UK practice on incidentally detected non-functioning pituitary microadenomas: analysis of two national surveys during a 12-year interval

Abstract

Purpose: The optimal management approach for presumed non-functioning pituitary microadenomas (microNFPAs) remains unclear. Our aim was to capture current UK practice and identify changes with time. Methods: Two online surveys investigating clinicians' approaches were performed in 2009-2010 and 2021-2022 (advertised through Society for Endocrinology UK). Results: 150 and 214 clinicians participated in the 2021 and 2009 survey, respectively (response rates 31.2% and 35.4%, respectively). At baseline, 2021 survey respondents were more likely to measure IGF-1 (96.0% vs 74.1%, p < 0.001) and morning cortisol (87.9% vs 62.6%, p < 0.001), and less likely GH (26.2% vs 42.6% p = 0.002), 24 h urine free cortisol (3.4% vs 23.2%, p < 0.0001) or dynamically assess adrenal reserve (11.4% vs 30.4%, p < 0.001). 47.2% of clinicians in 2021 would reassess pituitary function annually until discharge (in absence of tumour growth/symptoms). The 2021 survey respondents were more likely to stop imaging at or before 3 years (81.7% vs 44.3%, p < 0.001) and at or before 5 years (86.6.% vs 72.9%, p = 0.002), whilst 2009 survey respondents were more likely to continue imaging beyond 5 years (24% vs 7%, p < 0.001). Responses on imaging frequency/intervals showed notable variability in both surveys. Conclusions: Diagnostic and management approaches for microNFPAs have evolved in the UK. Biochemical investigations are performed in accord with consensus guidelines, though many clinicians perform annual biochemical surveillance without tumour growth/symptoms. A small number of clinicians request imaging beyond 5 years, but the frequency of imaging intervals until discharge remains variable. Robust evidence on the long-term natural history of microNFPAs is necessary to unify clinician approach.