A Phase 2 interventional study of DOTATATE PET-CT and F-DOPA PET CT in ACTH and Cushing's Syndrome, sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Recruiting at 1 site in United States. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-10-02.
Sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) · Phase 2, Interventional, and Diagnostic
Between 10% and 15% of patients with endogenous hypercortisolism (Cushing syndrome) have ectopic (non-pituitary) production of adrenocorticotropin hormone (ACTH) that causes cortisol excess. In approximately 50% of these patients, the tumoral source of ACTH cannot be found initially despite very detailed and extensive imaging, including studies such as computed tomography, magnetic resonance imaging, and octreotide scan (Octreoscan) using the standard dose of indium- 111 pentetreotide ([111In-DTPA-D-Phe]-pentetreotide). The sensitivity and specificity of structurally based imaging studies depends on anatomic alterations and the size of the tumor. In contrast, positron emission tomography (PET) and somatostatin ligand imaging detect pathologic tissue based on physiologic and biochemical processes within the abnormal tissue. This protocol tests the ability of [18F]-L-3,4-dihydroxyphenylalanine (18F-DOPA) PET, and the somatostatin imaging analogue, 68Ga-DOTATATE-PET, to localize the source of ectopic ACTH production.
Study Description:
Between 10% and 15% of patients with endogenous hypercortisolism (Cushing syndrome) have ectopic (non-pituitary) production of adrenocorticotropin hormone (ACTH) that causes cortisol excess. In approximately 50% of these patients, the tumoral source of ACTH cannot be found initially despite very detailed and extensive imaging, including studies such as computed tomography, magnetic resonance imaging, and octreotide scan (Octreoscan) using the standard dose of indium- 111 pentetreotide ([111In-DTPA-D-Phe]-pentetreotide). The sensitivity and specificity of structurally based imaging studies depends on anatomic alterations and the size of the tumor. In contrast, positron emission tomography (PET) and somatostatin ligand imaging detect pathologic tissue based on physiologic and biochemical processes within the abnormal tissue.
This protocol tests the ability of [18F]-L-3,4-dihydroxyphenylalanine (18F-DOPA) PET, and the somatostatin imaging analogue, 68Ga-DOTATATE-PET, to localize the source of ectopic ACTH production.
Objectives:
Primary Objectives:
Secondary Objective:
-To evaluate a potential correlation between 18F-DOPA or 68Ga-DOTATATE uptake and the type of tumor, its size, SSTR expression or proliferative activity.
Exploratory Objectives:
Endpoints:
Primary Endpoint:
-Imaging results and pathology of resected tumors
Secondary Endpoints:
-18F-DOPA or 68Ga-DOTATATE imaging results, tumor pathology, tumor size, proliferative index and SSTR expression.
Exploratory Endpoints:
123 studies on the registry are indexed under Cushing Syndrome; 37 are open to participants now.
This study's planned enrollment of 80 is above the median of 50 across 59 interventional studies indexed under Cushing Syndrome.
Browse Cushing Syndrome studies →National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) is the lead sponsor of 529 studies on the registry; 54 are open to participants now.
Of its 79 completed or terminated interventional studies of FDA-regulated products, 50 (63%) have results posted.
Counted across the registry records on this site, refreshed daily.
To be eligible to participate in this study, an individual must meet all of the following criteria:
EXCLUSION CRITERIA:
An individual who meets any of the following criteria will be excluded from participation in this study:
All subjects will be imaged
Radiation: DOTATATE PET-CT · Radiation: F-DOPA PET CT · Radiation: CT scan · Diagnostic Test: Routine MRI scan · Diagnostic Test: Gated MRI scan · Drug: 68Ga-DOTATATE · Drug: 18F-DOPA
68Ga-DOTATATE PET/CT
68Ga-DOTATATE PET/CT
routine CT scan
routine 1.5 or 3T MRI scan
Cardiac gated MRI scan
68Ga-DOTATATE radioligand
18F-DOPA radioligand
To determine which imaging technique (F-DOPA PET/CT, 68Ga-DOTATATE PET/CT, CT, and/or MRI) has the best sensitivity.
Subjects will be imaged every 6-12 months until tumor is found
Time frame: 6-12 months
To determine if there is a combination of imaging tests with optimal diagnostic accuracy.
subjects will be imaged every 6-12 months until tumor is found
Time frame: 6-12 months
To evaluate a potential correlation between 18F-DOPA or 68Ga-DOTATATE uptake and the type of tumor, its size, SSTR expression or proliferative activity.
Time frame: Ongoing
Plan to share: Yes — On request, IPD related to a publication will be made available.
Supporting information: Csr, Analytic code
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)