What Is Breast Cancer?

Breast cancer is a type of cancer forming in the cells of the human breast. It occurs when cells in the breast begin to grow and divide out of control forming a lump known as a tumor. In terms of breast cancer, it can begin in one or both breasts.

There are many different types of breast cancers. The main different types of breast are ductal carcinoma in situ (early form of breast cancer when cell lining of milk ducts become cancerous), invasive ductal carcinoma (when the cancer spreads beyond the milk ducts into the surrounding breast tissue), inflammatory breast cancer (rare but tough to fight as often has spread when found and occurs when cancer cells block lymphatic vessels covering breast), and metastatic breast cancer (when the breast cancer spreads beyond the breasts).

The exact cause of breast cancer is not known, but it is likely a mix of environmental and genetic factors. In terms of the genetic factors, only 10% of those with breast cancer have an inherited abnormal gene linked with the disease. The other 90%, however, have acquired abnormal genes meaning the mutations were not passed down. The most common cause of hereditary breast cancer are mutations in the BRCA1 or BRCA2 genes. In normal cells, these genes produce proteins which help with tissue repair, but in breast cancer, the mutated versions can trigger cells to spontaneously grow and divide forming a tumor. Environmental factors are also at play. Actions such as smoking or alcohol consumption increase one’s likelihood of developing breast cancer.