Diagnosis of Pheochromocytoma

Pheochromocytoma Clinical Trial

Official title: Diagnosis, Pathophysiology, and Molecular Biology of Pheochromocytoma and Paraganglioma

Status Recruiting

Clinical Trial Summary

The goal of this study is to develop better methods of diagnosis, localization, and treatment for pheochromocytomas. These tumors, which usually arise from the adrenal glands, are often difficult to detect with current methods. Pheochromocytomas release chemicals called catecholamines, causing high blood pressure. Undetected, the tumors can lead to severe medical consequences, including stroke, heart attack and sudden death, in situations that would normally pose little or no risk, such as surgery, general anesthesia or childbirth.

Patients with pheochromocytoma may be eligible for this study. Candidates will be screened with a medical history and physical examination, electrocardiogram, and blood and urine tests. Study participants will undergo blood, urine, and imaging tests, described below, to detect pheochromocytoma. If a tumor is found, the patient will be offered surgery. If surgery is not feasible (for example, if there are multiple tumors that cannot be removed), evaluations will continue in follow-up visits. If the tumor cannot be found, the patient will be offered medical treatment and efforts to detect the tumor will continue. Main diagnostic and research tests may include the following:

1. Blood tests - mainly measurements of plasma or urine catecholamines and metanephrines as well as methoxytyramine. If necessary the clonidine suppression test can be carried out.

2. Standard imaging tests - Non-investigational imaging tests include computed tomography (CT), magnetic resonance imaging (MRI), sonography, and 123I-MIBG scintigraphy and FDG (positron emission tomography) PET/CT. These scans may be done before and/or after surgical removal of pheochromocytoma.

3. Research PET scanning is done using an injection of radioactive compounds. Patients may undergo 18F-FDOPA, 18F-DA, as well as 68Ga-DOTATATE PET/CT . Each scan takes up to about 2 hours.

4. Genetic testing - A small blood sample is collected for DNA analysis and other analyses.

Clinical Trial Description

Pheochromocytomas (PHEOs) and paragangliomas (PGLs) are rare and clinically important chromaffin cell tumors that typically arise from the adrenal gland or from extra-adrenal paraganglia, respectively. The clinical features and consequences of PHEO/PGL result from the release of catecholamines (norepinephrine and/or epinephrine). An undetected PHEO/PGL poses a hazard to patients undergoing surgery, childbirth, or general anesthesia, due to the potential for excess catecholamine secretion, which can result in significant, often catastrophic outcomes. Diagnosing and localizing a PHEO/PGL can be challenging. Plasma and urinary catecholamines as well as their metabolites and radio-iodinated metaiodobenzylguanidine (MIBG) scanning can yield false-positive/negative results in patients harboring the tumor. Computed tomography (CT) and magnetic resonance imaging (MRI) lack sufficient specificity. The molecular mechanisms by which genotypic changes predispose to the development of PHEO/PGL remain unknown - even in patients with identified pathogenic variants. Moreover, in patients with hereditary predispositions, PHEOs/PGLs differ in terms of their growth, malignant potential, catecholamine phenotype, responses to standard screening tests, various imaging modalities and therefore subsequently, different therapeutic options. This protocol focuses on developmental, molecular, genetic, epigenetic, proteomic, metabolomics, immunologic and other types of studies to investigate the bases for predisposition to develop PHEOs/PGLs and for expression of different neurochemical and other phenotypes and malignant potentials including therapeutic responses. Furthermore, this protocol will also use new imaging approaches, for example [18F]-6F-dopamine ([18F]-6F-DA), and [18F]-L-3,4-dihydroxyphenylalanine ([18F]-FDOPA) positron emission tomography (PET)/CT, as well as dynamic contrast-enhanced MRI. ;

Related Conditions & MeSH terms

• Endocrine Disease
• Endocrine Diseases
• Endocrine System Diseases
• Pheochromocytoma

• NCT number: NCT00004847
• Study type: Interventional
• Source: National Institutes of Health Clinical Center (CC)
• Contact: Alberta Derkyi, C.R.N.P.
• Phone: (301) 827-3355
• Email: alberta.derkyi@nih.gov
• Status: Recruiting
• Phase: Phase 1
• Start date: March 22, 2000
• Completion date: November 30, 2048