The neuroendocrine system is made up of nerve and gland cells. It produces hormones and releases them into the bloodstream. NETs can be malignant or benign and are usually slow-growing.

NETs are known as functioning tumours, if they produce hormones that cause specific symptoms. There are a number of different types of NETs:

  • GEP NETs (Gastroenteropancreatic neuroendocrine tumours) – develop in the gut or pancreas
  • GI NETs (Gastrointestinal neuroendocrine tumours) – develop in the digestive system
  • pNETs (Pancreatic neuroendocrine tumours) – develop in the pancreas
  • Pulmonary neuroendocrine tumours develop in the lungs

NETs can also develop in other parts of the body, but this is rare.

Symptoms of neuroendocrine tumours

The symptoms of a neuroendocrine tumour will vary depending on where it is and the hormones it produces e.g. a tumour in the lung may cause a persistent cough or wheezing. Functioning tumours may cause abnormally large amounts of hormones to be released into the bloodstream. This can cause symptoms such as diarrhoea, cramps, wheezing, low blood sugar, blood pressure and heart problems.

If you have any concerns about similar symptoms, it is essential that you see your doctor at once, as the chances of recovery are much higher if cancer is diagnosed early.

How are neuroendocrine tumours diagnosed?

Various tests can be used to diagnose NETs, including blood tests, urine tests, and biopsies.

Different types of scans may also be used including:

  • An ultrasound scan
  • A CT scan
  • An MRI scan
  • A  PET scan
  • An octreotide scan

Treatment of neuroendocrine tumours

Treatment depends on your individual circumstances including your general health, where the tumour is and how advanced your condition is.

Unfortunately, many people are only diagnosed after other parts of their body have been affected. However, it may still be possible to surgically remove the tumour, even if it has spread to other parts of your body. If surgery can’t be used to completely cure your condition, it may be used to help manage and reduce any symptoms that you have.

It may also be possible to shrink the tumour or stop further growth using treatments that block the blood supply to the tumour (embolisation), or chemotherapy, radiotherapy or radiofrequency ablation (where heat is used to destroy the cells).