Types of breast cancer
There are several different types of breast cancer, which can develop in different parts of the breast. Breast cancer is often divided into non-invasive and invasive types.
Non-invasive breast cancer
Non-invasive breast cancer is also known as carcinoma in situ, or pre-cancerous cells. This cancer is found in the ducts of the breast and has not developed the ability to spread outside the breast. This form of cancer rarely shows as a lump in the breast and is usually found on a mammogram.
Invasive breast cancer
Invasive cancer has the ability to spread outside the breast, although this does not mean it necessarily has spread. The most common form of breast cancer is invasive ductal breast cancer, which develops in the cells that line the breast ducts. Invasive ductal breast cancer accounts for about 80% of all cases of breast cancer and is sometimes called 'no special type'.
Other types of breast cancer
Other less common types of breast cancer include invasive lobular breast cancer, which develops in the cells that line the milk-producing lobules, inflammatory breast cancer and Paget's disease of the breast. It is possible for breast cancer to spread to other parts of the body, usually through the lymph nodes (small glands that filter bacteria from the body) or the bloodstream. If this happens, it is known as secondary or metastatic breast cancer.
The exact cause of breast cancer is not fully understood, but many factors increase the likelihood of developing it, including age and family history of breast cancer.
Women who have a higher-than-average risk of developing breast cancer may be offered screening and genetic testing for the condition. As the risk of breast cancer increases with age, all women aged 50–70 are invited for breast cancer screening every three years. Women over 70 are also entitled to screening and can arrange an appointment through their GP or local screening unit.
Breast cancer can be treated using a combination of surgery, chemotherapy and radiotherapy. Some cases of breast cancer may also be treated using biological or hormone treatments.
One in eight women are affected by breast cancer during their lifetime. There is a good chance of recovery if it is detected in its early stages. For this reason, it is vital that women check their breasts regularly for any changes and always get any changes examined by their GP.