Pituitary tumors Classification and Immunohistochemistry

Pituitary tumors Classification and Immunohistochemistry

M. Tohidi, MD, APCP

Research Institute for Endocrine Sciences

History:

Over the years, several classification schemes have evolved.
Simple tinctorial-based classification was accepted as dogma & dominated pituitary pathology for several decades.
A classification based on tinctorial characteristics of tumor cell cytoplasm fails to provide information regarding cytogenesis, hormone content, cellular composition, endocrine activity & biologic behavior.

General classification of pituitary Tumors:

Benign adenoma
Invasive adenoma
Carcinoma
Oncocytic tumors
Metastatic tumors (breast, lung & GI)
Others: craniopharyngiomas, meningiomas, germ cell tumors; rare granular cell tumors, pituicytomas, and gangliogliomas; and the even rarer gangliocytomas, lymphomas, astrocytomas, and ependymomas

General classification of pituitary Tumors:

Pituitary adenomas are the most common lesions in the sella region;

they represent approximately 10–15% of intracranial neoplasms in most neurosurgery series.
depending on the sections examined they are noted in

3–24% of unselected autopsies.

Classification of pituitary adenomas according to different parameters:

Pituitary adenomas can be classified according to: