The short answer
A pheochromocytoma and paraganglioma evaluation may include hormone tests, imaging, genetic assessment, and pathology when appropriate. The goal is to confirm the exact diagnosis and gather information that changes care.
Evaluation may include hormone tests, imaging, genetic assessment, and pathology when appropriate.
Not every person needs every possible test.
Planning may depend on location, hormone secretion, inherited risk, spread, symptoms, and resectability.
A specialist review can clarify an uncommon or unexpected diagnosis.
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The full explanation.
What brings it to light
About half of people with a pheochromocytoma or paraganglioma have no symptoms at all. The tumor is often found by chance, during a scan for something else. When symptoms occur, they come from extra adrenaline-like hormones called catecholamines. These can cause high blood pressure that comes in sudden spells, headaches, sweating, a racing heart, tremor, and pale skin. Symptoms often get triggered by exercise, stress, surgery, or certain foods.
The tests that confirm it
Blood or 24-hour urine tests measure catecholamines and related substances called metanephrines. A blood test called plasma-free metanephrines is highly sensitive. It catches nearly all true cases, though it can also flag some false alarms that need follow-up. Levels two to three times above normal usually point to a true, symptom-causing tumor. CT or MRI of the belly and pelvis then locates the tumor itself. A specialized scan can help too. It uses a tracer called MIBG, or a newer one called DOTATATE. This matters when there may be more than one tumor, or cancer is suspected.
Why genetic testing matters here
About one in three of these tumors is linked to an inherited gene change. That is far more than in most cancers. Because of this, genetic testing is recommended for anyone under 40, anyone with tumors in more than one place, and anyone with a family history. A positive result affects not just your own follow-up care, but whether close relatives should be tested too.
What a high hormone level does and doesn't tell you
An elevated metanephrine level confirms the tumor is actively producing hormones. It does not, by itself, say whether the tumor is cancerous. That distinction often depends on whether the tumor has spread. This may be seen on imaging, or found only later. These tumors can look similar under a microscope, whether they behave in a benign or cancerous way.
Why blood pressure control comes before surgery
If surgery is planned, you will likely start a blood-pressure medicine first. It is called an alpha-blocker, and usually starts one to three weeks before surgery. This step matters for safety. Operating on an unprepared tumor can trigger a dangerous surge in blood pressure during surgery.
What to ask your team
- Are my hormone levels high enough to explain my symptoms?
- Should I have genetic testing, and what would a positive result mean for my family?
- Does imaging suggest one tumor or more than one?
- How long before surgery will I need blood-pressure medicine first?
- Is there any sign this tumor has spread?
When to get help sooner
- Call 911 or go to an emergency department if a pounding headache, chest pain, or a racing and irregular heartbeat comes on hard and fast. A surge of hormone can raise blood pressure enough to cause a heart attack or stroke.
- Call 911 or go to an emergency department if you have weakness on one side, trouble speaking, or a sudden change in vision during one of these spells.
- Call your care team the same day if your home blood pressure readings climb well above the range they set for you, or if spells of drenching sweat, pallor, and shaking start happening more often while you wait for surgery.
- Call your care team within a day or two if the alpha-blocker leaves you dizzy or faint on standing. The dose is meant to be adjusted, not endured.
Sources
Words to know
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Common questions
What symptoms do these tumors cause?
About half of people have no symptoms at all, and the tumor is often found by chance during a scan for something else. When symptoms do occur they come from extra adrenaline-like hormones called catecholamines. They can include high blood pressure in sudden spells, headaches, sweating, a racing heart, tremor and pale skin, and are often triggered by exercise, stress, surgery or certain foods.
Which tests confirm it?
Blood or 24-hour urine tests measure catecholamines and related substances called metanephrines. Plasma-free metanephrines is a highly sensitive blood test that catches nearly all true cases, though it can flag false alarms that need follow-up. Levels two to three times above normal usually point to a true, symptom-causing tumor, and CT or MRI of the belly and pelvis then locates it.
Why is genetic testing recommended here in particular?
About one in three of these tumors is linked to an inherited gene change, which is far more than in most cancers. Testing is recommended for anyone under 40, anyone with tumors in more than one place, and anyone with a family history. A positive result affects your own follow-up care and whether close relatives should be tested too.
Does a high hormone level mean the tumor is cancerous?
No. An elevated metanephrine level confirms the tumor is actively producing hormones, but it does not say whether the tumor is cancerous. That distinction often depends on whether the tumor has spread, which may be seen on imaging or found only later. These tumors can look similar under a microscope whether they behave in a benign or a cancerous way.
Why do I need blood-pressure medicine before surgery?
If surgery is planned you will likely start an alpha-blocker, usually one to three weeks beforehand. This step is about safety. Operating on an unprepared tumor can trigger a dangerous surge in blood pressure during the operation.
Questions to ask your doctor
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Sources last checked: 2026-08-11 what this meansLast updated: 2026-08-11Next planned review: 2027-07-22
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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