ACTH-producing Pituitary Tumour, Cushing Disease
Conditions
Keywords
PET, Cushing disease, [18F]FET, PitNET, Corticotroph adenoma, ACTH, Pituitary, MRI, Amino-acid
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. assessing cases in which PET modifies localization relative to MRI and is correct by gold standard; 2. inter-reader agreement between two nuclear medicine physicians; 3. correlations between PET signal and biochemical markers of hypercortisolism 4. uni- and multivariable analyses of clinical and imaging parameters influencing PET results; 5. association between PET findings and subsequent biological remission.
Interventions
OTHERData-only evaluation of [18F]FET PET, pituitary MRI, and biomarkers
No study-specific procedures. The study evaluates existing \[18F\]FET PET imaging pituitary MRI, and routine biochemical markers collected as part of standard care.
Sponsors
Hospices Civils de Lyon
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* 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.
Exclusion criteria
* Minor (age \<18 years). * Macroadenoma of the pituitary. * ACTH-dependent hypercortisolism secondary to ectopic secretion.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| [18F]FET PET Performance for Localizing Corticotroph Pituitary Adenomas | 3 months | Proportion (%) of correct localization of the adenoma by \[18F\]FET PET, using postoperative histopathological examination of the surgical specimen as the reference standard. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Effect of PET on Tumor Localization Versus MRI | 3 months | Among cases in which the PET-suggested localization differs from MRI, the proportion (%) in which PET correctly localizes the adenoma (per the primary endpoint definition). |
| Inter-Reader Agreement of [18F]FET PET Interpretation | 1 month | Proportion (%) agreement between the two nuclear medicine physicians' PET interpretations (inter-reader agreement). |
| Correlation Between PET SUV and Hypercortisolism Biomarkers | 3 months | Correlation between \[18F\]FET PET and biochemical markers |
| Determinants of PET Performance (Clinical/Biological/Imaging) | 3 months | Univariable and multivariable analyses of variables that may influence PET results. |
| Prognostic Value of PET Findings for Biological Remission | 3 months | Correlation between PET results and the patient's biological status at follow-up (biological remission-e.g., corticotroph inertia or normalization of urinary free cortisol (UFC)-versus active hypercortisolism). |
Countries
France
Contacts
CONTACTAnthime FLAUS, MD
Outcome results
None listed