*Welcome to the OutUK series looking at gay men and their health brought to you in association with the NHS* website.**
	Each week we'll tackle a different topic in our A to Z of Gay Health. We'll have features and advice on everything from relationships, sexual health, mental and physical conditions and how to stay fit. You can follow any of links provided below for more information direct from the NHS website, or see this week's feature L: Laxatives.

Neuroendocrine Tumours

A neuroendocrine tumour is a rare tumour that can develop in many different organs of the body. It affects the cells that release hormones into the bloodstream (neuroendocrine cells).

Symptoms of neuroendocrine tumours

The 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 or tummy 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 and heart problems.

Causes of neuroendocrine tumours

The cause of neuroendocrine tumours is not fully understood.

However, your chance of developing a tumour is increased if you have 1 of the following inherited conditions:

multiple endocrine neoplasia type 1 (MEN1)
neurofibromatosis type 1
Von Hippel-Lindau syndrome (VHL)

Diagnosing neuroendocrine tumours

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 your veins and a special camera is used to highlight any cancerous cells

Treatment for neuroendocrine tumours

How a neuroendocrine tumour is treated will depend on your individual circumstances, such as:

where the tumour is
how advanced your condition is
your overall health

Unfortunately, many people are only diagnosed after the tumour has spread to other parts of the body.

However, it may still be possible to use surgery to remove the tumour. If surgery cannot completely cure your condition, it may be used to help reduce and manage any symptoms.

Medicine called somatostatin analogues, such as octreotide or lanreotide, may be recommended. They stop your body producing too many hormones, and can reduce the severity of your symptoms and slow the condition's progression. You'll have an injection, usually once every 28 days.

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

There are also other treatments - including everolimus, sunitinib and lutetium - that can be used to treat some neuroendocrine tumours in adults if:

they cannot be fully removed using surgery
they've spread

Everolimus is taken as a tablet, sunitinib is taken as a capsule and lutetium is given into a vein.

For more information, see:

OutUK's A to Z of Gay Health continues and you can read this week's feature L: Laxatives. We have covered many subjects in this series and you can catch up with all of our Previous A to Z Features. If you want to find out more about this particular topic you can visit the Original article on the NHS website. If you are worried by any aspect of your health make sure you go and see your doctor or book an appointment at your local clinic.
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