Neuroendocrine tumor

Neuroendocrine tumors (NETs) are neoplasms that starts from cells of the endocrine (hormonal) and nervous systems.

Neuroendocrine tumor
Micrograph of a neuroendocrine tumor. H&E stain.
Medical specialty	Endocrine oncology

Many are benign, while some are malignant. They most commonly occur in the intestine, where they are often called carcinoid tumors, but they are also found in the pancreas, lung and the rest of the body.

Symptoms

The signs and symptoms of a neuroendocrine tumour depend on where in the body it is and what hormones it produces. For example, a tumour in the digestive system (gastrointestinal neuroendocrine tumour) may cause:

• diarrhoea
• constipation
• stomach pains

A tumour in the lung (pulmonary neuroendocrine tumour) may cause:

• wheezing or a persistent cough.

Some tumours may lead to abnormally large amounts of hormones being released into the bloodstream. These are known as "functioning tumours" and can cause symptoms such as:

• diarrhoea
• flushing
• cramps
• wheezing
• low blood sugar (hypoglycaemia)
• changes in blood pressure
• heart problems

Diagnosis

Many tests can be used to diagnose neuroendocrine tumours, including blood tests, urine tests, scans and a biopsy (where a small tissue sample is taken for closer examination).

Types of scans used include:

• ultrasound
• CT (computerised tomography)
• MRI (magnetic resonance imaging)
• PET (positron emission tomography)
• octreotide scans – where slightly radioactive liquid is injected into the veins and a special camera is used to highlight any cancerous cells

Other websites

• The Neuroendocrine Cancer Awareness Network (NCAN)