Breast cancer is very common, with one in twelve women in Britain developing the disease. There are two issues, the first being how to treat cancer in the breast itself and the second, how to reduce the risks of recurrence in other sites.
Metastasis, meaning 'change of place', occurs when cancer cells break off and spread through the lymphatic channels or blood vessels to settle in other parts of the body. It is particularly common with breast cancer, usually spreading through the lymph nodes in the axilla (armpit). Secondary tumours can form in the bone, liver, lung and less frequently the brain. Around 80% of patients developing early breast cancer will be cured of their disease. Those that are not developed recurrence and spread in other sites of the body.
Breast cancer symptoms and screening
The most common way for women to notice breast cancer is to find a painless lump while bathing. Other symptoms include:
- Change in shape or size of the breast.
- Change in the appearance or feel of the skin on the breast.
- Rash on the nipple.
- Discharge from the nipple.
- Inverted nipple (turned in nipple).
- Lump or swelling in the armpit.
Screening has increased the detection of early cancer, but there is considerable controversy as to how worthwhile it is. As well as identifying cancer, screening also picks up many minor abnormalities that do not need treatment. This creates a great deal of anxiety for the patient and their families and sometimes outweighs the benefit of a slightly earlier diagnosis.
The initial assessment of a patient suspected of having breast cancer includes a careful examination to assess the size, location of character of the primary tumour, together with evidence of spread to the lymph nodes in the axilla and other areas around the breast.
Investigations required to fully assess a patient with early breast cancer may include a blood count, liver function tests, chest x-ray/mammography, ultrasound and a bone scan. Other types of scanning may be requested if abnormalities are found on clinical examination or there are symptoms that suggest the disease may have spread. Some patients present with disease that has already spread, often to the bone.
There are four treatments for breast cancer - surgery, radiotherapy, chemotherapy and hormone treatment.
In 1895 William Halstead, a pioneering American surgeon developed an operation called the radical mastectomy. This became the archetype of many cancer operations. The primary tumour in the breast was removed with surrounding tissue in contiguity with the regional lymph nodes and underlying muscle.
Over the last decade, the thrust has been towards more conservative surgery, where the tumour alone is removed, usually with a one to two-centimetre margin. The patient is then given postoperative radiotherapy. This approach gives a better cosmetic result with no evidence of an increased rate of local recurrence or poorer survival when compared with more aggressive surgical procedures.
It is not always possible to use this conservative approach, however. If there is a large tumour in a small breast and its removal would result in a poor cosmetic appearance, or if there are several tumours in the breast (in about 10% of cases), a mastectomy may be necessary. Alternatives are always discussed with patients and they form part of the decision-making process.
Radiotherapy is used in conjunction with surgery to prevent the disease returning within the breast. It must be planned carefully and delivered using advanced equipment. We know that the long-term results of surgery and radiotherapy can be excellent. However, if radiotherapy is given using old-fashioned techniques, fibrosis and other late side effects occur as a result of damage to normal tissue surrounding the tumour's bed.
Because of the breast's unusual shape in three dimensions and the inability to use a template due to variation among women, determining the correct technique for irradiating an individual breast is a very skilled process. GenesisCare uses image-guided radiotherapy (IGRT) and intensity modulated radiotherapy (IMRT) to precisely target the tumour and avoid damage to healthy tissue.
Radiotherapy may also be used if breast cancer recurs outside the previously treated volume and is localised.
Deep inspiration breath hold (DIBH) radiotherapy
GenesisCare is in the process of conducting a significant piece of research into spirometry-monitored deep inspiration breath-hold radiotherapy (DIBH). This type of treatment is designed to be more accurate than other treatments available and to minimise risk to other vital organs in the body.
The GenesisCare Research and Development team has released findings from an interim study looking at 42 patients' data sets and the positive effects spirometry-monitored DIBH can have on long-term cardiovascular issues and risk of death for the patient. So far, the research has revealed some significant findings - all of which can be found in this whitepaper.
Chemotherapy for treatment of primary breast cancer
Chemotherapy is used as an adjuvant for primary breast cancer, ie. additional treatment after apparently successful removal of all known disease detectable by clinical x-ray and other investigations.
When the primary tumour is removed, access to any small areas of spreading cells is good and remaining tumour cells should theoretically be sensitive to chemotherapy as they are dividing at their most rapid rate. The patient should tolerate even aggressive regimens as she is not in poor health due to the effects of large metastases.
There is good evidence from tumour model systems to support the role of adjuvant chemotherapy in preventing recurrence. In the 1970's two large published studies showed that chemotherapy given for a year following surgery had a dramatic effect on long-term survival. Over the years the drugs have changed and become much more tolerable. They are also given with supportive drugs to prevent sickness and other side effects, Revo have really revolutionised adjuvant treatment of breast cancer. The drugs that are commonly used are 5 Fluorouracil, Epirubicin, Adriamycin, Cyclophosphamide, Herceptin, Docetaxel and Taxol.
Breast cancer has provided a valuable test ground for trials of adjuvant treatment in both chemotherapy and hormones for treatment of other cancers.
Chemotherapy for treatment of recurring breast cancer
Chemotherapy is also offered where breast cancer has recurred. The same agents used for adjuvant treatment are given and the patient is closely monitored after two or three cycles. The most important part of a management plan is to check the tumour is actually disappearing in response to chemotherapy. This often takes two to three months and therefore a critical re-assessment is needed. A difficult clinical problem arises when chemotherapy is only partially effective. The physician and patient must then balance the benefits in terms of tumour response with the drawbacks arising from the side effects of therapy.
Hormone treatment, like chemotherapy, is used in both adjuvant and metastatic situations. A variety of drugs is available including Tamoxifen, Anastrozole, Letrozole and Exemestane. All suppress the oestrogen drive for cancer cells by affecting the hormonal composition of the body. Most patients will have few side effects. Tamoxifen is much less used now but was the first anti-oestrogen drug to be discovered in the UK in the 60's. It led to a plethora of drugs that are more effective in some cases, especially in post-menopausal women.
There have been huge advances in the treatment of breast cancer over the last fifty years and this is reflected in much better survival rates. The increased awareness of breast cancer has led to more women seeing their doctors with the early disease. This makes treatment much easier for both doctor and patient. The message must be not to ignore a breast lump, however, innocuous it seems.
Find out more about the treatment of breast cancer using our radiotherapy.