How common is breast cancer?

Breast cancer is very common. Apart from minor skin cancers, breast cancer is the most common cancer in Canadian women. An estimated 19 000 women had breast cancer in 1999. Until 1992, breast cancer was the most common cause of cancer deaths in women. Since then, breast cancer is the second-most common: lung cancer has taken over as the most common cancer in women, a legacy of increased smoking rates in the 1960s and 1970s.

What are the risk factors for breast cancer?

The most important risk factor for breast cancer (other than gender) is increasing age. Breast cancer is most often diagnosed in women over age 50. You are more likely to develop breast cancer if you have a family history of breast cancer, are obese, had radiation exposure to the chest, have had no children, live in an urban area, or were born in North America or Northern Europe. Hormone replacement therapy (estrogen), given after menopause, has also recently been shown to slightly increase the risk of breast cancer.

How can breast cancer be caught early?

Many of the risk factors for breast cancer are factors that you cannot change – your age, your ethnic ancestry, your family history. Because of this, a strong emphasis has been put on early detection.

Breast self-examination is often recommended as a means of early detection, and is done regularly by many women. Some doctors feel it is an inaccurate screening test and fear that it can lead to unnecessary biopsies – other physicians recommend that you do self-examination every month.

The only early detection tool that has been definitely proven to save lives is mammography, or breast X-rays. If you are between 50 and 69 years old, you should be getting mammography regularly – talk to your doctor or phone your local screening centre for an appointment.

If I have breast cancer, how will it be treated?

Treatment for breast cancer can involve any of the general types of treatment that are used for other cancers. The specific treatment suggested for you will depend on the size of the tumour, your age, the presence of any spread of the cancer to other parts of your body and characteristics of the cancer itself. Your cancer specialist will be in the best position to judge these factors, and offer a treatment plan specifically tailored for you.  Breast cancer can be treated with any or all of the following treatment options.

Surgery is almost always an early part of treatment. The trend has been to smaller operations, removing your cancerous lump with a small amount of surrounding tissue rather than the whole breast. The operation usually involves removing lymph glands from the armpit (axilla) on the same side, because this is where the cancer spreads first.

Radiation treatment is often given soon after surgery to destroy any cancer cells left behind after surgery or that may have spread to the rest of your breast or to your other breast before surgery.

Chemotherapy is not always, but often, given after surgery. Again, the intent of chemotherapy is to seek and destroy cancer cells that have escaped to some other part of your body.

The final treatment that is usually given is hormone treatment. Because the breast is a hormone-responsive organ, many breast cancers respond to the presence or absence of female hormones. Special tests done on the removed cancer can determine whether hormone therapy will be an adequate treatment for your cancer.