Chemotherapy for large bowel cancer

Chemotherapy is the use of special anti-cancer (cytotoxic) drugs to destroy cancer cells.

Early-stage bowel cancer

In the treatment of cancer of the colon and rectum, chemotherapy is mainly used after surgery. The aim is to reduce the risk of the cancer coming back (this is known as adjuvant treatment).

Chemotherapy is occasionally given before surgery to treat rectal cancers and this is known as neo-adjuvant chemotherapy. Radiotherapy may be given at the same time as chemotherapy and this is called neo-adjuvant or pre-operative chemoradiotherapy.

Neo-adjuvant chemotherapy

Neo-adjuvant chemotherapy is mainly given to treat cancers affecting the rectum. The aim of the treatment is to reduce the size of the tumour to make it easier to remove during surgery, which may make it possible to avoid having a permanent colostomy.

Pros and cons of chemotherapy for early-stage cancer

If the chance of the cancer coming back is low, the chemotherapy may only slightly reduce the chance of the cancer returning. On the other hand, if the risk of the cancer coming back is high, the chemotherapy can greatly reduce the chance of the cancer returning.

It is important to discuss with your doctor the possible risks and benefits  of chemotherapy in your particular situation, so that you can balance the possible benefits against the side effects and decide whether or not to have treatment.

Adjuvant chemotherapy for bowel cancer is usually with a chemotherapy drug called 5-fluorouracil (5FU). 5FU is usually given in combination with a vitamin called folinic acid, which makes it more effective. There are several different ways of giving this chemotherapy. Your specialist will explain your particular course of treatment to you.

Research trials are also testing other types of adjuvant therapy, including several other chemotherapy drugs which may be given as injections or tablets. You may be asked to consider taking part in a research trial to evaluate one of these treatments.

Chemotherapy for advanced (secondary) cancer of the large bowel

Chemotherapy may also be given when the cancer has spread to another part of the body (secondary or advanced cancer). Many people have no further problems after their original treatment for cancer of the large bowel, but unfortunately in some people the cancer comes back or spreads to other parts of the body. This is called secondary (or metastatic) cancer of the large bowel.

Sometimes, when the cancer is first diagnosed, it may already have spread beyond the bowel. The most common parts of the body for colon and rectal cancer to spread to are the liver and the lungs.

Although secondary cancer of the large bowel cannot usually be cured, treatment with chemotherapy may be recommended by your doctor. Often the aim of the chemotherapy is to shrink the tumours and improve symptoms. This can sometimes help to prolong life. Chemotherapy may be given to shrink tumours before they are removed from the liver or, more rarely, the lungs.

Pros and cons of chemotherapy for advanced bowel cancer

There are various pros and cons of chemotherapy in these situations and it is important to discuss these with your cancer specialist.

It is not possible to predict whether the chemotherapy will work for a particular person, but if a person is fairly fit the treatment is more likely to be effective. It is also less likely to have side effects, than in someone who is unwell when they start the treatment.

If you do not want to have chemotherapy treatment, you can be given medicines to help control any symptoms that the cancer causes. This is known as supportive, or palliative care.

Your doctor will consider a number of things before asking you to make a decision about particular treatments. This will include where the secondary cancer is, your general health and any chemotherapy treatment you have had in the past.

The most commonly used chemotherapy drugs for advanced bowel cancer are:

• 5-fluorouracil (5FU), which is usually given with the vitamin folinic acid
• irinotecan (Campto®)
• oxaliplatin (Eloxatin®)
• tegafur with uracil (Uftoral®) tablets
• capecitabine (Xeloda®).

Several research trials are being carried out to test new drugs for advanced colorectal cancer and to help find the best way of using the current drugs  (those mentioned above). You may be asked to take part in a research trial using new chemotherapy drugs or new types of treatments.

If the cancer starts to grow again, during or after the chemotherapy, you may be given a different type of chemotherapy (this is known as second-line treatment). Sometimes third-line chemotherapy may also be given.

CancerBACUP’s sections on controlling cancer pain and controlling the symptoms of cancer, explain ways in which pain and symptoms can be controlled. They also give information on the type of support that is available from health professionals and other sources.

How chemotherapy is given

Some chemotherapy drugs are given as capsules or tablets. These are swallowed with water. The capsules are mainly used to treat people with advanced colorectal cancer.

Most people with colorectal cancer will have their chemotherapy drugs given by injection into a vein (intravenously). The drugs may be given through a thin tube inserted into a vein in the crook of your arm (known as a PICC line), or through a plastic line called a central line in your chest.

Sometimes chemotherapy can be given to you through a small portable pump, the size of a Walkman. The pump is attached to your central or PICC line. A controlled amount of the drug can be given into the bloodstream over a period of time. This means that you can go home with the pump and so spend less time in hospital. Some people whose cancer has spread to the liver may be given chemotherapy into a vein which goes directly into the liver.

Chemotherapy into a vein in the arm or through a central or PICC line can be given as a session of treatment. A session may last from a few hours to several days. If you have treatment for a few hours, this may be repeated each week for several months. This chemotherapy is usually given as an outpatient.

If your treatment lasts a few days you will usually have a rest period of a few weeks before the next session, which allows your body to recover from the side effects of the treatment. The chemotherapy session and the rest period make up a cycle of treatment. You may need to stay in hospital for your treatment. Chemotherapy can also often be given to you as an outpatient. Your specialist will discuss this with you.

The number of cycles you have will depend on the stage of cancer you have and how well it is responding to the drugs.

Side effects

Chemotherapy can sometimes cause unpleasant side effects, but if your cancer is causing symptoms it can also make you feel better by relieving them. Most people have some side effects, but these can usually be well controlled with medicine. Common problems are described here, along with some of the ways they can be reduced.

Reduced resistance to infection

While the drugs are acting on the cancer cells in your body, they may also temporarily reduce the number of normal white blood cells. When these cells are reduced you are more likely to get an infection. It is important to avoid crowded places, where you may come into contact with infection, and to avoid anyone who already has an infection, such as a cold or flu while your level of white blood cells is low.

It is important to contact your doctor or the hospital straightaway if you have any signs of infection, such as a high temperature (above 38ºC or 100.5°F), or if you suddenly feel unwell (even with a normal temperature). During chemotherapy your blood will be tested regularly and, if necessary, you will be given antibiotics to treat any infection.

Tiredness

You are likely to find that you become very tired and have to take things much more slowly. Just do as much as you feel like and try not to overdo it. CancerBACUP has a section on coping with fatigue, which you may find helpful.

Feeling sick

Some of the drugs may make you feel sick (nauseated) and possibly be sick (vomit). There are very effective anti-sickness drugs (anti-emetics) to prevent or greatly reduce nausea and vomiting. Your doctor will prescribe these for you. Let your doctor or nurse know if your anti-sickness drugs are not helping you, as there are several different types that can be used.

Diarrhoea

Some of the chemotherapy drugs used to treat bowel cancer can cause diarrhoea. This often starts several days after the treatment. If you are taking chemotherapy tablets or capsules at home, it is important that you let your doctor or nurse know that you have diarrhoea as your treatment may need to be stopped.

If you have diarrhoea your doctor can give you medicine to reduce this and slow down the bowel. You may also be able to help control it by eating a low fibre diet. CancerBACUP’s section on diet and the cancer patient can give you advice on this.

If you have had a colostomy or ileostomy, it may be more difficult to cope with diarrhoea caused by the chemotherapy, and your stoma nurse or cancer specialist can give you advice and support. Some people find that they need to make sure they are close to a toilet during the course of their treatment and for a while afterwards. This can be very frustrating, but usually gradually improves a few weeks after the treatment has ended.

If the diarrhoea continues after this time it is important to talk to your cancer specialist or stoma nurse, so that they can help you find ways of overcoming the diarrhoea.

Sore mouth

You may find that you get a sore mouth and mouth ulcers while having chemotherapy. Keeping your mouth clean with regular mouthwashes is important and your nurse will show you how to use these properly. If a sore mouth makes eating difficult, you can try replacing meals with nutritious drinks.

Hair loss

Ask your doctor if the drugs you are taking are likely to make your hair fall out. Most drugs used to treat bowel cancer do not, but some may make your hair thin. If your hair does fall out, it will start to grow back again once your treatment is over.

Soreness of hands and feet

Soreness and redness of the palms of the hand and soles of the feet can occur when 5FU or capecitabine are given over a long period of time or when they are  given continuously through a pump. It is known as palmar-plantar syndrome. A vitamin can be prescribed to help to reduce this side effect and simple moisturising creams can often help to relieve the symptoms.

Numbness or tingling

Oxaliplatin can affect the nerve endings and cause peripheral neuropathy. This can cause numbness or tingling in the hands, feet, neck or throat.

Sometimes these symptoms can be triggered by anything cold, such as cold drinks or weather. The numbness or tingling may not happen with the first treatment. If it occurs, it should begin to improve once the treatment has finished.

Although they may be hard to bear at the time, these side effects gradually disappear once your treatment is over. Tell your doctor if you have side effects, as many can be eased with medicine.