What Is Carcinoid Syndrome?
Carcinoid syndrome is a condition in
which a carcinoid tumor secretes chemicals into your bloodstream. The tumors
are usually located in your gastrointestinal tract or lungs.
Carcinoid syndrome is very rare. It
occurs most often in patients whose cancer has spread (metastasized) to their
liver or lungs.
Treatment for carcinoid syndrome
involves treating the cancer, which may include chemotherapy or surgery to
remove any tumors. With complete removal of the tumors, your long-term outlook
is very good.
Unfortunately, since most cases of
carcinoid syndrome develop in the advanced stages of cancer, full recovery may
not be possible. Still, your doctor can prescribe medications to relieve some
of the specific symptoms of your condition.
Causes of Carcinoid
Carcinoid syndrome occurs when you
have a carcinoid tumor that is secreting chemicals, such as serotonin, into
your bloodstream. The chemicals cause your blood vessels to dilate, or open up.
Most carcinoid tumors do not secrete chemicals that cause this condition. If a
carcinoid tumor does secrete chemicals, the liver often neutralizes them before
they can spread through your body.
Typically, carcinoid syndrome is a
sign that your cancer has already spread to your liver or lungs. People with
carcinoid tumors of the small intestine often already have metastatic disease
in the lymph nodes or liver.
The cause of these tumors is unknown.
It’s likely that carcinoid tumors form in your gastrointestinal tract, which
includes your appendix, stomach, small intestine, colon, and rectum, or they
occur in your lungs.
Symptoms of Carcinoid
On their own, carcinoid tumors often
produce no symptoms. The symptoms of carcinoid syndrome vary, depending on the
particular chemicals that are secreted into your blood.
Symptoms may include:
- flushing (your
face and chest will feel hot and the skin will appear red, pink, or purple,
lasting from a few minutes to several hours)
- skin lesions
or purple spider veins on the upper lip and nose
- shortness of
breath or wheezing
heartbeat or heart palpitations
- low blood
Symptoms can be triggered or made
worse by certain activities, such as stress or heavy exercise. Drinking alcohol
or eating rich foods, such as chocolate, red wine, or blue cheese, can also
worsen flushing and other symptoms of carcinoid syndrome.
If you have symptoms of carcinoid
syndrome, see your doctor.
How Carcinoid Syndrome Is
Usually, your doctor will discover
this condition while performing other tests, such as a pre-surgery blood test.
They’ll make a diagnosis based on your
symptoms, a physical exam, and additional tests. These extra tests include:
- blood tests to
check the levels of certain chemicals, such as the protein chromogranin, which
can come from carcinoid tumors
- urine tests to
see how your body is processing serotonin
- imaging tests,
such as an MRI or CT scan
Treating Carcinoid Syndrome
Treating carcinoid tumors will
decrease your chances of developing carcinoid syndrome. If you do develop the
syndrome, your doctor will first try to treat the cancer and then address your
Depending on your situation, your
doctor may choose to surgically remove the tumors or to shrink them using
chemotherapy. They may also prescribe medications that slow the tumors’ growth
or prevent them from releasing harmful chemicals.
Other treatment options include:
- hepatic artery
embolization: a procedure in which tumors are cut off from their blood supply
ablation: a procedure in which cancer cells are killed using heat
- cryotherapy: a
treatment that freezes cancer cells
Complications of Carcinoid
If the tumor isn't removed, carcinoid
syndrome can lead to several life-threatening complications. Carcinoid heart
disease may cause your heart valves to thicken and leak. This can lead to
fatigue, shortness of breath during physical activity, and possible heart
Carcinoid crisis is another
potentially fatal complication marked by extremely low blood pressure,
flushing, breathing difficulties, and confusion. Anesthesia before surgery can
If your tumors are located in the
lymph nodes near your small intestines, you’re at a higher risk for developing
a bowel obstruction. Symptoms of a bowel obstruction include cramping,
abdominal pain, and vomiting. Carcinoid syndrome can also cause bleeding in
your gastrointestinal tract.
The low blood pressure caused by
carcinoid syndrome may also increase your risk of falling down and injuring
Long-Term Outlook for
Your long-term outlook depends on the
specifics of your condition and treatment. Carcinoid syndrome can be cured if
the tumor is completely removed through surgery.
If you have carcinoid syndrome, you
can take certain steps to reduce your symptoms. Try to avoid:
- triggers that
cause flushing and other symptoms, particularly foods high in tyramine (aged
cheeses, avocado, and processed foods)
- large meals
Selective serotonin reuptake
inhibitors, such as fluoxetine (Prozac) and paroxetine (Paxil), can make your
symptoms worse. If you take these medications, ask your doctor if there are
safer alternatives. Never stop taking medications without consulting your
If you suffer from diarrhea, ask your
doctor if you should take a multivitamin supplement to replace lost nutrients.
It can be helpful to talk to other
people who are coping with the same condition. Ask your doctor or hospital for
information about support groups in your area.