Selective internal radiation therapy (SIRT)

Tiny radioactive beads are injected into the bloodstream. They stick permanently in the small blood vessels in and around the liver tumour. The beads give off radiation, which damages the cancer cells.

The radioactivity of each bead only affects tissue that is very nearby. This means cancer cells near the beads will be most affected. Some healthy cells may also be affected. Your team will decide how many radioactive beads to inject to try to reduce the risk of damage to healthy cells.

The beads lose their radioactivity quickly and are most effective in the first few days. They stay in the body permanently, but this does not cause any problems.

Your doctor will arrange tests before you have treatment. These help your team to decide whether you will benefit from SIRT. The tests also help plan your treatment.

A sample of your blood is taken to check:

• the levels of different types of cells in your blood – this is called a full blood count
• how well your kidneys and liver are working
• how quickly your blood clots.

If you have bowel cancer, your blood may also be tested for a protein, or tumour marker called carcinoembryonic antigen (CEA). Some people with bowel cancer have higher levels of this protein. So, doctors may check this regularly to see how well a treatment for bowel cancer is working.

If you are having SIRT for hepatocellular carcinoma, your blood may be tested for a tumour marker called alpha fetoprotein (AFP).

We have more information about blood tests.

An angiogram is a test that uses x-rays to look at blood vessels. A planning angiogram shows the blood supply to your liver. This may also be called a pre-SIRT angiogram. It helps your doctor see where the SIRT beads would go when they are injected.

You have this test in the x-ray (radiology) department of the hospital. You may be asked not to eat or drink anything for several hours before. Your team will also give you instructions about any medication you usually take. This includes drugs that thin your blood, such as aspirin or warfarin.

You will have a local anaesthetic injection to numb the skin on one side of the groin or wrist. The doctor then makes a small cut in the skin. They gently put a thin, flexible tube called a catheter into a blood vessel in the groin or wrist. The catheter is guided up the blood vessel to the liver.

The doctor injects dye into the catheter and takes x-rays to see where the dye goes. This shows where the SIRT beads would travel in the bloodstream. The doctor uses tools through the catheter. Sometimes they may close off any small blood vessels that would take the beads away from the tumour to other parts of the body. This does not harm the areas that are closed off.

The doctor then injects a liquid called a radioactive tracer. After the angiogram, you have a scan that finds this liquid. It shows where the SIRT beads will go to in the liver. It also checks that none would escape from the liver to other parts of the body, such as the bowel or lungs. This helps your doctor know if it is safe for you to have the treatment. If the scan finds tracer outside the liver, you may need another planning angiogram before you have SIRT. You pass the radioactive tracer in your urine (pee). It does not cause damage to you or anyone that you come into contact with.

If the cut was made in the groin, you have to lie flat for a few hours after the angiogram. If the cut was made on the wrist, you can sit up straight away. Try to drink at least 1½ litres (3 pints) of water in the 24 hours after your test. This helps clear the dye from your body.

Your team will tell you what you can and cannot do after the test. Usually, you should:

• not drive for 24 hours after the test
• avoid heavy lifting and vigorous exercise for 3 days.

Your healthcare team will plan your treatment to give you the amount of radiation needed to treat the cancer safely and effectively. But your team are also careful to protect other people around you from radiation. Safety measures may be slightly different in different hospitals. Your team will tell you what to expect.

Almost all the radiation from each SIRT bead is absorbed by the area of the body closest to it. But your body fluids will be slightly radioactive for a time. It is safe for you to be around most other people. But you may have to avoid close contact with children or anyone that is pregnant for a while.

Your team will explain this and any other safety measures you need to know about or follow at home. This may include instructions about:

• using the toilet and cleaning up any spilled body fluids safely
• not sharing a bed or having sex for a few days
• not breastfeeding or using expressed breast milk (milk you have stored to feed your baby later) for a few weeks.

Your team will also give you information to carry with details of your treatment.

We explain the most common side effects of this treatment here. You may get some of the side effects we mention, but you are unlikely to get all of them. These side effects are usually short-term and get better with time.

You may also have some side effects that we have not listed here. Always tell your doctor, nurse or pharmacist about any side effects you have.

Rarely, SIRT can cause side effects that start weeks after treatment. Sometimes these may be serious or need treatment straight away. Your team will explain these to you.

There may be bruising or a small lump where the angiogram catheter went into the groin or wrist. You should let your nurse or doctor know straight away if you notice any:

• bleeding
• redness
• swelling
• discharge
• pain.

You may be given an anti-sickness drug to prevent nausea before you have SIRT. Tell your doctor or nurse if you feel sick after treatment. They can give you tablets to help. Nausea usually only lasts for a few days.

Some people have tummy pain during SIRT. Tell your doctor or nurse about any pain you have during or after treatment. They can give you painkillers to help.

Rarely, some beads may escape from the liver to the stomach or bowel. This can irritate the lining of the stomach or bowel and cause tummy pain or indigestion. You may be given medicine to take regularly. This will help. Tell your doctor or nurse straight away about any pain.

This treatment can cause a high temperature for a few days. Fever is a common side effect of SIRT, but it can also be a sign of infection.

When you are home, contact the hospital straight away on the contact number you have been given if:

• your temperature goes over 37.5°C (99.5°F)
• your temperature goes below 36°C (96.8°F)
• you suddenly feel unwell, even with a normal temperature
• you have symptoms of an infection – this can include feeling shaky, a sore throat, a cough, diarrhoea or needing to pass urine (pee) a lot.

Tiredness can last from a few days up to several weeks after treatment. It is important to get enough rest and eat a balanced diet to help your body recover. Keeping a fatigue diary can help you record your energy levels and plan activities for when you are feeling stronger. We have more information about coping with tiredness.