Epidemiology, clinical presentation and diagnosis of non-functioning pituitary adenomas.

PURPOSE: Non-functioning pituitary adenomas (NFPAs) are benign pituitary neoplasms that do not cause a hormonal hypersecretory syndrome. An improved understanding of their epidemiology, clinical presentation and diagnosis is needed.

METHOD: A literature review was performed using Pubmed to identify research reports and clinical case series on NFPAs.

RESULTS: They account for 14-54% of pituitary adenomas and have a prevalence of 7-41.3/100,000 population. Their standardized incidence rate is 0.65-2.34/100,000 and the peak occurence is from the fourth to the eighth decade. The clinical spectrum of NFPAs varies from being completely asymptomatic to causing significant hypothalamic/pituitary dysfunction and visual field compromise due to their large size. Most patients present with symptoms of mass effect, such as headaches, visual field defects, ophthalmoplegias, and hypopituitarism but also hyperprolactinaemia due to pituitary stalk deviation and less frequently pituitary apoplexy. Non-functioning pituitary incidentalomas are found on brain imaging performed for an unrelated reason. Diagnostic approach includes magnetic resonance imaging of the sellar region, laboratory evaluations, screening for hormone hypersecretion and for hypopituitarism, and a visual field examination if the lesion abuts the optic nerves or chiasm.

CONCLUSION: This article reviews the epidemiology, clinical behaviour and diagnostic approach of non-functioning pituitary adenomas.