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Signs and symptoms of neuroendocrine cancer

A sign is something that can be observed and recognized by a doctor or healthcare professional (for example, a rash). A symptom is something that only the person experiencing it can feel and know (for example, pain or tiredness). Signs and symptoms of neuroendocrine cancer may vary depending on the type and location of the tumour, its rate of growth and the type of hormoneshormonesA substance that regulates specific body functions, such as metabolism, growth and reproduction. it releases.

Neuroendocrine cancer may not cause any signs or symptoms in its early stages because the tumour may be small, slow-growing or non-functional (it doesn’t produce hormones). Symptoms appear once the tumour grows into surrounding tissues and organs or starts to produce hormones. Early symptoms may be vague and non-specific, which makes neuroendocrine cancer hard to diagnose.

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Late signs and symptoms

Late signs and symptoms occur as the cancer grows larger or spreads to other parts of the body, including other organs. Examples of late symptoms related to neuroendocrine tumour size or spread include:

  • Large neuroendocrine tumours of the airway (the tubes that air flows through to reach the lungs, including the larynx, trachea and bronchi) may cause difficulty breathing.
  • Pancreatic neuroendocrine tumours in the head of pancreas may block the bile duct, causing jaundicejaundiceA condition in which the skin and whites of the eyes become yellow and urine is dark yellow..
  • Neuroendocrine tumours or cancers can sometimes cause complications due to a reaction around the tumour that causes scar tissue to form. Scarring around intestinal neuroendocrine tumours may cause blockage in the intestine.

Functional neuroendocrine cancers produce hormones. Symptoms of these cancers are related to the specific action of the hormone produced. For example:

  • Too much insulin produced by an insulinoma will result in low blood sugar levels (hypoglycemia), causing sweating, dizziness, fatigue and fainting.
  • Most pheochromocytoma tumours overproduce the hormones epinephrine and norepinephrine. Too much of these hormones can cause high blood pressure and palpitations, which may be life-threatening if left untreated.
  • Rarely, paragangliomas may produce too much epinephrine and norepinephrine.
  • Too much serotonin causes carcinoid syndrome. If left untreated, too much serotonin can cause fibrosis of the heart valves, leading to carcinoid heart disease.

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Carcinoid syndrome

Carcinoid syndrome is a group of symptoms linked to too much serotonin released by one type of neuroendocrine tumour. Carcinoid syndrome affects approximately 10% of people with neuroendocrine tumours. Symptoms include:

  • diarrhea
  • flushing of the skin
  • wheezing and asthma-like symptoms
  • palpitations
  • swelling of the face
  • loss of appetite
  • weight loss
  • abdominal discomfort that comes and goes

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Carcinoid crisis

Carcinoid crisis is caused by a sudden release of too much serotonin hormone. It is a severe episode of intense flushing, diarrhea, wheezing, palpitations and extreme changes in blood pressure. It may be spontaneous or triggered by anesthesia, chemotherapy or surgery. It can be life-threatening. Drugs like octreotide, which act like somatostatin to prevent the tumour from producing hormones, have significantly improved treatment of carcinoid crisis.

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