New Imaging Techniques in the Evaluation of Patients With Ectopic Cushing Syndrome
Cushing Syndrome is an endocrine disorder causing an over production of the hormone cortisol. Cortisol is produced in the adrenal gland as a response to the production of ACTH in the pituitary gland.
Between 10% and 20% of patients with hypercortisolism (Cushing Syndrome) have ectopic production of the hormone ACTH. Meaning, the hormone is not being released from the normal site, the pituitary gland. In many cases the ectopic ACTH is being produced by a tumor of the lung, thymus, or pancreas. However, in approximately 50% of these patients the source of the ACTH cannot be found even with the use of extensive imaging studies such as CT scans, MRIs, and nuclear scans (111-indium pentetreotide). The ability of these tests to locate the source of the hormone production is dependent on the changes of anatomy and / or the dose and adequate uptake of the radioactive agent. The inability to detect the source of ectopic ACTH production often results in unnecessary pituitary surgery or irradiation.
Unlike the previously described tests, positron emission tomography (PET scan) has the ability to detect pathologic tissue based on physiologic and biochemical processes within the abnormal tissue.
This study will test whether [18-F]-fluorodeoxyglucose (FDG) or use of a higher dose of [111In-DTPA-D-Phe]-pentetreotide can be used to successfully localize the source of ectopic ACTH production.< TAB>
Drug: (18F)-L-3,4-dihydroxyophenylalanine (18F-DOPA)
|Study Design:||Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Diagnostic
|Official Title:||New Imaging Modalities in the Evaluation of Patients With Ectopic Cushing's Syndrome|
- Sensitivity, specificity and diagnostic accuracy of imaging modalities for the detection of ACTH-secreting non-pituitary tumor
|Study Start Date:||February 1999|
|Estimated Study Completion Date:||December 2019|
|Estimated Primary Completion Date:||December 2019 (Final data collection date for primary outcome measure)|
Between 10 percent and 20 percent of patients with hypercortisolism (Cushing syndrome) have ectopic production of adrenocorticotropin hormone (ACTH) that causes cortisol excess. In approximately 50 percent of these patients, the source of ACTH cannot be found despite very detailed and extensive examination including imaging studies such as computed tomography scanning, magnetic resonance imaging, and octreotide scan using the conventional low dose of indium-111 pentetreotide ([(111)In-DTPA-D-Phe]-pentetreotide). The sensitivity and specificity of these imaging studies depends on anatomic alterations and/or the dose and adequate uptake of radiopharmaceutical. In contrast, positron emission tomography (PET) has the ability to detect pathologic tissue based on physiologic and biochemical processes within the abnormal tissue. This protocol tests whether [18F]-L-3,4-dihydroxyphenylalanine (18F-DOPA) or use of a higher dose of [111In-DTPA-D-Phe]-pentetreotide can be used to localize successfully the source of ectopic ACTH production. In addition the study examines whether administration of the glucocorticoid antagonist mifepristone can improved the sensitivity of the standard dose [111 In-DTPA-D-Phe] pentetreotide. Patients participating in this arm of the study will have a second standard dose scan rather than a higher dose scan.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00001849
|Contact: Mai Lloyd||(301) firstname.lastname@example.org|
|Contact: Lynnette K Nieman, M.D.||(301) email@example.com|
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike||Recruiting|
|Bethesda, Maryland, United States, 20892|
|Contact: For more information at the NIH Clinical Center contact Patient Recruitment and Public Liaison Office (PRPL) 800-411-1222 ext TTY8664111010 firstname.lastname@example.org|
|Principal Investigator:||Lynnette K Nieman, M.D.||Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)|