What is a pituitary adenoma or a neuroendocrine tumor of the pituitary gland?

Pituitary adenomas are benign, slow-growing tumours that originate from the anterior pituitary cells.


How common are they?

The incidence of pituitary adenomas is 4.0 per 100,000 people, while the development of neuroimaging in recent years has allowed faster detection and therefore more successful treatment.


What is micro- and macro-adenoma?

Depending on their size, they are divided into micro (<1 cm) and macro (>1 cm) adenomas.


What symptoms are caused by pituitary adenomas?

The symptoms caused by pituitary adenomas depend on their size and whether they hyper- secrete a hormone:


What are functioning (secreting) and non-functioning (non-secreting) pituitary adenomas?

Depending on whether they produce excess hormones or not, they are divided into functioning or non-functioning adenomas.

Pituitary adenomas are divided into:


How are pituitary adenomas diagnosed?

The diagnosis of pituitary adenomas requires:

  • physical examination,
  • history,
  • neuro-imaging (e.g. MRI)
  • but also hormonal testing to determine which hormone is over- or under-secreted,
  • while specialised endocrine tests are often required

How are pituitary adenomas treated?

The treatment of pituitary adenomas depends on whether they are functioning, their size, how fast they grow, their mass effect, age and comorbidities and the patient’s preference. Their treatment as well as their diagnosis is determined by a multidisciplinary team, which includes endocrinologist, neurosurgeon, radiologist, oncologist, pathologist and requires a specialized centre. It usually includes:

  • endoscopic transphenoidal excision and/or craniotomy
  • radiotherapy
  • medical treatment
  • hormonal replacement
  • wait and watch

Some adenomas, such as prolactinomas, respond extremely well to medication. In larger adenomas, a combination of surgical excision, pharmacotherapy and radiation is often required. Hormone replacement therapy of the hormones that become deficient due to destruction of the hormone-producing cells of the pituitary gland, either by tumour pressure or as a consequence of the treatment is a vital part of treatment.