New Imaging Techniques in the Evaluation of Patients With Ectopic Cushing Syndrome

Summary

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 corticotropin (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 computed tomography (CT) scans, magnetic resonance imaging (MRI), 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 fluorine-18-fluorodeoxyglucose (FDG), fluorine-18-dihydroxyphenylalanine (F-DOPA) or use of a higher dose of 111-indium pentetreotide can be used to successfully localize the source of ectopic ACTH production.

Conditions

• Cushing Syndrome
• Endocrine Disease

Interventions

DRUG

Pentetreotide

Binds primarily to the somatostatin receptors subtypes (sst) 2 and 5. A high dose (18mCi) was used if the conventional dose (6mCi) was negative and scheduling was available. High doses limited to 3 over the course of the study.

DRUG

18F-DOPA

18F-DOPA is a radiolabeled amino acid used as a radiotracer in positron emission tomography (PET). Limited to 3 doses over the course of the study.

DEVICE

CT scan

CT scan of chest, abdomen, neck and /or pelvis

DEVICE

MRI

MRI scan of head/pituitary, chest, abdomen, neck and /or pelvis

DRUG

18-FDG

FDG PET scan of body

Sponsors & Collaborators

• Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

  lead NIH

Principal Investigators

• Lynnette K Nieman, M.D. · National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Study Design

Allocation

NA

Purpose

DIAGNOSTIC

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

90 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

1999-05-20

Primary Completion

2019-04-26

Completion

2019-04-26

FDA Drug

Yes

Countries

• United States

Study Locations