Breast cancer is the most common cancer in the UK. 1 in 8 women in the UK will develop breast cancer in their lifetime. The biggest risk factors for developing breast cancer are being female and getting older. Individual risk is affected by many different factors, such as family history, reproductive history, lifestyle, environment, and others.
In recent years there have been major advances in treating breast cancer and cure rates continue to improve.
The breast cancer diagnosis is established using different tests, such as mammogram, ultrasound of the breast and lymph nodes, breast MRI, and biopsy.
Types of breast cancer
There are two main terms that describe almost all breast cancers:
- ductal carcinoma in situ (DCIS) – this is early breast cancer
- invasive breast cancer – this has the ability to spread to other parts of the body
DCIS is called “non-invasive” because it hasn’t spread beyond the milk duct into any normal surrounding breast tissue. DCIS isn’t life-threatening, but having DCIS can increase the risk of developing an invasive breast cancer in the future. If DCIS is left untreated, the cells may become invasive.
Invasive breast cancer
Invasive means that the cancer has “invaded” or spread to the surrounding breast tissues. It has the potential to spread from the breast to the lymph glands in the armpit and other parts of the body.
A more detailed description of different types of breast cancer can be found on the Breast Cancer Care website.
Treatment of breast cancer
Treatment may involve surgery, chemotherapy, radiotherapy, hormone therapy (endocrine therapy) or targeted therapy, either given alone or in any combination or order.
Surgery is usually the first treatment against breast cancer. This may be lumpectomy (breast conserving surgery), removal of the tumour and a small amount of surrounding tissue _or_ mastectomy, removal of the whole breast. The type, size and location of the cancer affects which surgery is most appropriate.
Women with invasive cancer undergoing lumpectomy or mastectomy also undergo removal of the first one or two lymph glands (sentinel nodes) from the armpit (axilla) to check if the cancer has spread to the lymph glands. This procedure is called sentinel node biopsy.
If the sentinel node(s) does not contain cancer cells, this usually means the other nodes are clear too, so no more nodes need to be removed. However, for about a quarter of women, the breast cancer has spread to their sentinel nodes. These women are recommendedarmpit treatment – further surgery to remove the remaining lymph glands or radiotherapy to the armpit (axilla). POSNOC trial is trying to find out whether armpit treatment is necessary.
Women undergoing mastectomy can undergo breast reconstruction at the same time as cancer-removing surgery, or months to years later. Some women decide not to have reconstruction or opt for a prosthesis instead.
Radiotherapy or radiation therapy is given to destroy cancer cells in the breast or chest wall that may persist after surgery. It consists of exposing the breast to focused and intense periods of radiation.
Treatment usually lasts 3 to 5 weeks with sessions in hospital every weekday. While women do not feel anything during the treatment, there may be some side effects to the treated area e.g. skin redness, itching, burning and soreness.
Chemotherapy is a drug treatment used to kill cancer cells in the body, including cells at the original cancer site and any cancer cells that may have spread to another part of the body. Chemotherapy is a systemic therapy, which means it affects the whole body by going through the bloodstream.Some patients will have it before surgery to shrink a tumour, although commonly chemotherapy is given after surgery.
There are lots of different chemotherapy drugs. In many cases, a combination of two or more drugs will be used as chemotherapy treatment for breast cancer.
Chemotherapy treatment can last for a few months as you will need to rest after each course of drugs.
The female hormone oestrogen can stimulate growth of breast cancers that have oestrogen receptors.
Hormone therapy blocks the effect of oestrogen on cancer cells by lowering the amount of the oestrogen in the body or blocking the action of oestrogen on breast cancer cells.
Hormonal therapy will not benefit women with oestrogen receptor negative breast cancers.
Targeted cancer therapies are treatments that target specific characteristics of cancer cells, such as a protein that allows the cancer cells to grow in a rapid or abnormal way. Targeted therapies are generally less likely than chemotherapy to harm normal, healthy cells.
Herceptin (trastuzumab) is an example of targeted therapy. It works against HER2-positive breast cancers by blocking the ability of the cancer cells to receive chemical signals that tell the cells to grow.