About malignant carcinoid syndrome

What is malignant carcinoid syndrome?

Malignant carcinoid syndrome is characterized by a variety of signs and symptoms. Carcinoid tumors are neuroendocrine tumors that develop from primitive stem cells that can give rise to a variety of cell types.

  • When a rare malignant tumor called a carcinoid tumor secretes particular chemicals into your bloodstream, it causes a variety of indications and symptoms. The most common areas for carcinoid tumors, which are a form of neuroendocrine tumor, are the gastrointestinal system and the lungs. 
  • The small intestine and appendix are the most prevalent areas for carcinoid tumors, while the lung accounts for some of all cases. The rectum, colon, pancreas, stomach, ovary, kidney, prostate, breast, and other organs are also affected. 
  • Malignant carcinoid syndrome is most common in persons who have advanced carcinoid tumors. The syndrome is usually treated by treating cancer. 
  • Malignant carcinoid syndrome does not occur in persons who do not have a liver tumor because the serotonin generated by the tumor is broken down to an inert chemical.

A cure may not be achievable because most carcinoid tumors do not develop Malignant carcinoid syndrome until they are advanced. Medications may be prescribed to help you cope with the symptoms of carcinoid syndrome and make you more comfortable.

What are the symptoms for malignant carcinoid syndrome?

Though the symptoms of malignant carcinoid syndrome depend on the type of chemical that the carcinoid tumor secretes into your bloodstream, the below-mentioned are common signs and symptoms that occur.

  • Skin flushing: Skin flushing (sudden reddening of cheeks), can be a common symptom. Your face and upper chest skin may feel hot and change color, ranging from pink to purple. Flushing attacks can last anywhere from a few minutes to many hours or more.
  • Diarrhea: Carcinoid syndrome patients may experience frequent, watery feces that are sometimes accompanied by abdominal pains.
  • Breathing problems: Wheezing and shortness of breath, which are asthma-like signs and symptoms, may occur at the same time as skin flushing.
  • Edema: Swelling of the feet and legs. This could be a sign that you're suffering from heart failure.

Other symptoms of malignant carcinoid syndrome include: 

  • Abdominal pain.
  • Loss of weight.
  • Change in bowel habits, especially blood in bowel movements.
  • Feeling faint or dizzy. This could indicate low blood pressure.
  • You have the sensation that your heart is racing.
  • Fatty stool with a foul odor.
  • Sudden blood pressure dropping.
  • Small blood vessels that look widened on the face.

What are the causes for malignant carcinoid syndrome?

The exact cause of malignant carcinoid syndrome is unknown, but it is thought to be related to the spread of cancerous cells to the liver. The most common type of cancer associated with malignant carcinoid syndrome is small cell lung cancer. 

  • The mutations that can rise to carcinoid tumors are unknown to doctors. They are aware, however, that carcinoid tumors are caused by neuroendocrine cells.
  • Neuroendocrine cells can be found in all of the body's organs. Some nerve cell functions and some hormone-producing endocrine cell functions are performed by them. Histamine, insulin, and serotonin are some of the hormones generated by neuroendocrine cells.
  • Carcinoid tumors can release hormones that cause the lining of heart chambers, valves, and blood arteries to thicken. Leaky heart valves and cardiac failure may result, necessitating valve replacement surgery. 
  • Among other indications and symptoms, malignant carcinoid syndrome produces redness or a feeling of warmth in your face and neck (skin flushing), recurrent diarrhea, and difficulties in breathing.
  • In addition, when your Gastrointestinal (GI) system creates and delivers too many hormones to your liver, you get malignant carcinoid syndrome.
  • Hormones can flood your system if your GI tract generates too much or if you have a NET in your liver that prevents it from digesting and eliminating them, creating carcinoid syndrome.

What are the treatments for malignant carcinoid syndrome?

Treatments for malignant carcinoid syndrome include:

  • Surgery: Surgery is the most common treatment for malignant carcinoid syndrome. The goal of surgery is to remove the cancerous tumor from the body. This can be done through various surgical procedures, such as bowel resection, gastrectomy, or liver transplant. Surgery is often the most effective treatment option for this condition.
  • Radiation therapy: This is another common treatment for malignant carcinoid syndrome. This treatment can be given externally, through a machine that directs the energy waves at the cancerous tumor, or internally, through a radioactive implant placed directly into the tumor. Radiation therapy is often combined with surgery to treat malignant carcinoid syndrome.
  • Chemotherapy: Thistype of treatment uses drugs to kill cancer cells. Chemotherapy can be given intravenously, orally, or topically. The type of chemotherapy that is most effective for treating malignant carcinoid syndrome. Chemotherapy is often combined with other treatments, such as surgery or radiation therapy.
  • Radiofrequency: Radiofrequency ablation uses a needle to give heat to cancer cells in the liver, forcing the cells to die. Cryotherapy works in a similar way, but it freezes the tumor.


PRRT: Peptide Receptor Radionuclide Therapy (PRRT) is a treatment that combines a medicine that targets cancer cells with a radioactive material that destroys them.

What are the risk factors for malignant carcinoid syndrome?

Malignant carcinoid syndrome symptoms can be experienced by people who have cancerous tumors in their digestive system. The tumors release chemicals into the bloodstream that can cause various symptoms, including flushing, diarrhea, and wheezing. In some cases, the syndrome can also cause heart problems. 

Risk factors of malignant carcinoid syndrome:

  • Age: The average age of diagnosis for malignant carcinoid syndrome is between 50-60 years old. According to experts, carcinoid tumors are thought to affect four out of every 100,000 adults. As carcinoid tumors in children and young adults are so uncommon, there is limited information about how many young people are affected.
  • Gender: There is a slight predominance of females over males diagnosed with malignant carcinoid syndrome.
  • Family history: Having a family member with malignant carcinoid syndrome or any other neuroendocrine tumor might increase the risk of you getting it.
  • Smoking: Cigarette smoking has been linked to an increased risk of developing malignant carcinoid syndrome.
  • Race: Caucasians are more likely to be diagnosed with malignant carcinoid syndrome than any other race.
  • Stomach carcinoid tumors are more common in those who have disorders that harm the stomach and diminish stomach acid levels (such as pernicious anemia).

Is there a cure/medications for malignant carcinoid syndrome?

The onset of malignant carcinoid syndrome indicates that cancer has already spread, most commonly to the lungs or liver. If your doctor detects a tumor early enough, it may be possible to remove it. 

Medications for malignant carcinoid syndrome that can help:

  • Immunotherapy strengthens your body's defenses. Doctors might inject drugs that help your immune system kill cancer cells.
  • Injections of the drugs octreotide (Sandostatin) and lanreotide (Somatuline Depot) can help with malignant carcinoid syndrome symptoms such as skin flushing and diarrhea. To manage diarrhea induced by carcinoid syndrome, a medication called Telotristat (Xermelo) can be used with these drugs.
  • PRRT (Peptide Receptor Radionuclide Therapy) is a cancer-fighting treatment that mixes a drug with a radioactive element that kills cancer cells.
  • Stopping blood supply to liver tumors helps healthy liver cells rely on blood from other blood veins to survive.
  • Chemotherapy is a type of cancer treatment that employs the use of powerful chemicals to kill cancer cells. Chemotherapy medications can be delivered intravenously (via a vein) or orally (in pill form), or both.
  • Currently, octreotide is the medicine of choice for treating carcinoids and associated malignant diseases all over the world. Because of its short half-life, somatostatin is rarely used. Antiproliferative medications may be effective for symptom relief in patients with diffuse metastases.

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