Walsh & Hoyt: General Considerations

The characteristic pituitary tumor is the adenoma. Uncommon in children, its incidence increases with age and may approach 30% in an older population. Pituitary adenomas constitute 612% of all symptomatic intracranial tumors. Most are sporadic, but pituitary adenomas are a component of multiple endocrine neoplasia type 1, a familial endocrine cancer syndrome characterized by primary hyperparathyroidism, endocrine enteropancreatic tumors, and adrenocortical and thymic/bronchial neuroendocrine tumors. As a pituitary adenoma grows and extends beyond the sella turcica, it may then impinge upon the visual pathways, especially the chiasm, and the ocular motor cranial nerves in the cavernous sinus.