.