Definition of Breast Cancer
Breast cancer can be defined as a cancerous growth that inhabits the tissues in the breast. In this type of cancer, the cells in the breast region grow abnormally and in an uncontrolled way. Though breast cancer is mostly found in women, in rare cases it is also found in men. In the U.S. alone one out of every eight women has this disease.
Breast cancer is the most common form of cancer in women and the second most common cause of cancer death for women in the U.S. While the majority of new breast cancers are diagnosed as a result of an abnormality seen on a mammogram, a lump or change in consistency of the breast tissue felt with the fingertips can also be a warning sign of the disease. Heightened awareness of breast cancer risk in the past decades has led to an increase in the number of women getting mammograms. Breast cancers are being detected in earlier stages and survival rates are going up. Still, breast cancer is the most common cause of death in women between the ages of 45 and 55. Although breast cancer is more common in women, it does occur in men. Male breast cancer accounts for about 1% of all cancer deaths in men.
Research has yielded much information about the risk factors and causes of breast cancer, and it is now believed that genetic and/or hormonal factors are the primary risk factors. Staging systems have been developed to allow physicians to characterize the extent to which a particular cancer has spread and to make decisions concerning treatment options. Breast cancer treatment depends upon many factors, including the type of cancer and the extent to which it has spread. Treatment options for breast cancer may involve surgery (removal of the cancer alone or, in some cases, mastectomy), radiation therapy, hormonal therapy, and/or chemotherapy.
Symptoms of Breast Cancer
There are several symptoms of breast cancer. Women need to be aware of these so that an early diagnosis can be made. Early detection increases the rate of recovery. Some of the symptoms of breast cancer are:
- Increasing swellings or lumps in the breast or in the armpit. Though this may also be due to hormonal changes, it is important to see your physician for a breast exam.
- Changes in the size and shape of the mature breast, especially if it is prominently noticed in one breast.
- Fluid, not milk, leaking from the nipple, especially in older women.
- Noticeable changes occurring in the size and shape of the nipple or a nipple that does not easily return to its normal shape.
Symptoms can be caused by cancer or by a number of less serious conditions. Early diagnosis is especially important for breast cancer because the disease responds best to treatment before it has spread. The earlier breast cancer is found and treated, the better a woman's chance for complete recovery.
Types of Breast Cancer
There are primarily two types of breast cancer to be found in most women. These types of breast cancer are named after the parts of the breast in which they start. They are:
- Ductal Carcinoma Breast Cancer - It starts in the cells which line the breast's ducts, beneath the nipple and areola. The ducts supply milk to the nipple. Between 85% and 90% of all breast cancers are ductal. If the cancer is DCIS (ductal carcinoma in situ), it is well contained, not invasive, and can be very successfully treated. Usually removed during a lumpectomy, if the tumor margins are clear of cancer, follow-up treatment may include radiation. If ductal cancer has broken into nearby breast tissue (invasive cancer) then a mastectomy may be needed, and your physician may also recommend chemotherapy.
- Lobular Carcinoma Breast Cancer - It begins in the lobes or glands which produce milk in the breast. The lobes are located deeper inside the breast, under the ducts. About 8% of breast cancers are lobular. If the cancer is LCIS (lobular carcinoma in situ) that means the cancer is limited within the lobe and has not spread. It may be removed during a lumpectomy, if the tumor margins are clear of cancer, and follow-up treatment may include radiation. If lobular cancer has spread into nearby breast tissue (invasive cancer) then a mastectomy may be needed, and your physician may also recommend chemotherapy.
One of the rarest forms of breast cancer is named for its appearance.
- Inflammatory Breast Cancer - It is the least common, but most aggressive of breast cancers, taking the form of sheets instead of lumps. The breast may feel warm, and be red and swollen. It can also feel tender or itchy. It can start in the soft tissues of the breast, just under the skin, or it can appear in the skin. Unlike ductal and lobular cancers, it is treated first with chemotherapy and then with surgery. When caught early, inflammatory breast cancer can be a manageable disease and survival rates are increasing. But because there are usually no lumps the cancer often isn't detected until it has progressed.
Least common is cancer of the nipple, named for Sir James Paget who first noticed the relationship between changes in the nipple and the underlying breast cancer.
- Paget's Disease of the nipple/areola often looks like a skin rash, or rough skin. It resembles eczema, and can be itchy. The itching and scabs (if scratched) are signs that cancer may be under the surface of the skin, and is breaking through. Paget’s is usually treated with a mastectomy, because the cancer has by then invaded the nipple, areola, and the milk ducts.
Causes of Breast Cancer
Though the exact causes of breast cancer are largely unknown, research has found some probable causes of breast cancer.
Family history has long been known to be a risk factor for breast cancer. Both maternal and paternal relatives are important. The risk is highest if the affected relative developed breast cancer at a young age, had cancer in both breasts, or if she is a close relative. First-degree relatives, (mother, sister, daughter) are most important in estimating risk. Several second-degree relatives (grandmother, aunt) with breast cancer may also increase risk. Breast cancer in a male increases the risk for all his close female relatives. Having relatives with both breast and ovarian cancer also increases a woman's risk of developing breast cancer.
There is great interest in genes linked to breast cancer. About 5%-10% of breast cancers are believed to be hereditary as a result of mutations, or changes, in certain genes that are passed along in families.
- BRCA1 and BRCA2 are abnormal genes that, when inherited, markedly increase the risk of breast cancer to a lifetime risk estimated between 40% and 85%. Women with these abnormal genes also have an increased likelihood of developing ovarian cancer. Women who have the BRCA1 gene tend to develop breast cancer at an early age.
Some other probable causes and risk factors are:
- Advancing age
- Excessive exposure to radioactive rays
- Hereditary genes or family history
- Late childbearing
- The use of hormone replacement therapy
- Early onset of a menstrual cycle and an early menopause
- Men or women working in chemical factories