Pituitary Carcinoma: An Ultrastructural Study of Eleven Cases
- 1 January 2001
- journal article
- research article
- Published by Taylor & Francis Ltd in Ultrastructural Pathology
- Vol. 25 (3), 227-242
- https://doi.org/10.1080/019131201300343865
Abstract
Pituitary carcinomas are very rare. Defined as adenohypophysial tumors that undergo craniospinal and/or systemic metastasis, most are PRL- or ACTH-producing. Their ultrastructural features, particularly relative to benign adenomas of similar functional type, have not been sufficiently explored. Eleven cases of immunohistochemically characterized pituitary carcinoma with documented cerebrospinal and/or systemic metastases were collected from various institutions and studied by transmission electron microscopy. The tumors were surgically removed from 7 women and 4 men ranging in age between 28 and 74 years (mean, 50 years). All were endocrinologically functioning. Six tumors secreted PRL; three were ACTH-producing; one each was GH/PRL- and TSH-producing. The patients with the ACTH-producing tumors had all presented with Cushing's disease and two of them had undergone adrenalectomy (Nelson syndrome). In most cases significant cellular atypia and mitotic activity were observed. In terms of morphologic features of functional differentiation, electron microscopy revealed that in 9 cases the tumor cells maintained at least some ultrastructural markers of their basic phenotype. A unique feature in 2 ACTH carcinomas was the variable admixture of smooth endoplasmic reticulum with intermediate (cytokeratin) filaments. In 2 cases, both PRL-producing carcinomas, the cell type comprising the tumor could not be identified on an ultrastructural basis alone. Ultrastructural investigation of pituitary carcinomas confirms their endocrine nature and, in most but not all cases, reveals their functional differentiation. Despite the diagnostic utility of electron microscopy in the assessment of theserare tumors, the distinction of pituitary carcinoma from pituitary adenoma cannot be firmly made on ultrastructural grounds alone.Keywords
This publication has 13 references indexed in Scilit:
- Intracranial metastases from pituitary adenomaBritish Journal of Neurosurgery, 1995
- Pituitary CarcinomaJournal of Neurological Surgery Part B: Skull Base, 1994
- Malignant Prolactinoma With Extracranial MetastasesObstetrical & Gynecological Survey, 1993
- Malignant Prolactinoma with Multiple Intracranial Metastases Studied with Positron Emission TomographyNeurosurgery, 1988
- Subarachnoid dissemination of a pituitary adenomaSurgical Neurology, 1987
- Mammosomatotroph adenoma of the pituitary associated with gigantism and hyperprolactinemia. A morphological study including immunoelectron microscopyActa Neuropathologica, 1986
- MULTIPLE INTRACRANIAL METASTASES FROM A PROLACTIN SECRETING PITUITARY TUMOURClinical Endocrinology, 1985
- Primary Pituitary Carcinoma: A Clinical Pathological StudyNeurosurgery, 1985
- Pituitary Adenomas Producing Growth Hormone, Prolactin, and One or More Glycoprotein Hormones: A Histologic, Immunohistochemical, and Ultrastructural Study of Four Surgically Removed TumorsUltrastructural Pathology, 1983
- Carcinoma of the pituitary glandThe Journal of Pathology, 1973