Chemotherapy

How chemotherapy works

Cancer cells grow by dividing in a disorderly and uncontrolled way. Chemotherapy interferes with their ability to divide and grow.

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

How chemotherapy is used

You’ll usually be offered chemotherapy if cancer cells have been found in the lymph nodes under the arm. Even if there is no spread to the nodes, chemotherapy may be offered based on other factors, including your age and the size and grade of your breast cancer (how different the cells are to normal breast cells and how quickly they are growing).

Chemotherapy is commonly given as well as surgery and/or radiotherapy for primary invasive breast cancer, usually after surgery and before radiotherapy. This is known as adjuvant treatment (given in addition to other treatment). After your surgery, your specialist team will meet to discuss the results of your surgery and decide on any adjuvant treatments.

Some people are offered chemotherapy before surgery. This is called neo-adjuvant or primary chemotherapy. It may be used to slow the development of rapidly growing cancers or to shrink larger cancers.

Secondary, or metastatic, breast cancer is when breast cancer cells have spread from the breast to other parts of the body, such as the bones or lungs. Chemotherapy can be given to shrink or control the growth of secondary breast cancer. It can also be given to reduce some symptoms caused by the secondary breast cancer.

Benefits of chemotherapy

Research shows that the benefits of chemotherapy may be different for each person. How effective it is depends on:

• what type of breast cancer you have
• the size of the cancer
• the stage of the cancer (extent of spread)
• the grade of the cancer (potential to spread).

The benefits of chemotherapy are often clear, but if they are less obvious it can be difficult to decide whether or not to have the treatment. You’ll need to weigh up the likely benefits against the potential side effects.

Your decision may be influenced by personal priorities, your family and your work commitments. It’s important for you to discuss these issues openly with your specialist or breast care nurse, who will help and support you with your decision.

There are a number of decision-making aids using computer programmes that may help predict chemotherapy benefit. In addition, a test called Oncotype DX can sometimes help your specialist team decide if you would benefit from having chemotherapy as part of your treatment and how likely it is that your cancer will return in the future. However, Oncotype DX is not generally available through the NHS unless as part of a clinical trial, although its use is currently being reviewed by the National Institute for Health and Clinical Excellence (NICE). Some private healthcare companies may cover the cost of the test.

How long treatment may take

Chemotherapy for breast cancer is usually given as a series of treatments every two to four weeks over a period of four to six months. This can vary, depending on the type and stage of your cancer, your general health and the combination of drugs used.

The gap between courses of treatment gives your body time to recover from any short-term side effects.

You’ll normally be given your treatment as an outpatient so you will be able to go home the same day. On each treatment day, you should expect to be at the hospital for most of the day to allow for waiting time and for treatment.

Before each course of chemotherapy begins you will have a blood test to ensure your blood cell levels are within safe limits. Blood is often taken on the same day but can be taken earlier, for example the day before.

With some types of chemotherapy you may be given your first treatment as an inpatient and stay in hospital overnight.