Pituitary Innovation and Teaching

Pituitary tumours: Types of tumours and symptoms

What is a pituitary tumour?

A pituitary tumour (adenoma) occurs when the cells in the pituitary gland grow out of control and form a mass (see Figures 1-4 below).

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Most pituitary tumours are not cancerous. The risk of the tumour spreading to other parts of the brain or your body is very low.

There are two types of pituitary tumours. One type is called a ‘functioning adenoma’, and the other is called a ‘non-functioning adenoma’.

Functioning adenomas may cause the pituitary gland to make too much of one of the pituitary hormones. If the tumour makes too much prolactin, growth hormone or ACTH, the patient will have changes in their body, depending on which hormone it is. Non-functioning adenomas do not make hormones. Both types of tumours can cause the pituitary gland to stop one or more of its normal hormone functions.

Both types of tumours can press on the nerves that help a person to see and so can cause problems with vision.

How common is it?

One out of every three people can have a pituitary tumour and never know it. This is because the tumour rarely grows large enough to cause any symptoms. Pituitary tumours usually grow very slowly. It may take years before people start to notice something is wrong.

How do I know if I have a pituitary tumour?

There are tests to see if you have a pituitary tumour. The tests measure hormone levels in your blood and urine. If your hormone levels are very high, this could mean that you have a pituitary tumour. Other tests are brain scans called MRIs or CT scans and vision tests to check eyesight.

Types of tumours and symptoms

Illustation for types of tumoursThere are two types of pituitary tumours. Both types can press on the nerves of your eyes and cause problems.

Types of functioning tumours (make too much pituitary hormone):

  1. Prolactin-producing tumours (Prolactinomas)
  2. Growth hormone-producing tumours (Acromegaly)
  3. ACTH-producing tumours (Cushing’s disease)

Non-functioning tumours:

  • Non-functional pituitary adenoma
  • Craniopharyngioma

The following are other common pituitary diseases:

  1. Rathke’s cleft cyst
  2. Pituitary apoplexy
  3. Craniopharyngioma

The symptoms that are caused by a pituitary tumour depend on:

  • the size of the tumour
  • how it affects the making of hormones in your body
  • how the tumour affects your brain and eyes.

Types of functioning tumours (Adenomas)

Prolactin-producing tumours (Prolactinomas)

Growth hormone-producing tumours (Acromegaly)

ACTH-producing tumours (Cushing’s disease)

Non-functioning tumours (adenomas)

Other common pituitary diseases


Page last updated: November 22, 2016