A woman's breast is made up of glands that make breast milk (called lobules), ducts (small tubes that carry milk from the lobules to the nipple), fatty and connective tissue, blood vessels, and lymph vessels. Most breast cancers begin in the cells that line the ducts (ductal cancer), some begin in the lobules (lobular cancer), and a small number start in other tissues. Breast cancer is found mostly in women, but men can also get breast cancer. Most breast lumps are benign. This means they are not cancer. Benign breast tumors are abnormal growths, but they do not spread outside of the breast and they are not life threatening. Most lumps are caused by fibrocystic changes. Cysts are fluid-filled sacs. Fibrosis is the formation of scar-like tissue. These changes can cause breast swelling and pain. They often happen just before a woman's period is about to start. The breasts may feel lumpy, and sometimes there is a clear or slightly cloudy nipple discharge.
Carcinoma: This is a term used to describe a cancer that begins in the lining layer of organs such as the breast. Nearly all breast cancers are carcinomas (either ductal carcinomas or lobular carcinomas).
Adenocarcinoma: An adenocarcinoma is a type of cancer that starts in gland tissue. The ducts and lobules of the breast are gland tissues because they make breast milk, so cancers starting in these areas are often called adenocarcinomas.
Carcinoma in situ: This term is used for the early stage of cancer, when it is still only in the layer of cells where it began. In breast cancer, in situ means that the cancer cells are only in the ducts (ductal carcinoma in situ) or lobules (lobular carcinoma in situ). They have not spread into deeper tissues in the breast or to other organs in the body. They are sometimes called non-invasive or pre-invasive breast cancers.
Invasive (infiltrating) carcinoma: An invasive cancer is one that has already grown beyond the layer of cells where it started (unlike carcinoma in situ).
Sarcoma: Sarcomas are cancers that start from connective tissues such as muscle tissue, fat tissue or blood vessels. Sarcomas of the breast are rare.
There is no sure way to prevent breast cancer. But there are things all women can do that may reduce their risk and help increase the odds that if cancer does occur, it is found at an early, more treatable stage.
Lowering your risk: If you limit alcohol use, exercise regularly, and stay at a healthy weight, you can decrease your risk of getting breast cancer. Women who choose to breast-feed for at least several months may also reduce their breast cancer risk.
Finding breast cancer early: It is also important for women to follow the American Cancer Society's guidelines for finding breast cancer early.
The most common sign of breast cancer is a new lump or mass. A lump that is painless, hard, and has uneven edges is more likely to be cancer. But some cancers are tender, soft, and rounded. So it's important to have anything unusual checked by a doctor.
The ACS recommends the following guidelines for finding breast cancer early in women without symptoms:
Mammogram: Women age 40 and older should have a screening mammogram every year and should keep on doing so for as long as they are in good health. While mammograms can miss some cancers, they are still a very good way to find breast cancer.
Clinical breast exam: Women in their 20s and 30s should have a clinical breast exam (CBE) as part of a regular exam by a health expert, at least every 3 years. After age 40, women should have a breast exam by a health expert every year. It might be a good idea to have the CBE shortly before the mammogram. You can use the exam to learn what your own breasts look and feel like.
Breast self-exam (BSE): BSE is an option for women starting in their 20s. Women should be told about the benefits and limitations of BSE. Women should report any changes in how their breasts look or feel to a health expert right away.
Women at high risk: Women with a higher risk of breast cancer should talk with their doctor about the best screening plan for them. This might mean starting mammograms when they are younger, having extra screening tests (such as an MRI), or having exams more often. If you have a higher risk for breast cancer there may be some things you can do to reduce your chances of getting breast cancer. These include;
Genetic Testing: There are tests that can tell if a woman has certain changed (mutated) genes linked to breast cancer. With this information, women can then take steps to reduce their risk. Recently the U.S. Preventive Services Task Force made recommendations for genetic testing. They suggest that only women with a strong family history be evaluated for genetic testing for BRCA mutations.
Breast Cancer Chemoprevention: Chemoprevention is the use of drugs to reduce the risk of cancer. Many drugs have been studied for use in lowering breast cancer risk. For more information please ask your doctor or visit the American Cancer Society Webpage.
Treatments can be put into broad groups based on how they work and when they are used. Local treatment is used to treat a tumor without affecting the rest of the body. Surgery and radiation are examples of local treatment. Systemic treatment is given into the bloodstream or by mouth and goes throughout the body to reach cancer cells that may have spread beyond the breast. Chemotherapy, hormone therapy, and targeted therapy are systemic treatments. When people who seem to have no cancer left after surgery are given more treatment it is called adjuvant therapy. Doctors now think that cancer cells can break away from the main tumor and begin to spread through the bloodstream in the early stages of the disease. It's very hard to tell if this has happened. But if it has, the cancer cells can start new tumors in other organs or in the bones. The goal of adjuvant therapy is to kill these hidden cells. But not every patient needs adjuvant therapy. Some people are given systemic treatment (most likely chemotherapy) before surgery to shrink a tumor. This is called neoadjuvant therapy.
http://www.cancer.org/Cancer/BreastCancer/index?ssSourceSiteId=null