breast cancer information | What is breast cancer?

What is breast cancer?


Breast cancer takes birth in the breast cells. The cancerous tumor (malignant) is a group of cancerous cells that can invade and destroy the surrounding tissue. It can also spread (metastasis) to other parts of the body.

The cells of the breast sometimes undergo changes that make their mode of growth or their behaviour abnormal. These changes can lead to non-cancerous (benign) conditions of the breast, such as atypical hyperplasia and cysts. They can also lead to the formation of non-cancerous tumours, including Papillomas intracanalaires.

In some cases, however, changes in breast cells can cause breast cancer. Breast cancer appears most often in cells lining channels, which are tubes that carry milk from the glands to the nipple. This type of breast cancer is called ductal carcinoma. Cancer can also be formed in lobules cells, which are groups of milk-producing glands. This type of cancer bears the name of lobular carcinoma. Ductal carcinoma and lobular carcinoma may be in situ, i.e. the cancer remains in its original location and has not invaded the surrounding tissues. They may also be intrusive, or invasive, that is, they have invaded nearby tissues.

Less frequent types of breast cancer can also occur. Examples include inflammatory breast cancer, breast Paget disease and triple negative breast cancer. Rare types of breast cancer include non-Hodgkin's lymphoma and soft tissue sarcoma.

The Breasts
The woman and the man have breasts, but the woman has more breast tissue than the man. Breasts contain mammary glands. Only the mammary glands in women can produce milk to feed a baby. This is why the breasts are accessory organs of the female reproductive apparatus.

Diagram of the breast and its surrounding structures

The breasts are divided by an invisible line that goes from top to bottom and from left to right through the nipple. Each of these four regions is called Quadrant. Most breast cancers appear in the upper outer quadrant near the armpit since this area includes a lot of glandular tissue.

Structure
Each breast rests on a large chest muscle called pectoral grand muscle. The breast covers a rather large area: up to the clavicle and width, from the armpit (axillary trough) to the middle of the sternum approximately.

Parts of the breast
The breast is made of fat, connective tissue, glands and channels.

The ligaments are tight strips of connective tissue that support the breasts. They cross the breast of the skin to the muscles where they attach to the thorax.

Lobules are groups of glands that produce milk. Each breast has 15 to 25 lobules. The glands produce milk when they are stimulated by the hormones of the woman during pregnancy.

The channels are tubes that carry the milk from the lobules to the nipple.

The nipple is the area in the center of the areola and from where the milk comes out at one end. The nipple is made of muscle fibers. When these fibers contract, the nipple hardens, or points outward.

The areola is the round, pink or brown surface that surrounds the nipple. It contains small glands that release, or secrete, an oily substance that acts as a lubricant for the nipple and areola.