Endocrine Abstracts

Background: Secretory pancreatic neuroendocrine tumours (PanNET) are common in MEN1. The MEN1 Clinical Practice guideline (Thakker, 2012) recommends annual assessment of fasting gut hormones (FGH) with annual pancreatic imaging for routine NET surveillance in MEN1.

Study aim: To determine whether FGH (gastrin, glucagon, somatostatin, pancreatic polypeptide, VIP, insulin, chromogranin-A) in a cohort of asymptomatic individuals with a genetic diagnosis of MEN1, over a 5 year period, changed patient management.

Study design: Single centre retrospective case series. Inclusion criteria: individuals with MEN1 undergoing routine surveillance, including those with non-functioning PanNET and those with previously resected PanNET. Exclusion criteria: individuals with symptoms suggestive of a functioning PanNET (hypoglycaemia, profuse diarrhoea, significant acid-reflux) and those on somatostatin analogue therapy (SSA).

Study participants: 43/54 people with MEN1 met the inclusion criteria (26M, 17F, age range 22-84 year). 11 were excluded (3 due to symptoms; 8 due to SSA therapy). 169 FGH panels were analysed.

Results: 94/169 (56%) FGH panels contained 1 or more abnormal result. Chromogranin A was most frequently abnormal (62/169 panels; 37%), followed by glucagon (28%) and gastrin (20%). Abnormal VIP and somatostatin were uncommon (1% and 0.6%, respectively). 22/169 (13%) panels contained a result more than 3 times the upper limit of normal (ULN); 9 (5%) had a result more than 10 times ULN. Over 5 years, 142 pancreatic MRI scans were performed where paired FGH were available. 89/142 MRIs were reported as normal. 53/89 (60%) were paired with a completely normal FGH panel. Taken in isolation, the FGH results did not change patient management across the series.

Conclusions: FGHs are frequently abnormal in asymptomatic people with MEN1 undergoing routine surveillance, with doubtful clinical significance. Taken in isolation, these do not alter management however, the FGH trends over time can be useful when interpreted in the context of serial radiological findings.