In June 2014, the Endocrine Society published its first clinical practice guideline for pheochromocytoma and paraganglioma, rare but sometimes dangerous tumors.
Pheochromocytoma is a rare tumor arising from chromaffin cells of the adrenal gland. Paraganglioma is a tumor derived from extra-adrenal chromaffin cells, usually in the thorax, abdomen or pelvis.1
Pheochromocytomas and paragangliomas (PPGL) are usually benign but have malignant potential. These tumors commonly produce one or more catecholamines. Untreated PPGL leads to significant cardiovascular morbidity and mortality.1
“These are the first practice guidelines put out by the Endocrine Society for this very rare disorder. Only a few people in the world have experience dealing with PPGL, so these guidelines can help fill in the knowledge gaps,” said William F. Young Jr., MD, professor and chair of endocrinology, diabetes, metabolism and nutrition at the Mayo Clinic in Rochester, Minn. Dr. Young is also an author of the guidelines.
Why the Guidelines Are Important
The guidelines were created for several reasons. PPGL is a rare disorder, with an incidence of less than 0.6%. However, autopsy studies suggest that these tumors may be missed.
In children with high blood pressure (BP), PPGL may be responsible for close to 2% of cases, and at least one-third of patients are now found to have inherited mutations for PPGL. Therefore, genetic testing for family members may now result in earlier diagnosis.1
“A missed diagnosis or poor management can be tragic. A missed PPGL may become malignant and metastatic. At the end of the guidelines, we stress the importance of getting these patients to a treatment center experienced in managing [PPGL],” Dr. Young said.
“There is not all that much that is new in the guidelines. It is generally what we have been doing,” said Stuart Alan Weinerman, MD, chief at Long Island Jewish Medical Center, and assistant professor of endocrinology at Hofstra North Shore-LIJ School of Medicine in Long Island, N.Y.
“The value of these evidence-based guidelines is that they get everybody on the same page. That means improved quality of care.”
Most doctors know the symptoms of PPGL, which include episodes of high BP, pounding heartbeat, extreme sweating, headache and pallor. The disease usually develops in people aged 20 to 50 years.2The guidelines recommend initial testing for PPGL with plasma free or urinary fractionated metanephrines.1
“This is not new. We have known these are the best tests for screening for about 14 years,” said Dr. Young.
The guidelines also recommend imaging studies if biochemical evidence is confirmed. They suggest CT scan as the best first choice over MRI.
“This is one of the few new wrinkles,” Dr. Weinerman said. “In the past many doctors would do an MRI first.
The guidelines do, however, recommend MRI as an imaging study in patients with metastatic disease.1