Chemotherapy

Chemotherapy is a treatment that destroys cancer cells using anti-cancer drugs. It works by affecting their ability to divide and grow.

Different chemotherapy drugs work in different ways and affect cancer cells at different times in their growth. This is why a combination of drugs is often used.

Find out about the drugs used for chemotherapy.

Chemotherapy also affects other cells throughout the body, which causes side effects.

Primary breast cancer

Before surgery

You may have chemotherapy before surgery to slow the growth of fast-growing breast cancer. Or you may have it to shrink a larger breast cancer before surgery. This may mean breast-conserving surgery is an option, rather than a mastectomy.

Chemotherapy given before surgery is called primary or neoadjuvant chemotherapy.

You may be more likely to have chemotherapy before surgery if you have inflammatory or triple negative breast cancer, or if your breast cancer is HER2 positive.

After surgery

You may have chemotherapy after surgery for primary breast cancer to reduce the risk of the cancer returning or spreading. This is called adjuvant chemotherapy.

You may be given chemotherapy in combination with other treatments.

Secondary breast cancer

Chemotherapy can also be used to treat secondary breast cancer. Secondary breast cancer is breast cancer that has spread to another part of the body, such as the bones, lungs, liver or brain.

Secondary breast cancer, also called metastatic breast cancer, can be treated but cannot be cured.

Chemotherapy aims to slow down and control the growth of secondary breast cancer and relieve symptoms.

Different chemotherapy drugs are used to treat secondary breast cancer. You may be given them on their own or in combination with other treatments.

Find out more about the benefits of chemotherapy for treating primary breast cancer.

The benefits of chemotherapy for treating secondary breast cancer will depend on where the secondary breast cancer is in the body and any chemotherapy you’ve had before.

Before starting your treatment, a member of your treatment team will discuss how and when you’ll have chemotherapy and how side effects can be managed.

You’ll have blood tests and your height and weight will be measured.

You may also have tests to check your heart function, such as:

• An ECG (electrocardiogram)
• An echocardiogram (echo) 
• A MUGA (multiple-gated acquisition) scan 

You should be given a 24-hour contact number or told who to contact if you feel unwell at any time during your treatment, including overnight or at the weekends.

You’ll be asked to sign a consent form before you start chemotherapy. The benefits and risks of the treatment should be fully explained to you before you sign it.

You’ll usually be given anti-sickness (also called anti-emetic) drugs before each chemotherapy treatment. The drugs you’re given will depend on the type of chemotherapy you’re having, but will often include a steroid drug called dexamethasone as well as the anti-sickness medication.

Chemotherapy can be given in several ways. For breast cancer, the drugs are most commonly given:

• Into a vein (intravenously)
• By mouth as tablets or capsules (orally)

You may have 1 drug or a combination of 2 or 3 drugs. The exact type and dose of chemotherapy will be tailored to suit you. The drugs used, the dose, how often you have them and the number of cycles may be called your chemotherapy “regime” or “regimen”.

How long you have chemotherapy will depend on your individual situation. Your treatment team will discuss this with you.

Chemotherapy cycles

You’ll normally have chemotherapy as a series of treatments with a break between each treatment. This allows your body time to recover from any short-term side effects. The treatment and period of time before the next one starts is called a cycle.

Cycles usually last between 1 and 6 weeks.

You’ll have a blood test shortly before, and sometimes in between, each cycle of treatment.

If the number of blood cells in your body is too low, your treatment may need to be delayed.

Intravenous chemotherapy

If you’re having intravenous chemotherapy, you’ll normally have your treatment at hospital as an outpatient or day case. This means you’ll be able to go home the same day.

You may be at the hospital for a short time only. However, because of tests, waiting times and how long it takes to prepare and give the chemotherapy drugs, you may be there for most of the day.

You might find it helpful to take things to pass the time, as well as snacks and drinks. You may be able to take someone with you to keep you company. Talk to your chemotherapy nurse to find out if this is possible.

In some areas of the country, chemotherapy may be given in a mobile treatment centre or in your home. Find out more about chemotherapy safety at home on the Cancer Research UK website.  

With some types of chemotherapy, you may need to stay in hospital overnight for your first treatment.

Oral chemotherapy

You usually take oral chemotherapy at home.

Like any treatment, chemotherapy can cause side effects. Everyone reacts differently to drugs and some people have more side effects than others.

Find out more about the side effects of chemotherapy.

Complementary therapies

Many people find complementary therapies help them cope with the side effects of chemotherapy, even though there may not be the evidence to support this.

There are many different types of complementary therapies including acupuncture, aromatherapy, reflexology, herbal remedies and hypnotherapy.

Check with your treatment team or GP before having any complementary therapies. Your GP or treatment team may advise avoiding some therapies (particularly herbal remedies) if there’s a chance they could affect how your breast cancer treatment works.

Some therapies are available in NHS hospitals, so ask your treatment team what’s available to you.

Let any therapist you see know about your breast cancer and treatment.

Diet and supplements

You may be able to eat normally throughout chemotherapy. Or your eating habits may change because of the side effects of your treatment. Some people lose weight during treatment, while others gain weight.

There are many conflicting theories about diet and breast cancer, which can be confusing. It’s important to eat and drink what you feel able to, maintaining a healthy, well-balanced diet wherever possible.

Learn more about healthy eating during chemotherapy and after treatment.

Can I take supplements?

Tell your treatment team about any supplements you take or would like to start taking. These include:

• Vitamin and mineral supplements
• Herbal remedies
• Any treatments bought over the counter or online

The evidence is conflicting about how safe it is to take vitamin supplements, particularly high-dose antioxidants (including vitamins A, C and E, Co-enzyme Q10 and selenium), during chemotherapy. Some studies suggest they might make the chemotherapy less effective, while others say they help reduce chemotherapy side effects.

Because the safety evidence is not clear, many specialists recommend not taking high-dose antioxidant supplements during chemotherapy.

Sex, contraception and pregnancy

You can still have sex during treatment. It’s thought chemotherapy drugs cannot pass into vaginal fluids or semen, but this cannot be completely ruled out.

Most treatment teams will advise using barrier methods of contraception, such as condoms, during treatment and for a few days after chemotherapy is given.

You’re advised not to become pregnant while having treatment because chemotherapy can harm a developing baby. If you have not been through the menopause, talk to your treatment team about the most suitable method of contraception for you. It’s still possible to become pregnant even if your periods are irregular or have stopped.

It’s normal for chemotherapy to affect how you feel about sex and intimacy. You may not feel like being intimate when you’re having treatment, or you may find intimacy helps you feel more normal. Everyone responds differently.

Find out more about how breast cancer and its treatment can affect sex and intimacy and read our tips on how to manage these changes.

Vaccinations and travel

If you’re planning a holiday or need to travel overseas, check with your treatment team first.

You should not have any live vaccines while you’re having treatment.

For more information about vaccines, including COVID-19 and flu vaccines, see our information on vaccines and breast cancer. 

It’s completely natural to feel anxious about having chemotherapy and the side effects it might cause. But most side effects can be controlled.

You should be told what side effects to report, as well as details of who to contact, day or night, if you have any concerns or feel unwell.

Your chemotherapy team and breast care nurse can help with any questions you have.

On our online forum, you can find people going through treatment at the same time as you on the chemotherapy monthly threads.

You can also contact our free helpline – see below.