NCT07108244

Use of [18F]FET PET-MRI to Improve Detection of Pituitary Adenomas in Cushing's Disease

Use of [18F]FET PET-MRI to Improve Detection of Pituitary Adenomas in Cushing's Disease - a Prospective Diagnostic Study

• Status: Enrolling By Invitation
• Phase: N/A
• Study type: Interventional
• Enrollment: 43 (estimated)
• Sponsor: University Hospital, Basel, Switzerland · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

In ACTH-dependent hypercortisolism it is important to distinguish between Cushing's disease (CD), with ACTH production by a pituitary neuroendocrine tumour (PitNET) and Cushing's syndrome (CS), with ectopic ACTH production. Bilateral inferior petrosal sinus sampling (IPSS) is the gold standard for this distinction, with a diagnostic accuracy of 98%. However, IPSS is an invasive procedure and an indi-rect diagnostic method, rarely providing reliable data on the exact location of the PitNET. This has a major impact on the therapeutic approach, short and long-term remission rates, and other outcomes. Hybrid Positron-emission tomography-Magnetic Resonance Imaging (PET-MRI) using O-(2-\[18F\]-fluo-roethyl)-L-tyrosine (\[18F\]FET) is promising in this respect. Recent data published by our research group demonstrate a a sensitivity of 100% a high accuracy in in the precise localization of ACTH-secreting PitNETs. We hypothesize that \[18F\]FET PET-MRI could become the new non-invasive diagnostic stand-ard, but data regarding a direct comparison between the diagnostic impact of \[18F\]FET PET-MRI versus IPSS in the differentiation between CD and ectopic CS are lacking. In addition, there are currently no other reliable biomarkers to distinguish the two disorders. The investigators hypothesize that the ACTH-dependent biomarker copeptin could be a valuable addition in this regard. The aim of this prospective diagnostic study is to compare the diagnostic accuracy of \[18F\]FET-PET-MRI and IPSS in differentiating CD from ectopic CS in patients with ACTH-dependent hypercortisolism.

Conditions

• Cushing Disease

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	[18F]FET PET-MRI	All participants will undergo both \[18F\]fluoroethyltyrosine positron emission tomography-magnetic resonance imaging (\[18F\]FET-PET-MRI) and inferior petrosal sinus sampling (IPSS) as part of the diagnostic work-up for ACTH-dependent hypercortisolism. The purpose is to compare the diagnostic accuracy of these two modalities in distinguishing Cushing's disease from ectopic ACTH secretion. The results from both diagnostic tests will be communicated to the treating medical team and the participant to guide further clinical management.

Timeline

• Start date: 2025-10-22
• Primary completion: 2029-07-30
• Completion: 2029-07-30
• First posted: 2025-08-06
• Last updated: 2025-12-19

Locations

2 sites across 2 countries: Netherlands, Switzerland