Neuroendocrine tumours

What causes neuroendocrine tumours (NETs) is not known. These tumours can affect people of any age, including children, but most people are diagnosed around 50 or 60 years old.

About 1 in 20 (5%) of NETs occur in people with a hereditary (genetic) condition. People with a rare genetic condition called multiple endocrine neoplasia 1 (MEN1) have a higher risk of developing NETs.

Other rare genetic conditions that can raise the risk of NETs are:

• von Hippel-Lindau (VHL) disease
• tubular sclerosis (TSC)
• neurofibromatosis (NF)

NETs may occur at a younger age in people with these hereditary conditions. If you are diagnosed with a NET at a younger age, you may be offered genetic testing.

You may also be offered testing if you have a family history of NETs, or other symptoms that could be caused by one of these hereditary conditions.

If you have neuroendocrine tumours, you'll usually start by seeing your GP. If they're not sure what's causing your symptoms, they'll refer you to a specialist at the hospital.

At the hospital, the doctor will ask about your general health and any past medical problems. They'll then examine you and talk you through the tests you may need.

Sometimes a NET is found on a scan you're having for a completely different reason.

You may have some of the following tests.

If you have a NET, the levels of certain chemicals in your blood may be higher than normal. These are mainly:

• serotonin
• 5HIAA
• a protein called chromogranin A (CgA)

Serotonin is a natural chemical made by the body. It carries messages between different parts of the brain and helps control things like your sleep, mood and appetite.

You'll need to give blood samples so these levels can be checked, and you may be asked to fast (not eat) beforehand. You may also have a blood test to check for hormones released by some NETs.

You'll also have general blood tests to count the number of healthy blood cells you have. This is called a full blood count, or FBC.

You may have other blood tests to check:

• how well your kidneys and liver are working
• your hormone levels
• your level of vitamin B12

You may be asked to collect all the urine you pass over a 24-hour period, so your doctor can test it for 5HIAA. This substance is made from serotonin by the liver and then leaves the body in your urine. Certain foods, drinks and medicines can raise your 5HIAA levels, so you may need to avoid these for a few days before and during the collection. Your doctor or nurse will explain more about this.

An ultrasound scan uses sound waves to build a picture of the inside of your body. You'll usually need to avoid eating or drinking for at least 6 hours beforehand. You may also have an ultrasound of your heart, known as an echocardiogram.

A CT scan uses X-rays to build a 3D picture of the inside of your body.

An MRI scan uses magnetism to build a detailed picture of areas inside your body.

Nuclear medicine scans use a small amount of a radioactive substance called a tracer, which shows up on the scan pictures. The amount of radioactivity involved is low, roughly the same as you'd get from an ordinary X-ray.

During a biopsy, doctors take a small piece of tissue, or a sample of cells, from the tumour and examine it under a microscope. You'll be given a local anaesthetic to numb the area beforehand. Sometimes a general anaesthetic is used instead, depending on where the NET is in your body.

Waiting for test results can be a hard time. Macmillan Cancer Support have more information that can help.

Further tests

Depending on the type of NET you have, your doctor may want to arrange other tests.

A bone scan looks for any unusual areas in the bone. A mildly radioactive substance is injected into a vein, and a scan of your bones is taken 2 to 3 hours later.

You may also have an endoscopy, where a thin, flexible tube with a camera at the end is used to look inside the gullet (oesophagus), stomach, small bowel or large bowel.

Your doctor or nurse will explain the test to you and why you need it.

Macmillan Cancer Support have more information on cancer tests and on waiting for results.

Staging and grading of neuroendocrine tumours (NETs)

The results of your tests help your doctors understand more about the size and position of the cancer, and whether it has spread. This is called staging.

A doctor works out the grade of the cancer by looking at how the cancer cells appear under the microscope. This gives an idea of how quickly the cancer is likely to grow or spread.

Knowing the stage and grade helps your healthcare team plan the treatment that's right for you.

Treatment for neuroendocrine tumours (NETs)

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).They’ll discuss the results of your tests to plan your treatment. They’ll look at factors including:

• where the NET started
• the size of the tumour and whether it has spread (its stage)
• whether you have symptoms of carcinoid syndrome or the over-production of other hormones
• the appearance of the cells under a microscope (its grade)

Your doctor, cancer specialist or nurse will explain the different treatments and their side effects. They’ll also talk to you about things to think about when making treatment decisions.The main treatment is surgery to remove the tumour. The aim of this is to cure the cancer. If surgery can’t completely remove the NET, treatment will aim to relieve symptoms and improve quality of life.

Surgery for NETs

Your team will plan your operation carefully. They’ll explain:

• the surgery
• the possible side effects
• what to expect

If you have a functioning NET, there’s a risk that an operation will cause carcinoid crisis. Your doctors will try to prevent this and monitor you during treatment.

Macmillan Cancer Support have more information about preparing for surgery.

Localised and low-grade NETs may be completely removed with surgery. The aim of the operation is to cure the cancer.

Sometimes, this type of operation is also possible if there has been only limited spread. This is called regional spread.

Depending on where the NET is, it may be possible to remove it during an endoscopy.

An operation to remove all of the cancer may sometimes be possible for NETs that have spread to the liver. This will depend on where the tumours are in your liver. Your doctors will discuss this with you.

If it’s not possible to completely remove the tumour, doctors may try to remove as much as possible. This is called debulking. It can improve your symptoms by relieving pressure on other parts of the body. It can also help to reduce symptoms caused by the over-production of a hormone.

Surgery can also help relieve symptoms of a NET that has spread to more distant sites in the body (metastatic). For example, if a tumour is blocking the small bowel, surgery can remove it or bypass the blockage.

Other treatments for NETs

There are other treatment options you may have.

Some NETs are slow-growing and may not change for months or years. If a NET spreads but isn’t causing symptoms, you may not need treatment straight away.

Your doctor will monitor you with regular check-ups. If symptoms develop, you’ll have the option of treatment.

Somatostatin analogues are drugs that treat the symptoms of carcinoid syndrome. They work by blocking the hormones the tumour makes. They may also control the growth of NETs. You may be given them along with other treatments.

Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. You may have chemotherapy to treat NETs that have spread.

The type of chemotherapy you’ll have depends on where the NET started in the body.

Chemotherapy treatments that can be used for NETs include:

• capecitabine and temozolomide (CAPTEM)
• FOLFOX
• streptozocin and fluorouracil (5FU)
• etoposide and cisplatin (EP)
• carboplatin and etoposide

Targeted therapies

Targeted therapies are anti-cancer medicines that interfere with how cancer cells grow and divide. The 2 main targeted therapy drugs used are:

• sunitinib (Sutent®)
• everolimus (Afinitor®)

You take these drugs as capsules or tablets. Other targeted therapies may be available as part of a clinical trial.

Interferon is a drug that can treat the symptoms of NETs. It may also control how the tumour grows.

Interferon is a protein that you naturally have small amounts of in your body.

If you have it as a drug, it can stimulate the body’s immune system to destroy cancer cells. You’ll have it as an injection under the skin.

Radiotherapy uses high-energy x-rays to destroy cancer cells, while doing as little harm as possible to normal cells. You may have radiotherapy if it’s not possible to remove the tumour with surgery, or if it has already spread.

You may have radionuclide therapy to relieve symptoms of carcinoid syndrome and control the growth of NETs. This therapy uses a radioactive substance called a radionuclide. It’s injected into the bloodstream.

Treatments for NETs in the liver

Treatments that directly target the liver can sometimes treat NETs in the liver.

A hepatic artery embolisation can sometimes shrink NETs in the liver. It can also relieve the symptoms of carcinoid syndrome. Hepatic artery embolisation works by reducing blood flow to the tumours. Tumours need a blood supply to survive.

Radiofrequency ablation (RFA) can treat NETs in the liver. It uses laser or radio waves to destroy the cancer cells by heating them to high temperatures.

Selective internal radiation therapy is a type of cancer treatment that uses tiny radioactive beads. It can treat NETs that are found in the liver.

Cancer research trials

Cancer doctors use cancer research trials to assess new treatments. Current studies are looking at new treatments for NETs.

Your doctor may ask you to take part in a cancer research trial. They’ll discuss the treatment with you, so you understand the trial and what it means to take part.

After neuroendocrine tumours (NETs) treatment

You have regular follow-up appointments after treatment. You may be monitored with blood tests and scans.

After treatment, some people may be cured of NETs. Others may continue to have treatment when they need it to help keep it under control.

If the cancer is advanced, there are different things that can be done to control the symptoms.

Macmillan Cancer Support have more information on advanced cancer.

Your feelings after treatment

You may have many different emotions, including anxiety, anger and fear. These are all normal reactions.

It may help to get support from family, friends. Organisation, like Neuroendocrine Cancer UK can also help. They can give you information about counselling in your area.

Macmillan Cancer Support also has further information to support you. You can:

• phone the Macmillan Support Line on 0808 808 00 00
• chat to Macmillan specialists online
• use the neuroendocrine cancer forum – you can talk to others affected by neuroendocrine cancer, ask questions and share your experience

Don’t include personal information e.g. name, location or any personal health conditions.

Even if your lifestyle is already fairly healthy, treatment can be a good moment to make a few positive changes. For example, if you smoke or drink alcohol, it helps to cut down on alcohol or avoid smoking altogether.

Eating well and staying as active as you can will support your overall health and wellbeing, and it can also help your body recover. If you find eating difficult after treatment, your dietitian can help you work through it.