What is Breast Cancer?
The first microscopic section at the left is an example of in situ cancer. Cancer cells have not moved beyond the outer lining. The second section is an example of invasive cancer. Cancer cells have broken through the outer lining.
Breast cancer is the most common form of cancer diagnosed in women. Cancer is a term used to describe diseases in which the body’s cells become abnormal and divide without control. The abnormal cells may spread to other parts of the body through direct invasion (cell to cell) or by means of the bloodstream and lymph nodes. As cancer progresses, it can lead to injury and sometimes death. Breast cancer starts in the breast and can affect women and men.
Breast cancers are either non-invasive or invasive. Non-invasive breast cancer is the kind confined within the ducts or lobules of the breast. It also is referred to as ductal cancer in situ (DCIS) or lobular cancer in situ (LCIS). Some experts feel LCIS is not truly a cancer, but a marker for risk of developing a future breast cancer. Invasive (also referred to as infiltrating) breast cancer is the type that has broken through the normal breast tissue barriers, has invaded surrounding tissues, and has the potential to spread to distant places in the body.
The first microscopic section at the left is an example of in situ cancer. Cancer cells have not moved beyond the outer lining. The second section is an example of invasive cancer. Cancer cells have broken through the outer lining.
Causes of Breast Cancer: Common Factors
A variety of factors have been found to be more commonly associated with the risk of development of breast cancer including have a family history of breast and/or ovarian cancer, increased exposure to hormones, genetic factors, obesity, prior radiation exposure to the chest during adolescence or young adulthood, history of previous abnormal breast biopsies and some poor lifestyle habits including high-fat diets and limited to no regular exercise. The most common associations that remain consistent for risk of breast cancer is advancing age (highest risk group for development of breast cancer in the world are those women who are over 60 years of age) and being female.
Genetic Risk: Genes and the Risk of Breast Cancer
Most breast cancers appear to occur sporadically — no known cause of why the process occurred. However, it is currently understood that about 10-15% of all breast cancers are linked to mutations of breast and ovarian cancer genes known as the BRCA1 & BRCA2 genes. If these genes mutate (mistakes that occur in the DNA structure), a person’s lifetime risk for development of breast cancer is significantly higher than women who do not acquire these kinds of gene mutations.
You may be asked to have this testing done on your blood to determine if you carry such a mutation. Women that do carry these mutations are prone to development of breast cancer in both breasts (bilateral breast cancer) and ovarian cancer as well. Clearly, if a person is identified as carrying the genes, treatment with more surgery including breast mastectomy (removal of the breast) and ophorectomy (removal of the ovaries) may be considered. It is important to know that having a gene mutation like this is fairly rare and unless you have significant risk factors such as an early age of diagnosis of breast cancer or a strong family history of breast or ovarian cancer, you are unlikely to carry such a gene mutation. This is a very complex issue and further information about gene testing as it applies to your situation should be discussed with your physician(s).
