Home / 3D anatomy models / 3D anatomical models of the brain / Pituitary Adenoma

This specimen is from an old case and the investigations used would now be considered antiquated. Modern investigation would include an initial brain CT followed by an MRI of the brain to further visualise the pituitary lesion prior to any surgical intervention. Pituitary adenomas are the most common pituitary tumour and are most commonly found in adults with peak incidence between 35-60 years. Primary carcinoma of the pituitary is very rare, and the pituitary is an uncommon site for metastases. Clinical manifestations of pituitary adenomas are related to local mass effect and tumour function. Local effects include increasing intracranial pressure (headache, nausea and vomiting), sellar expansion, bony erosion and compression of decussating nerve fibres in the optic chiasma, causing bitemporal hemianopia. Pituitary adenomas can be functioning (i.e. associated with hormone excess) or non-functioning (i.e. without clinical symptoms of hormone excess). About 75% of adenomas are functional: usually secreting prolactin, growth hormone or ACTH. Secretion of TSH, LH and FSH from pituitary adenomas is very rare. Some adenomas can secrete two hormones: growth hormone and prolactin being the most common combination. Non-functional pituitary adenomas come to clinical attention later than those associated with endocrine abnormalities, and they may lead to hypopituitarism due to compression atrophy of the surrounding normal gland.