Breast cancer is one of the most feared diseases by women today. In the United States, the American Cancer Society estimates that more than 180,000 new cases of breast cancer are diagnosed yearly. Almost 1 out of 8 women will develop breast cancer in her lifetime. Among them, more than one-fourth will die of the disease, making breast cancer the second most common cancer killer of women in the country, next only to lung cancer.
In the normal human body, the increase in number and size of your cells is tightly regulated. Every day, a certain number of cells die, and these dead cells are replaced by an appropriate number of new cells.
In certain conditions, it might be necessary for your body to regenerate an additional number of cells. For example, when you get pregnant, your body will release hormones and other growth factors that will instruct your breast glands to enlarge and to regenerate more cells in preparation for breastfeeding your baby. Once your breasts have sufficiently enlarged and are able to produce an adequate supply of milk, the proliferation of new breast cells also slows down until it reaches baseline level.
Breast cancer disrupts the normal growth cycle. An abnormal group of cells in your breast tissue begins to grow uncontrollably. These breast cancer cells increase in size and in number, even if your breast does not need to grow new cells. They also don't respond to your body's signals that should trigger cell suicide, causing them to live longer than normal cells do.
When enough of these abnormal cells have proliferated, they would form a lump that you might be able to feel on your breast. The mass might also be detected by your doctor during examination or seen on conventional and magnetic resonance mammography. But if undetected, this group of abnormal cells grows even more.
The breast tumor forms blood vessels that deliver nutrients stolen from your normal cells, and releases chemicals that might cause weight loss, fever or fatigue. It will invade adjacent structures such as your nipple, the skin overlying your breast, the ligaments that attach your breast to your chest wall and the lymph nodes that normally clear harmful microorganisms from your body. In advanced cases, breast cancer cells spread to distant structures such as your lungs and brain by traveling through your blood and lymph vessels.
There are several risk factors that lead to the transformation of normal breast cells to abnormal cancer cells. Genetic abnormalities in the BRCA1 or BRCA2 gene are the best-known causes of hereditary breast cancer. You have a higher risk of developing breast cancer if you inherited mutations in these genes.
Women who had their first menstruation before age 12 or who had menopause after age 55 are also at a higher risk for breast cancer. The same is true for women who have never given birth or those who delivered their first child later than age 35. The roles of hormone replacement therapy, oral contraceptives, obesity, a high fat diet, alcohol consumption and cigarette smoking in the development of breast cancer are less established and are still under debate.
Tags: your breast, breast cancer, breast cancer, your body, cancer cells, number cells, abnormal cells
