CIBC Breast Centre

Breast Cancer

Breast cancer is the most common type of cancer for women. We don’t know what causes breast cancer, but some of the things we think increase your chances are:

  • A family history of breast cancer
  • Environmental carcinogens (any substance that can cause or aggravate cancer)
  • Life-style factors (diet and hormonal function)

Carcinoma refers to a malignant or cancerous growth of cells. Cancer begins when normal cells stop working properly and begin to grow abnormally. This process doesn't occur in a day, or in a week, or in a month, or even in a year. It often takes decades or more for a normal cell to get the necessary things to start acting like a cancer cell. Cancer cells often show up in the areas of the breast that produce and transport milk, like the lobules and the ducts. When cancer cells are contained in these structures they are said to be 'in situ' (from Latin meaning "in its own situation"). 'In situ' cancers are the very earliest and most treatable types of cancer.

Lobular Carcinoma In Situ (LCIS)

LCIS is not an actual cancer. It is considered to be a sign that you may be at a higher risk of developing breast cancer. Most times it is found by accident in breast biopsies. Both breasts are then at a higher risk of developing breast cancer. Usually LCIS is treated by regularly observing your breasts using a mammogram once a year, and going for a clinical breast exam twice a year. Some women with LCIS consider taking tamoxifen to prevent breast cancer and some have a bilateral prophylactic mastectomy surgery (the preventative removal of both breasts).

Ductal Carcinoma In Situ (DCIS)

This is the earliest stage (stage 0) of breast cancer, when the cancer is confined to the breast ducts. Of all the breast abnormalities that are detected by the OBSP, 20 per cent are DCIS and 16 per cent take place at follow-up screenings. If the cancer is caught at stage 0, the success of the treatment is nearly 100 per cent. If cells are left to change and spread, the cancer can get into the surrounding tissues and become a type of invasive breast cancer.

Infiltrating (invasive) Lobular Carcinoma (ILC)

This cancer starts in the lobules or milk glands and can spread to other parts of the body. It is often difficult to feel or see on a mammogram. ILC makes up about 10 to 15 per cent of all breast cancers.

Infiltrating (invasive) Ductal Carcinoma (IDC)

Invasive means the cancer has started to spread or "invade" into the nearby breast tissue. Ductal means that the cancer started in the milk ducts (or pipes) that carry milk from the lobules (place where milk is made), to the nipple. Carcinoma means that the cancer started in the skin or other tissues that cover internal organs, like the breast tissue. All together, "invasive ductal carcinoma" refers to the cancer that has broken through the wall of the milk duct and started to spread into the tissues of the breast. As the cells begin to grow, they begin to create thick breast lumps that can sometimes be felt on a breast self-exam.

Even though cancer cells have moved into the milk duct and breast tissue, it does not mean that cancer has spread into other parts of the body (metastases). However, if IDC is left untreated, it can begin to spread.

IDC is the most common invasive breast cancer. Sometimes it is also called infiltrating ductal carcinoma or mammary carcinoma. About 80 per cent of all breast cancers are invasive ductal carcinomas.

Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is a not a common type of breast cancer. It grows and spreads quickly, even in the beginning stages. Cancer cells begin to block the lymph vessels in the skin. This stops the lymph vessels from being able to remove fluid, bacteria and other waste products from the breast tissue. The breasts can then become inflamed (red and swollen). IBC tends to grow in layers or nests, not like most common types of breast cancers. Symptoms can appear suddenly, including a change in the size or shape of your breast, breasts that are hot or itchy to the touch, a change in the normal colour of your breasts, or a change in texture. The skin can also have a pitted appearance similar to the skin of an orange.

Many breast lumps and changes are not actually cancer, but are benign conditions, tumours or cysts. However, it is important to have any new lumps checked by your doctor as soon as possible.