What is HCX?

HCX is used to treat stomach (gastric) cancer and cancer where the gullet joins the stomach (gastro-oesophageal cancer) It is used if the cancer is human epidermal growth factor receptor 2 (HER2) positive.

HCX is named after the initials of the drugs used in the treatment:

Cisplatin and capecitabine are chemotherapy drugs. Trastuzumab is a targeted therapy drug. It is best to read this information with our general information about chemotherapy, targeted therapy and the type of cancer you have.

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

What is HER2 positive cancer?

HER2 is a protein. Some stomach cancers have too much of this protein on the surface of their cells. These are called HER2 positive cancers. The extra HER2 protein helps the cancer cells to divide and grow.

Trastuzumab blocks the HER2 protein. This helps stop the cancer cells from dividing and growing.

The only way to check if a cancer is HER2 positive is to test the cancer cells. Tests can be done on cell samples taken during:

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.

DPD testing before treatment

Before starting this treatment, you should have a blood test to check for gene changes that affect how your body produces DPD. DPD is an enzyme that helps the body break down capecitabine. 

If you have low DPD levels or no DPD (DPD deficiency), you have more risk of serious or life-threatening side effects from capecitabine. To reduce your risk, your doctor may give you:

  • a lower dose of capecitabine to start with
  • a different type of chemotherapy.

Having low DPD levels does not usually cause any symptoms. Without a test, you will not know whether your DPD levels are low. Testing finds most people who are affected, but not all. Your doctor, nurse or pharmacist can give you more information about your risk of DPD deficiency, before you start treatment.

How HCX is given

You will be given HCX in the chemotherapy day unit or during a stay in hospital. A chemotherapy nurse will give it to you.

During treatment you usually see a cancer doctor, a chemotherapy nurse or a specialist nurse, and a specialist pharmacist. This is who we mean when we mention doctor, nurse or pharmacist in this information.

Before or on the day of treatment, a nurse or person trained to take blood (phlebotomist) will take a blood sample from you. This is to check that your blood cells are at a safe level to have chemotherapy. 

You will see a doctor or nurse before you have chemotherapy. They will talk to you about your blood results and ask you how you have been feeling. If your blood results are okay, the pharmacist will prepare your chemotherapy. Your nurse will tell you when your treatment is likely to be ready. 

Your nurse usually gives you anti-sickness (anti-emetic) drugs before the chemotherapy. Trastuzumab and cisplatin are given through: 

  • a cannula – a short, thin tube the nurse puts into a vein in your arm or hand
  • a central line – a fine tube that goes under the skin of your chest and into a vein close by
  • a PICC line – a fine tube that is put into a vein in your arm and goes up into a vein in your chest
  • an implantable port (portacath) – a disc that is put under the skin on your chest or arm and goes into a vein in your chest.

Your nurse will give you trastuzumab as a drip (infusion) that is attached to your cannula or line. They usually put the drip through a pump. This will give you the treatment over a set time. The first dose is usually given slowly over 90 minutes. You need to stay in hospital for a few hours afterwards so the nurses can check you for any reaction. Your next trastuzumab treatments are usually given over about 30 minutes. 

Your nurse also give you cisplatin as a drip (infusion). It may be given before or after the trastuzumab drip. 

You will be given extra fluids given through the drip before and after the cisplatin. You may also have a drug called mannitol. This is because cisplatin can affect the kidneys. The fluids and mannitol can help prevent kidney damage. Your nurse will explain how long it will take to have the extra fluids. They will also give you advice about how much fluid to drink for the next 24 hours.

You take capecitabine as tablets.

Your course of chemotherapy

You usually have a course of several cycles of treatment over a few months. Your nurse or doctor will talk to you about how the treatment will be given. They may give you a copy of a treatment plan to take home with you.

Each cycle takes 21 days (3 weeks). You will have trastuzumab and cisplatin as separate drips at the start of each cycle. The nurse or pharmacist will then give you capecitabine tablets to take home. You may be told to take the capecitabine tablets:

  • every day for 14 days, followed by a 7-day rest period with no treatment.
  • or every day of the cycle of treatment.

Your nurse or pharmacist may also give you anti-sickness drugs and other medicines to take home. They may also give you anti-diarrhoea tablets if you need them. Take all capsules and tablets exactly as they have been explained to you.

Taking capecitabine tablets

You will have capecitabine as tablets. Before you leave hospital, the nurse or pharmacist will give you capecitabine tablets to take at home. Always take your tablets exactly as explained. This is important to make sure they work as well as possible for you.

You may be given tablets of different strengths. The dose of chemotherapy that you are prescribed may change from one cycle to the next. This may be because of any side effects you have, or changes to your weight. It is very important that you know how many tablets to take each time you start a new cycle. You take capecitabine tablets twice a day.

Capecitabine should be swallowed whole with a glass of water within half an hour of eating a meal. Take them in the morning after breakfast and then after your evening meal.

Tell your doctor if you find it difficult to swallow the tablets. They may suggest that you dissolve the capecitabine tablets in water. In this case, dissolve the tablets in a 200ml glass of warm water. Stir the water with a spoon until the tablets are completely dissolved and then drink it immediately. The glass and spoon should be washed and kept separate from your other crockery and cooking utensils. Do not crush or cut the capecitabine tablets.

If you forget to take a tablet, do not take a double dose. Take the next dose when it is due and let your doctor or nurse know.

Other things to remember about your tablets:

  • Wash your hands after taking your tablets.
  • Other people should avoid direct contact with the chemotherapy drugs.
  • Keep them in the original package and at room temperature, away from heat and direct sunlight.
  • Keep them safe and out of sight and reach of children.
  • If you are sick just after taking the tablets, contact the hospital. Do not take another dose.
  • If your treatment is stopped return any unused tablets to the pharmacist.

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.

If your body does not produce enough of an enzyme called DPD, you may have a higher risk of severe or life-threatening side effects.

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 may have side effects while they are being given the chemotherapy or shortly after they have it:

Allergic reaction

Some people have an allergic reaction while having this treatment. 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 treatment. 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.

The drug leaks outside the vein

The drug may leak outside the vein. If this happens it can damage the tissue around the vein. This is called extravasation. Extravasation is not common but if it happens it is important that it is dealt with quickly. Tell your nurse straight away if you have any stinging, pain, redness or swelling around the vein. 

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. It is 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.

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.

Diarrhoea

Capecitabine may cause diarrhoea. Sometimes it is severe. Diarrhoea means passing more stools (poo) than is normal for you, or having watery or loose stools. If you have a stoma, it will be more active than usual. Your doctor, nurse or pharmacist may give you anti-diarrhoea drugs to take at home.

If you have diarrhoea or an increase in stoma activity, follow their advice on:

  • taking the anti-diarrhoea drugs 
  • how much and what type of fluids to drink 
  • any changes to your diet that might help. 

After this, contact the hospital on the 24-hour number straight away if:

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

They will tell you to stop taking capecitabine. When the diarrhoea is better, they will tell you whether you can start taking it again. Sometimes they reduce the dose.

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. 

Feeling sick

Your doctor, nurse or pharmacist will prescribe anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as they tell you to, even if you do not feel sick. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluid often and eat small amounts regularly. It is important to drink enough fluids. If you continue to feel sick, or if you are sick (vomit) 1 to 2 times in 24 hours, contact the hospital on the 24-hour number as soon as possible. They will give you advice. They may change your anti-sickness treatment. Let them know if you still feel sick.

Feeling tired

Feeling tired is a common side effect of this treatment. It is often worse towards the end of treatment and for some weeks after it ends. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can help you feel less tired. 

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

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.

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.

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.

Eye problems

Your eyes may become watery. Sometimes they may feel sore, red and itchy (conjunctivitis). Your doctor can give you eye drops to help with this. Your pharmacist will tell you how to use your eye drops. It is important to follow their advice.

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

This treatment may cause inflammation in the skin. This is usually mild, but can if it is not treated it can become serious. You may need creams, steroids or other medicines to treat skin problems. If you notice skin changes during treatment, or after treatment ends, contact the hospital on the 24-hour number as soon as possible. Skin changes can include: 

  • a rash or bumps on the skin
  • dry or itchy skin
  • patches of white or paler skin.

To protect your skin from the sun, use suncream with of at least SPF 30. SPF stands for sun protection factor. Cover up with clothing and a hat. 

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

  • a rash that is spreading
  • blistering or peeling skin
  • flu-like symptoms, such as a high temperature and joint pain. 

These symptoms can be a sign of a serious skin reaction that needs to be treated immediately in hospital.

Headaches

This treatment may cause headaches. If you have headaches, tell your doctor, nurse or pharmacist. They can give you advice about painkillers that may help. Tell them if the headache does not get better, or gets worse.

Feeling anxious or having difficulty sleeping

This treatment can affect your mood and may cause feelings of anxiety. It may also cause difficulty sleeping. Talk to your doctor or nurse for advice about managing these side effects.

Feeling dizzy

This treatment can cause dizziness. Tell your doctor or nurse if this is a problem.

Numb or tingling hands or feet (peripheral neuropathy)

This treatment may affect the nerves in your fingers and toes. This can cause numbness, tingling or pain in your hands or feet. This is called peripheral neuropathy. You might find it hard to do fiddly tasks such as fastening buttons or tying shoelaces.

If you have these symptoms, always tell your doctor, nurse or pharmacist. They sometimes need to change the drug or the dose of the drug. The symptoms usually improve slowly after treatment ends. But for some people they continue and are a long-term side effect of treatment.

Muscle or joint pain

You may get pain in your muscles or joints for a few days after treatment. If this happens, tell your doctor, nurse or pharmacist. They can give you painkillers and advice. They can also tell you if any of the painkillers you usually take are suitable. 

Tell them if the pain does not get better. Having warm baths and resting regularly may help. 

Tumour lysis syndrome (TLS)

Some people are at risk of developing a condition called tumour lysis syndrome (TLS) during this treatment. When treatment makes large numbers of cancer cells die and break down quickly, they release lots of waste products into the blood. This can affect how well the kidneys work. It may also cause problems with the heart rhythm.

TLS can be prevented. You will have regular blood tests to check for TLS. If you are at risk of TLS, you may have:

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

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

Effects on the heart

Capecitabine 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. 

You may develop heart problems even if these test results are normal. Very rarely, capecitabine causes heart failure or a heart attack. The risk of this happening is very low. It happens to less than 1 in 100 (1%) of people who take capecitabine. But it is important that you know about it. 

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
  • swollen feet and ankles.

If you have any of these symptoms, stop taking the capecitabine. Do not start taking it again until your doctor, nurse or pharmacist tells you to. 

Always call 999 if you have:

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

Effects on the kidneys

Cisplatin can affect how the kidneys work. You will have blood tests before and during treatment to check how well your kidneys are working.

Before and after each treatment, your nurse will give you extra fluids through a drip. This is to protect your kidneys. 

Drinking fluids also helps protect your kidneys. The advice is usually to try to drink at least 2 litres (3½ pints) of fluid each day. But follow any advice from your doctor, nurse or pharmacist about how much is right for you.

Contact the hospital on the 24-hour number if you are: 

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

Effects on the lungs

This treatment can cause changes to the lungs. Tell your doctor, nurse or pharmacist if you develop: 

  • a cough that does not go away
  • wheezing
  • breathlessness.

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

Abdominal (tummy) pain or indigestion

You may have tummy pain or indigestion. Tell your doctor or nurse if this happens. They can prescribe drugs to help.

Less common side effects

Hair loss

Your hair may get thinner. But you are unlikely to lose all the hair from your head. Hair loss usually starts after your first or second treatment. It is almost always temporary, and your hair will usually grow back after treatment ends. 

Your nurse can talk to you about ways to cope with hair loss.

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.

Other 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.

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 during this 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

  • Reviewers

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

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 September 2022
|
Next review: 01 March 2025
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.