The pituitary is a small endocrine gland found within a bony structure in the skull called the sella turcica. It is located below the optic chiasm and hypothalamus and is connected with the latter by the hypothalamic-pituitary stalk. There are important structures in the area around the pituitary such as the optic nerves, the cavernous sinus, carotid arteries and some cranial nerves.
The pituitary gland is divided into two parts:
- Anterior (adenohypophysis).
- Posterior (neurohypophysis).
The pituitary gland produces certain hormones (ACTH, TSH, GH, PRL, LH and FSH) that control the secretion of endocrine glands in the rest of the body. It has a very important role in the regulation of some vital features like:
- Sexual development and behavior.
- Functions related to reproduction, pregnancy and lactation.
- Funciones relacionadas con la reproducción, embarazo y lactancia.
- The metabolism.
- Energy balance of the body.
- Response to stress.
- Regulation of water and ion balance.
A pituitary adenoma is a benign tumor of the anterior part of the pituitary (adenohypophysis). These adenomas can be classified:
- From the functional point of view:
- Non-secreting (do not produce hormones)
- Secreting (produce hormones and cause syndromes of hormonal hyper secretion).
- Classified by size: :
- Microadenomas (less than 1 cm in diameter)
- Macroadenomas (greater than 1 cm in diameter)
The pituitary adenoma must be differentiated from other types of tumors located in the same anatomical region such as meningiomas or craniopharyngiomas.
Pituitary adenomas account for approximately 10% of all primary intracranial tumors with a prevalence of around 70-100 cases per 100,000 persons.