Pituitary Neoplasms

**Definition:** Neoplasms which arise from or metastasize to the PITUITARY GLAND. The majority of pituitary neoplasms are adenomas, which are divided into non-secreting and secreting forms. Hormone producing forms are further classified by the type of hormone they secrete. Pituitary adenomas may also be characterized by their staining properties (see ADENOMA, BASOPHIL; ADENOMA, ACIDOPHIL; and ADENOMA, CHROMOPHOBE). Pituitary tumors may compress adjacent structures, including the HYPOTHALAMUS, several CRANIAL NERVES, and the OPTIC CHIASM. Chiasmal compression may result in bitemporal HEMIANOPSIA.

**Tree numbers:** - C04.588.322.609 - C04.588.614.250.195.885.500.600 - C10.228.140.211.885.500.600 - C10.228.140.617.477.600 - C10.228.140.617.738.675 - C10.551.240.250.700.500.500 - C19.344.609 - C19.700.734

**Synonyms:** - Pituitary Tumors