Evaluation of Positron Emission Tomography (PET) With [18F]FET for the Detection of ACTH-Secreting Corticotroph Pituitary Neuroendocrine Tumors.

NCT07463625 | Recruiting

• 1 other identifier: 25-5027
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Cushing's disease results from adrenocorticotropic hormone (ACTH) secretion by corticotroph pituitary neuroendocrine tumors (PitNETs). Magnetic resonance imaging (MRI) is the reference modality for etiological diagnosis but may to visualize small corticotroph microadenomas in up to 30% of the cases, and false positives may occur. The study hypothesis is that positron emission tomography (PET) using \[18F\]fluoroethyl-L-tyrosine (\[18F\]FET) improves localization of ACTH-secreting corticotroph microadenomas compared with MRI and could inform surgical planning and reduce reliance on invasive inferior petrosal sinus sampling. This observational cohort (retrospective and prospective data) will assess the diagnostic performance of \[18F\]FET PET for tumor localization using postoperative histopathology as the gold standard. Secondary aims include:

1. 1.assessing cases in which PET modifies localization relative to MRI and is correct by gold standard;
2. 2.inter-reader agreement between two nuclear medicine physicians;
3. 3.correlations between PET signal and biochemical markers of hypercortisolism
4. 4.uni- and multivariable analyses of clinical and imaging parameters influencing PET results;
5. 5.association between PET findings and subsequent biological remission.

Conditions

Cushing Disease; ACTH-producing Pituitary Tumour

Keywords

PET; Cushing disease; [18F]FET; PitNET; Corticotroph adenoma; ACTH; Pituitary; MRI; Amino-acid

Outcome Measures

Primary Outcomes (1)

• [18F]FET PET Performance for Localizing Corticotroph Pituitary Adenomas

  Proportion (%) of correct localization of the adenoma by \[18F\]FET PET, using postoperative histopathological examination of the surgical specimen as the reference standard.

  3 months

Secondary Outcomes (5)

• Effect of PET on Tumor Localization Versus MRI

  3 months

• Inter-Reader Agreement of [18F]FET PET Interpretation

  1 month

• Correlation Between PET SUV and Hypercortisolism Biomarkers

  3 months

• Determinants of PET Performance (Clinical/Biological/Imaging)

  3 months

• Prognostic Value of PET Findings for Biological Remission

  3 months

Study Arms (1)

Adults with Cushing's disease evaluated for pituitary surgery

Adults (≥18 years) with biochemically confirmed Cushing's disease with negative or doubtlful or microadenoma on pituitary MRI and are discussed for surgical management; who benefited from a\[18F\]FET PET in their clinical work-up.

Other: Data-only evaluation of [18F]FET PET, pituitary MRI, and biomarkers

Interventions

Data-only evaluation of [18F]FET PET, pituitary MRI, and biomarkers OTHER

No study-specific procedures. The study evaluates existing \[18F\]FET PET imaging pituitary MRI, and routine biochemical markers collected as part of standard care.

Adults with Cushing's disease evaluated for pituitary surgery

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adults treated at a tertiary academic hospital with biochemically confirmed Cushing's disease, evaluated by pituitary MRI and \[18F\]FET PET as part of diagnostic work-up, and discussed for surgery.

You may qualify if:

• Adults (≥18 years).
• Biochemical diagnosis of Cushing's disease as part of initial management.
• Pituitary MRI performed; if visible, microadenoma \<10 mm in diameter.
• Indication for discussion in multidisciplinary tumor board for surgical management.

You may not qualify if:

• Minor (age \<18 years).
• Macroadenoma of the pituitary.
• ACTH-dependent hypercortisolism secondary to ectopic secretion.

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (1)

Hôpital Louis Pradel - Service de Médecine Nucléaire

Bron, 69500, France

RECRUITING

MeSH Terms

Conditions

Pituitary ACTH Hypersecretion; ACTH-Secreting Pituitary Adenoma; Pituitary Diseases

Interventions

Biomarkers

Condition Hierarchy (Ancestors)

Hyperpituitarism; Hypothalamic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Endocrine System Diseases; Adenoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Neoplasms; Pituitary Neoplasms; Endocrine Gland Neoplasms; Neoplasms by Site

Intervention Hierarchy (Ancestors)

Biological Factors

Central Study Contacts

Anthime FLAUS, MD

CONTACT

+33 4 72 35 69 99; anthime.flaus@chu-lyon.fr

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 2, 2026
• First Posted: March 11, 2026
• Study Start: November 23, 2023
• Primary Completion (Estimated): November 23, 2027
• Study Completion (Estimated): November 23, 2028
• Last Updated: March 11, 2026

Record last verified: 2026-03

Locations

FR (1)