Pituitary adenoma

• Pituitary adenoma:

  • Occur in the pituitary gland - responsible for 15% of primary brain tumours
  • Can be functional and secrete hormones
  • Larger tumours (>1cm) are usually non-functional and cause symptoms by mass effect
  • Most are benign
  • Pituitary macroadenomas are the most common cause of hypopituitarism
• Functional pituitary adenomas can cause a variety of clinical presentations including:

  • Cushingoid symptoms
  • Acromegaly
  • Diabetes insipidus
  • Hyperpituitarism
  • Amenorrhea/galactorrhoea/impotence
• Clinical features related to the mass effect of the tumour may include:

  • Bitemporal hemianopia: due to compression of the optic chiasm
  • Hydrocephalus
  • Diplopia
• Relevant investigations include:

  • Endocrine laboratory tests
  • MRI with gadolinium contrast +/- CT
• Management of pituitary tumours may include:

  • Dopamine agonists to treat prolactinomas
  • Surgery
  • Radiation therapy
• Pituitary apoplexy:

  • Serious complication - haemorrhage causes rapid increase in the size of the lesion and surrounding vasogenic oedema
  • Due to the mass effect, surrounding necrosis occurs
  • Results in sudden onset severe headache, visual loss, hydrocephalus