What is breast cancer?

Breast cancer is a disease that occurs when cells in the breast tissue change (or mutate) and keep rapidly dividing. These abnormal cells usually group together to form a tumor. A tumor can become cancerous (malignant) when such abnormally growing cells show the ability to spread to other parts of the breast, or to other areas of the body (metastasize) via the bloodstream or via the lymphatic system (a network of blood vessels and lymph nodes in the body, that helps the body in fighting infections).

Breast cancer generally begins in the lobules (milk-producing glands of the breast), or in the tube-shaped ducts that carry milk from the lobules to the nipple. Sometimes, breast cancer begins taking shape in the fatty and fibrous “connective tissue” within the breasts.

Breast cancer is the most common cancer in women, and one of the leading causes of cancer-related deaths in women around the world. It is most commonly seen in women aged more than 50 years.

Anyone who has breast tissue (even a man) is at risk of developing breast cancer, although breast cancer is 100X more common in women than men.

Female breast anatomy in the study of breast cancer

The death rate from breast cancer has declined in recent years, due to greater awareness and screening, as well as better treatment options.

How does breast cancer occur?

Breast cancer begins with a genetic mutation in the DNA of breast cancer cells. Some of these mutations may develop randomly over time (the human body is constantly mutating and fixing itself), some mutations are hereditary (genetic predisposition), and some are sporadic – caused by environmental exposure or lifestyle-related risk factors.

See further:

What are the risk factors that can cause breast cancer?
What are the best ways to prevent breast cancer?
What are the types of breast cancer?
What are the hormone receptor-based subtypes for breast cancer?
How is breast cancer staged?
Stage 0 breast cancer
Stage 1 breast cancer
Stage 2 breast cancer
Stage 3 breast cancer
Stage 4 breast cancer
Treatment of breast cancer
Things to know before treating breast cancer
Survival rates for breast cancer patients
Side effects of breast cancer treatment


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