What is MATRIX?

MATRix is a combination of cancer drugs. It is used to treat primary CNS lymphoma. It may sometimes be used to treat other cancers. It may also be used to harvest stem cells in people having a stem cell transplant.

It is best to read this information with our general information about chemotherapytargeted therapies and the type of cancer you have.

Your cancer team will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

MATRix is named after the initials of the drugs it uses. The drugs are: 

Methotrexate, cytarabine and thiotepa are chemotherapy drugs. Rituximab is a type of targeted therapy called a monoclonal antibody. The drugs used in MATRix can pass through the brain’s protective layer (the blood–brain barrier) into the brain and spinal cord.

More information about this treatment

This information is correct at time of publishing. But sometimes the types of cancer this treatment is used for, or treatment side effects, may change between revision dates.

You can talk to your cancer team if you want more detailed information about this treatment. Or visit the electronic Medicines Compendium (eMC) website, which has patient information leaflets (PIL) for individual drugs.

How MATRIX is given

You usually have MATRix during a stay in hospital.

During your course of treatment, you will meet someone from your cancer team, such as a:

  • cancer doctor
  • chemotherapy nurse or a specialist nurse
  • specialist pharmacist.

This is who we mean when we mention doctor, nurse or pharmacist in this information.

Before or on the day of each treatment, you will have a blood test. This is to check that it is safe for you to have treatment.

You will meet with a doctor, nurse or pharmacist before you have treatment. They will talk to you about your blood results and ask how you have been feeling. If your blood results are okay, the pharmacy team will prepare your cancer drugs.

Your nurse will usually give you anti-sickness drugs before the cancer drugs. You will have your cancer treatment through 1 of the following:  

  • a central line – a fine tube that goes under the skin of the chest and into a vein close by
  • a PICC line – a fine tube that is put into a vein in the arm and goes up into a vein in the chest.

Your cancer team may also give you anti-sickness drugs and other medicines to take home. Take all your capsules or tablets exactly as they tell you to.

Your course of treatment

You usually have up to 4 cycles of MATRix treatment over a few months. Your doctor will talk to you about how many cycles you may have.

A cycle of treatment includes:

  • the days you are given the chemotherapy and targeted therapy drugs  
  • a rest period when you do not have any drugs, to let your body recover.

A cycle of MATRix is usually 21 days (3 weeks). You usually have the MATRix drugs over 5 to 10 days. But you may have them over a longer period.  

On the days you have your chemotherapy drugs, you also have a continuous infusion (drip) of fluids. This helps to reduce the side effects of high-dose methotrexate and keeps you hydrated.

You will also have a drug called folinic acid. This is sometimes called leucovorin or calcium folinate. It also helps reduce the side effects of high-dose methotrexate. You have it regularly until the methotrexate is no longer in your body. You have a blood test to check the level of methotrexate in your body.

Once you have had all the drugs, you have a rest period with no treatment for the remaining days of the cycle. This completes your first cycle of MATRix.

At the end of the rest period, you start your second cycle of MATRix.

About side effects

We explain the most common side effects of this treatment here. We also include some that are less common.

You may get some of the side effects we mention, but you are unlikely to get all of them. And you may have some side effects, including rarer ones, that we have not listed here. 

Always tell your doctor, nurse or pharmacist about any side effects you have. They can give you: 

  • drugs to help control some side effects
  • advice about managing side effects. 

It is important to take any drugs exactly as explained. This means they will be more likely to work for you. 

Serious and life-threatening side effects

Some cancer treatments can cause serious side effects. Sometimes, these may be life-threatening. Your doctor, nurse or pharmacist can explain the risk of these side effects to you.

Contact the hospital

Your doctor, nurse or pharmacist will give you 24-hour contact numbers for the hospital. If you feel unwell or need advice, you can call at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

Side effects while treatment is being given

Some people have side effects while they are having this treatment or shortly after they have it.

Allergic reaction

Some people have an allergic reaction while having this treatment. The first infusion is the most likely to cause a reaction, so it is usually given more slowly than later treatments. Before treatment, you will have medicines to help prevent or reduce any reaction.

Signs of a reaction can include:

  • feeling hot or flushed
  • shivering
  • itching
  • a skin rash
  • feeling dizzy or sick
  • a headache
  • feeling breathless or wheezy
  • swelling of your face or mouth
  • pain in your back, tummy or chest.

Your nurse will check you for signs of a reaction during your infusion. If you feel unwell or have any of these signs, tell them straight away. If you do have a reaction, they can treat it quickly.

Sometimes a reaction happens a few hours after treatment. If you develop any of these signs or feel unwell after you get home, contact the hospital straight away on the 24-hour number.

Always call 999 if swelling happens suddenly or you are struggling to breathe.

Cytarabine syndrome

Cytarabine may cause a reaction 6 to 12 hours after you have it. This is called cytarabine syndrome. Symptoms include:

  • fever
  • aching in the muscles, bones or chest
  • a rash
  • sore eyes.

If you develop any signs or feel unwell after your treatment, tell your doctor or nurse straight away.

Low blood pressure

Your blood pressure may fall while you are having rituximab. If you usually take medicine to lower your blood pressure, your doctor may ask you not to take it for 12 hours before having rituximab.

Sometimes rituximab and thiotepa can make your blood pressure go up. Your nurse will check your blood pressure regularly.

The drug leaks outside the vein

Sometimes cancer drugs that are given into a vein may leak outside the vein. If this happens, some drugs can damage the tissue near the vein. This is called extravasation. Extravasation is not common, but it is important that it is dealt with quickly. If you have any of the following symptoms around the vein during or after your treatment, tell your nurse straight away:

  • stinging
  • pain
  • swelling
  • if you have white skin, the area may become red
  • if you have black or brown skin, the area may become darker.

Common side effects

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If your white blood cell count is low, you may be more likely to get an infection. A low white blood cell count is called neutropenia.

An infection can be very serious when the number of white blood cells is low. Your doctor may give you antibiotics and other drugs to take during this treatment. These may help reduce your risk of getting an infection. 

But it is still important to get any infection treated as soon as possible. If you have any of the following symptoms, contact the hospital straight away on the 24-hour number:

  • a temperature above 37.5°C 
  • a temperature below 36°C
  • you feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery and shaking
  • a sore throat
  • a cough 
  • breathlessness
  • diarrhoea
  • needing to pass urine (pee) often, or discomfort when you pass urine.

It is important to follow any specific advice your cancer treatment team gives you.

Your white blood cell count will usually return to normal before your next treatment. You will have a blood test before having more treatment. If your white blood cell count is low, your doctor may delay your treatment for a short time, until your cell count increases.

You may be given a drug called G-CSF. This encourages the body to make more white blood cells. You have it as a small injection under the skin.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot.

If the number of platelets is low, you may bruise or bleed easily. You may have:

  • nosebleeds
  • bleeding gums
  • heavy periods
  • blood in your urine (pee) or stools (poo)
  • tiny red, brown or purple spots that may look like a rash – these spots can be harder to see if you have black or brown skin. 

If you have any unexplained bruising or bleeding, contact the hospital straight away on the 24-hour number. You may need a drip to give you extra platelets. This is called a platelet transfusion.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may feel:

  • very low in energy
  • breathless 
  • dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Feeling sick

The nurses will give you anti-sickness drugs regularly. This will help prevent or control sickness during your treatment in hospital. If you feel sick or are sick (vomit), tell your nurse or doctor straight away. They can change the anti-sickness treatment. Or they might change the way you have it to something that works better for you.

Sore mouth and throat

This treatment may cause a sore mouth and throat. You may also get mouth ulcers. This can make you more likely to get a mouth or throat infection. Use a soft toothbrush to clean your teeth or dentures in the morning, at night and after meals.

Contact the hospital straight away on the 24-hour number, if:

  • a sore mouth or throat affects how much you can drink or eat 
  • your mouth, tongue, throat or lips have any blisters, ulcers or white patches. 

They can give you advice, and mouthwash or medicines to help with the pain or to treat any infection. Follow their advice and make sure you:

  • drink plenty of fluids
  • avoid alcohol and tobacco
  • avoid food or drinks that irritate your mouth and throat.

Changes to your taste

Some foods may taste different or have no taste. Try different foods to find out what tastes best to you. You may also get a bitter or metallic taste in your mouth. Your doctor, nurse or pharmacist can give you advice. It might help to try:

  • sucking sugar-free sour or boiled sweets
  • eating cold foods
  • eating sharp-tasting fresh fruit.

Taste changes usually get better after treatment ends. We have more information about coping with changes to taste.

Diarrhoea

This treatment may cause severe diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.

Your hospital team may give you anti-diarrhoea drugs to take.

If you have diarrhoea or a mild increase in stoma activity:

  • follow any advice from your cancer team about taking anti-diarrhoea drugs 
  • drink at least 2 litres (3½ pints) of fluids each day
  • avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods. 

Tell your doctor or nurse straight away if:

  • you have diarrhoea at night
  • you have diarrhoea more than 4 times in a day
  • you have a moderate or severe increase in stoma activity
  • the anti-diarrhoea drugs do not work within 24 hours.

You may need to have extra fluids through a drip.

Tummy pain

You may get pain in your tummy (abdomen), or have indigestion. Your doctor, nurse or pharmacist can give you advice or treatment to help. Contact the hospital straight away on the 24-hour number if your symptoms do not go away, or get worse.

Constipation

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

  • Drink at least 2 litres (3½ pints) of fluids each day.
  • Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
  • Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

Effects on the kidneys

Methotrexate can affect how your kidneys work. This is usually only when you have it in high doses. Your doctor can tell you more about this. Your doctor will ask you about any other medicines or supplements you take, as some can affect how your kidneys clear methotrexate from your body.

You will have blood and urine tests before and during treatment to check how well your kidneys are working. They will also monitor how much urine (pee) you pass during your treatment.

Before and after each treatment, your nurses will give you extra fluids through a drip. This is to protect your kidneys. It is also important to drink at least 2 litres (3½ pints) of non-alcoholic fluid each day during treatment.

Tell your nurse or doctor if you are:

  • not able to drink as much as you have been asked to – for example, if you feel sick
  • being sick or have diarrhoea
  • passing urine (peeing) less than usual.

Feeling tired (fatigue)

This treatment can make you feel very tired and you will need a lot of rest. You may get tired easily for some months after treatment ends. Gentle exercise, like short walks, can help you feel less tired. The tiredness will slowly get better. 

If you feel sleepy, do not drive or use machinery.

Loss of appetite

This treatment can affect your appetite. Don’t worry if you do not eat much for 1 or 2 days. But if your appetite does not come back after a few days, or if you are losing weight, tell your doctor, nurse or pharmacist. They can give you advice. They may give you food or drink supplements. Or they may suggest changes to your diet or eating habits to help.

Pain

You may get pain in your muscles, joints or where your tumour is. If this happens, tell your doctor so they can give you painkillers. Tell them if the pain does not get better.

If you have painkillers you would like to use at home, check with your doctor, nurse or pharmacist whether they are suitable for you.

Hand-foot (palmar-plantar) syndrome

This treatment can affect the palms of your hands and the soles of your feet. This is called palmar-plantar or hand-foot syndrome. 

If you have white skin these areas may become red. If you have black or brown skin, these areas might get darker. 

The skin on the palms of your hands and the soles of your feet may:

  • be sore
  • be painful, tingle, or swell
  • peel, crack or blister. 

If you have any of these symptoms, contact the hospital straight away on the 24-hour number. They can give you advice. This is especially important if you have any broken skin or if walking is difficult. They can prescribe creams and painkillers to help.

You can care for your hands and feet by: 

  • keeping your hands and feet cool by washing in cool water
  • gently moisturising your hands and feet regularly
  • wearing gloves to protect your hands and nails when working in the house or garden
  • wearing loose cotton socks and avoiding tight-fitting shoes and gloves.

Skin changes

Chemotherapy can affect your skin. If your skin feels dry, try using soap-free cleansers and unperfumed moisturising cream every day.

This treatment can also:

  • cause a rash, which may be itchy 
  • make your skin darker in some areas 
  • make any area treated with radiotherapy become red or sore. If you have white skin the area will become red and if you have black or brown skin the area might become darker. 
  • make you more sensitive to the sun. 

Your skin may burn more easily during treatment and for several months after. Use a sun cream of at least SPF 30. SPF stands for sun protection factor. Cover up with clothing and wear a hat. 

Always tell your doctor, nurse or pharmacist about any skin changes. They can give you advice or prescribe creams or medicines to help. Changes to your skin are usually temporary and improve when treatment ends.

Serious skin changes

Rarely, this treatment can cause a serious skin reaction that needs to be treated immediately in hospital. Contact the hospital straight away on the 24-hour number if you have any of these symptoms:

  • a skin rash that is spreading 
  • blistering or peeling skin
  • flu-like symptoms, such as a high temperature and joint pain
  • sores on your lips or in your mouth.

Hair loss

Your hair will get thinner. Or you may lose all the hair from your head. You may also lose your eyelashes and eyebrows, as well as other body hair. Hair loss usually starts after your first or second treatment.

If you want to cover up hair loss, there are different ways you can do this. Your nurse will give you information about coping with hair loss

Remember to protect your skin from the sun. Use suncream with a sun protection factor (SPF) of at least 30 on your scalp. Or cover up with a hat or scarf.

Hair loss is almost always temporary. Your hair will usually grow back after treatment ends.

Effects on the liver

This treatment may affect how your liver works. This is usually mild. Liver problems may cause the skin or the whites of the eyes to become yellow.

You will have blood tests to check how well your liver is working. Your doctor or nurse may suggest you avoid alcohol and some medicines.

Raised blood sugar levels

This treatment can raise your blood sugar levels and increase the risk of diabetes. 

Signs of raised blood sugar include:

  • feeling thirsty
  • needing to pass urine (pee) more often than usual
  • feeling more tired than usual. 

Tell your doctor or nurse if you have these symptoms. They can do tests to check your blood sugar level and give you advice.

If you already have diabetes, your blood sugars may be higher than usual. You may need to check them more often, or make changes to your diabetic treatment. Your diabetic doctor or nurse will talk to you about how to manage this.

Eye problems

Your eyes may become watery and feel sore. Your doctor can prescribe eye drops to help with this. If your eyes get red and inflamed, tell your doctor. This is called conjunctivitis. You may need antibiotic eye drops.

Always tell your doctor or nurse if you have pain or notice any change in your vision.

Cytarabine and methotrexate may also:

  • make your eyes more sensitive to light
  • cause blurry vision
  • cause eye pain.

You will be given steroid eye drops to help prevent this.

You should not drive or operate machinery if you have blurry vision.

Less common side effects

Effects on the nervous system

This treatment can affect the nervous system. Tell your doctor or nurse straight away if you have, or someone with you notices you have, any of these symptoms:

  • headaches or dizziness
  • changes in eyesight
  • numbness or tingling in your arms or legs
  • problems with moving or speaking
  • loss of balance or co-ordination
  • loss of memory or concentration
  • feeling drowsy or confused
  • feeling anxious or restless or low in mood
  • fits (seizures).

You should not drive or operate machinery if you have these symptoms.

Effects on the lungs

This treatment can cause inflammation of the lungs. This is called pneumonitis. Contact the hospital straight away on the 24-hour number if you notice any of these changes during treatment or after it ends:

  • breathlessness
  • a cough that does not go away
  • wheezing
  • a fever, with a temperature over 37.5°C.

You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs. You may need steroids or other treatments.

Effects on the heart

This treatment can affect how the heart works. You may have tests to check how well your heart is working. These may be done before, during and after treatment.

If the treatment is causing heart problems, your doctor may change the type of treatment you are having.

Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • breathlessness
  • dizziness
  • changes to your heartbeat (palpitations)
  • swollen feet and ankles.

Other conditions can cause these symptoms, but it is important to get them checked by a doctor.

Always call 999 if you have:

  • chest pain, pressure, heaviness, tightness or squeezing across the chest
  • difficulty breathing.

Hearing changes

This treatment may cause hearing changes, including hearing loss. You may have ringing in the ears. This is called tinnitus. You may also become unable to hear some high-pitched sounds. Hearing changes may get better after this treatment ends. But this does not always happen. If you notice any changes in your hearing, tell your doctor, nurse or pharmacist.

Tumour lysis syndrome (TLS)

Some people are at risk of developing a condition called tumour lysis syndrome (TLS). The risk is highest at the beginning of treatment. TLS happens when treatment makes large numbers of cancer cells die and break down quickly. This releases lots of waste products into the blood and can affect the kidneys and heart.

TLS can be prevented or treated. You will have regular blood tests to check for TLS. You may have:

  • extra fluids through a drip
  • medicines such as allopurinol tablets or rasburicase through a drip.

Drinking at least 2 litres (3½ pints) of fluid a day will also help.

Second cancer

This treatment can increase the risk of developing a second cancer years later. This is rare. The benefits of treatment usually far outweigh this risk. Your doctor, nurse or pharmacist can talk to you about this.

Other important information

Blood clot risk

Cancer and some cancer treatments can increase the risk of a blood clot. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • throbbing pain or swelling in a leg or arm
  • reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
  • suddenly feeling breathless or coughing.

Always call 999 if you have:

  • chest pain
  • difficulty breathing.

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

Hepatitis B reactivation

If you have ever had a liver infection called hepatitis B, MATRix can make it active again. Your doctor or nurse will talk to you about this and test you for hepatitis B. If you have active hepatitis B, you doctor will explain more about this.

Other medicines

Some medicines can affect how this treatment works or be harmful while you are having it. Always tell your cancer doctor, nurse or pharmacist about any drugs you are taking or planning to take, such as: 

Vaccinations

Doctors usually recommend that people with cancer have vaccinations for flu and for coronavirus (covid). These help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

If your immune system is weak, you should not have live vaccinations. Live vaccines can make you unwell because they contain a very weak version of the illness they will protect you against. Live vaccines include Zostavax®, which is a shingles vaccine, and the yellow fever vaccine.

It is important to ask your doctor, nurse or pharmacist for advice about having vaccinations. They can explain what vaccines are right for you and when it is best to have them.

Contraception

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

  • what types of contraception to use 
  • how long after treatment you should continue to use contraception. 

Breastfeeding

You are advised not to breastfeed while having this treatment, or for some time after treatment ends. This is because the drugs could be passed to the baby through breast milk. 

Your doctor, nurse or pharmacist can give you more information.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Sex

It is possible that small amounts of chemotherapy may be passed on through vaginal fluids or semen. If you have sex in the first few days after treatment, your cancer team will usually advise using condoms or a dental dam to protect your partner.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.

About our information

This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer.

Date reviewed

Reviewed: 01 March 2024
|
Next review: 01 March 2026
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

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