What is chemotherapy?

Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. Cytotoxic means toxic to cells. These drugs disrupt the way cancer cells grow and divide but they also affect normal cells.

When you have chemotherapy

Chemotherapy for breast cancer can be given either before or after surgery to remove the cancer. Your cancer doctor or specialist nurse will talk to you about the benefits of chemotherapy in your situation and explain the likely side effects.

Before surgery

You may be offered chemotherapy before surgery if the cancer is large or is growing more quickly. This is called neo-adjuvant treatment. It may also be recommended if you have the following breast cancer types:

  • HER2 positive breast cancer

    Some breast cancer cells have hormone or protein receptors that affect how the cancer grows. We have separate information about breast cancer receptors in women and in men.

  • Triple negative breast cancer

    Triple negative breast cancer does not have protein receptors for either HER2 or the hormones oestrogen and progesterone. This cancer type is very rare in men.

  • Inflammatory breast cancer

    Inflammatory breast cancer is when cancer cells grow along and block the tiny channels (lymph vessels) in the skin of the breast. The breast then becomes inflamed and swollen. This cancer type is very rare in men.

Chemotherapy is given to:

  • reduce the risk of the cancer coming back
  • shrink the size of the cancer before surgery which may help to avoid having a mastectomy.

After surgery

Your cancer doctor may recommend you have chemotherapy after surgery to reduce the risk of breast cancer coming back. This is called adjuvant chemotherapy.

Your cancer doctor or specialist nurse will explain the benefits of this to you and the likely side effects.

You are usually offered chemotherapy if the cancer:

  • has spread to the lymph nodes
  • is large
  • is high-grade
  • is HER2 positive – this is more common in women than in men
  • is triple negative.

We have separate information about breast cancer and the lymphatic system for women and men.

How chemotherapy is given

You usually have chemotherapy in a chemotherapy day unit. Most drugs are given into a vein (intravenously), but some are given as tablets.

The nurse gives you the chemotherapy drugs into a vein by injection or as a drip (infusion). It can be given through:

  • a cannula – a short, thin tube put into a vein in your arm or the back of your hand
  • a central line – a long, thin tube inserted into a vein in your chest
  • a PICC line put into a vein in the arm and threaded through to a vein in the chest
  • an implantable port (portacath) that is put into a vein, with an opening (port) under the skin on your chest or arm.

Chemotherapy is often given as a few sessions of treatment. Each session takes a few hours. After the session, you have a rest period of a few weeks. The chemotherapy and the rest period is called a cycle of treatment.

The length of a cycle depends on the chemotherapy drugs you are taking. Most cycles are 1 to 3 weeks. Your cancer doctor or specialist nurse will tell you how many cycles you need.

The drugs used

Different chemotherapy drugs affect cancer cells in different ways. This is why a combination of drugs is often used. For early breast cancer, the combination often includes drugs called:

These drugs are commonly used in combination with other chemotherapy drugs, including fluorouracil and cyclophosphamide.

Some commonly used combinations include:

  • FEC – fluorouracil (5FU), epirubicin and cyclophosphamide
  • FEC-T– FEC followed by docetaxel
  • AC – doxorubicin (Adriamycin) and cyclophosphamide
  • EC – epirubicin and cyclophosphamide
  • TC – docetaxel and cyclophosphamide
  • carboplatin and paclitaxel
  • EC-T – epirubicin and cyclophosphamide followed by docetaxel
  • EC-P – epirubicin and cyclophosphamide followed by paclitaxel
  • FEC-P – fluorouracil (5FU), epirubicin and cyclophosphamide followed by paclitaxel (carboplatin may sometimes be added to this combination).

Your cancer doctor may offer you a choice of chemotherapy treatments. If so, you will be given more information to help you decide.

If you have HER2 breast cancer, you may have a targeted therapy called trastuzumab with your chemotherapy.

Sometimes the targeted therapy drug pertuzumab (Perjeta®) is given in combination with trastuzumab and chemotherapy. The combination may be used before surgery if there is a high risk of the cancer coming back.

Anthracycline chemotherapy drugs are not usually given at the same time as trastuzumab because they can both affect the heart. Your cancer doctor or specialist nurse can give you more information about this.

Side effects of chemotherapy for breast cancer

Chemotherapy drugs may cause unpleasant side effects, but these can usually be well controlled with medicines and will usually go away once treatment has finished.

Not all drugs cause the same side effects and some people may have very few. You can talk to your doctor or nurse about what to expect from the treatment that is planned for you.


About our information

  • References

    Below is a sample of the sources used in our breast cancer information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    European Society for Medical Oncology. Primary breast cancer: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. Annals of oncology 26 (supplement 5): v8–v30. 2015.

    Morrow M, et al. Chapter 79: malignant tumors of the breast. DeVita, Hellman and Rosenberg’s cancer: principals and practice of oncology (10th edition). Lippincott Williams and Wilkins. 2014.

    National Institute for Health and Care Excellence (NICE). Early and locally advanced breast cancer: diagnosis and management. July 2018.

    Scottish Intercollegiate Guidelines Network. SIGN 134. Treatment of primary breast cancer: a national clinical guideline. September 2013.

  • Reviewers

    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. It has been approved by Senior Medical Editor, Dr Rebecca Roylance, Consultant Medical Oncologist.

    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.

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