Management of non-functioning pituitary adenomas
Non-functioning pituitary adenomas (NFAs) are benign pituitary neoplasms arising from the adenohypophyseal cells. They are not associated with clinical evidence of hormonal hypersecretion and have a prevalence of 22 cases per 100,000 people. At presentation, the majority is macroadenomas and their clinical manifestations are the result of pressure effects to surrounding structures.
Management options include observation, surgical removal combined or not with external irradiation, radiotherapy alone or medical treatment.
Studies assessing the natural history of presumed NFAs, have shown probability of enlargement 19% for microadenomas and 44% for macroadenomas at 48 months. Surgery remains the treatment of choice in patients with macroadenomas and achieves improvement of vision in around 80% of the cases. Hypopituitarism (partial or complete) is present in a significant number of patients post-operatively (3083%) and its rate increases following radiotherapy. Regrowth rates in subjects treated solely by surgery range between 646% (the risk is higher if there is large tumour remnant) and in those managed by surgery and adjuvant radiotherapy between 036%. Up to 20% of the relapses have been detected 10 years post-operatively necessitating long-term surveillance. Reliable markers of tumour relapse at a pathological and/or molecular level are lacking.
The management of patients presenting with pituitary apoplexy (conservative or surgical) is dictated by the presence of pressure effects and careful monitoring for recurrence is required post-operatively (11.1% at a mean follow up of 6.6 years).
The value of medical treatments (dopamine agonists, somatostatin analogues) remains to be assessed.
Recent data from the Oxford series suggest that the quality of life of patients with NFAs following treatment (surgery combined or not with radiotherapy) is not compromised to a significant extent.
Finally, the impact of NFAs on the long-term mortality is not as yet, clear.
Declaration of interest: The author declares that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.