Introduction
It has become a popular fashion statement to support different charities or organizations by wearing ribbons or the even more popular wrist bands. Perhaps the most notable are the yellow wrist bands started by Lance Armstrong to support his charity. However, if you take a close look you will see that many people are showing their support for breast cancer by wearing pink ribbons and bracelets. Breast cancer has unfortunately become so widespread that nearly everyone knows someone that has suffered from this terrible form of cancer.
What is it?
Each month, a woman's breast goes through changes associated with menstruation that can cause a lump to form. While the majority of these lumps are benign (or non-cancerous), each lump should be examined. Lumps are most commonly formed in breast tissue lobules, (small sacs that produce milk), or the ducts that carry milk to the nipple. However, lumps can also form in other breast tissue.
When a lump is found to be malignant, breast cancer is diagnosed. Breast cancer is divided into two main categories: lobular and ductal carcinomas. Breast cancer is also categorizes as non-invasive or invasive.
Breast cancer typically starts with the formation of a small confined tumor. Some tumors are benign, thus not invading other tissue; other are malignant or cancerous. These malignant tumors have the ability to metastasize, which means they spread to other tissues or regions in the body. The larger a tumor grows, the more likely it is that small pieces or cells will break off and spread to other parts of the body through the bloodstream or lymph system. Different types of breast cancer grow and spread at different rates; some may take years, while others may grow and spread much more quickly.
Four Main Types of Breast Cancer Exist:
Invasive Ductal Carcinoma (IDC): Invasive ductal carcinoma (also known as IDC) is the most common form of invasive breast cancer accounting for 75 percent of all invasive breast cancers. These tumors commonly spread to lymph nodes in the armpits. IDC is typically an aggressive cancer and has an increased risk of death compared to other types of invasive breast cancers. IDC metastasizes commonly to different areas of the body including bone, the liver, lung or brain
Invasive Lobular Carcinoma (ILC): Another type of invasive breast cancer is known as invasive lobular carcinoma (or ILC), which accounts for 5 to 10% of breast tumors. ILC more commonly spreads or metastasizes to unusual sites such as the layers that cover the brain and surfaces that cover organs.
Ductal Carcinomna In Situ (DCIS): A form of breast cancer that is non-invasive is known as ductal carcinoma in situ (DCIS). DCIS is the most common type of non-invasive breast cancer and is diagnosed when cancerous cells line the ducts in the breast. "In situ" means that the cancer cells have not spread beyond the ducts. However DCIS can progress and become invasive, especially if not detected early. Most cases of DCIS cannot be felt as lumps or masses but will show up on mammograms?one reason why regular mammograms are a must.
Lobular Carcinoma In Situ (LCIS): Lobular carcinoma in situ (or LCIS) is another form of non-invasive breast cancer. LCIS is a benign tumor that consists of abnormal cells in the lining of the lobule. "In situ" means that the abnormal cells have not spread beyond the lobules. LCIS is not actually considered cancer?it is generally thought to be a 'pre-cancer." LCIS will typically not show up on a mammogram. The only means of detecting LCIS is by taking sample of the suspected tissue and examining it in a lab. It is currently unclear whether or not LCIS progresses to cancer.
Breast cancers, just like other cancers are also categorized or "staged" based on the following system called the "TNM" rating:
- A "T" refers to the size of the tumor. Tumors are graded on a scale of one to four, with four being the most advanced.
- An "N" refers to how much the cancer has affected the lymph nodes, which exist throughout the body. Lymph node involvement is graded on a scale of zero to three, with three having the most lymph node involvement.
- An "M" rating is used to identify if the cancer has spread, which is referred to as "metastasized." Metastases are assigned a zero if the tumor has not spread or a one if it has.
Once the cancer begins to spread, getting rid of it completely is more difficult, although treatment can often control the disease for years. Improved screening procedures and treatment options mean that at least seven out of 10 women with breast cancer will survive more than five years after initial diagnosis, and half will survive more than 10 years.
Fortunately, breast cancer is very treatable if detected early. Localized tumors can usually be treated successfully before the cancer spreads; and in nine in 10 cases, the woman will live at least another five years. Experts usually consider a five-year survival to be a cure.
What causes it?
Although the exact cause of breast cancer is unknown, we do know the main risk factors that put people at risk. Most current evidence indicates that hypersensitivity of estrogen and/or progesterone-specific receptors within breast tissue are responsible for the majority of breast cancer cases. It is believed that these two hormones may be responsible for proliferation of breast cells and resultant tumor formation. For example, estrogen tells cells to divide; the more the cells divide, the more likely they are going to become abnormal in some way and possible cancerous.
Additionally, the mutations of two abnormal hereditary genes, BRCA1 and BRCA2, have been found to play an important role in the development of breast cancer. It is estimated that about 1 in 200 women carries these genes and are therefore at a substantial greater risk for developing breast cancer.
Who has it?
Among women, breast cancer is the most common cancer and the second leading cause of cancer death, only second to lung cancer. Nearly 200,000 women in the United States will be diagnosed with invasive breast cancer in 2007. It is also estimated that there will be over 40,000 deaths due to breast cancer in 2007. This mortality rate may seem high, but mortality rates have been decreasing every year since 1989. This decline is thought to be due to improvement in cancer treatments and improvement in prevention and early detection techniques.
The incidence of breast cancer begins in early adulthood, with a sharp rise in incidence to the time of menopause. After menopause, the incidence of cancer decreases significantly.
If eight women were to live to be at least 85, one of them would be expected to develop the disease at some point during her life. Two-thirds of women with breast cancer are over 50, and most of the rest are between 39 and 49.
Breast cancer is not a disease that affects only women. One percent of all breast cancers occur in men. According to the American Cancer Society, over 2000 men in the United States will be diagnosed with breast cancer in 2007.
What are the risk factors?
Several risk factors have been identified as having a potential relationship to the development of breast cancer. These include:
- Advanced age
- Personal or family history of breast cancer
- Menstrual periods beginning at an early age (before age 12)
- Abnormal BRCA1 and BRCA2 genes (genetic testing can identify if you carry these genes)
- Late menopause (after age 55)
- Never having children
- Having first child after age 30
- Obesity (especially noted in postmenopausal women)
- Long term use of postmenopausal hormone replacement therapy (greater than 5 years)
- Benign breast disease
- Oral contraceptive use(however recent studies have shown this to not be as significant as once thought)
- Alcohol consumption
- Having received radiation before age 40
Since most of these risk factors are not easily modified, early detection is very important. The American Cancer Society recommends a breast self examination (BSE) monthly for all women older than 20, a Clinical Breast Exam (performed by a healthcare professional) every 3 years (from ages 20-39), and a Mammogram annually for women older than 40.
What are the symptoms?
Symptoms of breast cancer can vary based on the severity of the disease. The most common initial sign of breast cancer is abnormalities on mammograms. These abnormalities can often show long before a woman or her doctor detects any physical changes in the breast.
There are specific factors that should raise suspicion of disease. These include:
- A lump noted on breast self-examination (BSE)
- A thickening or swelling of the breast or nipple
- A discharge from the nipple
- Swelling in the armpit
- More advance stages will show a change in contour, texture, size, or warmth of the breast
How is it treated?
The most important treatment for breast cancer is early detection. Starting around age 20, women should perform monthly self breast examines to check for any new masses or lumps. Contact your doctor immediately if you detect a lump or mass or your breast(s) is painful or abnormally shaped. Also, contact your doctor if you notice any swelling in your armpits, which could also be associated with cancer.
The type of treatment that is chosen for a person with breast cancer is based on several factors, and the individual should work closely with the health care provider to determine the best treatment approach. The decision for treatment is made based on the size and location of the mass in the breast, lab tests performed on the cancer cells, and the stage or extent of the disease. The care given may consist of chemotherapy, radiation therapy, surgery, and hormone therapy or a combination of treatments.
Most individuals with breast cancer will have some type of surgery. Surgery for breast cancer includes either a mastectomy, full removal of the breast, or lumpectomy, which preserves the breast and only removes the lump. Each of these procedures can also be done with or without removal of lymph nodes. Treatment regimens may be used to prevent the spread of breast cancer to the opposite breast and to reduce the incidence of breast cancer.
The U.S. Preventive Services Task Force is urging health professionals to recommend tamoxifen or raloxifene to women at high risk for developing breast cancer to prevent the disease (chemoprevention). This agency is also advising that women at low or average breast cancer risk should not take these medications for chemoprevention due to adverse effects.
Drug classes used to treat Breast Cancer
- Anti-estrogens
- Aromatase Inhibitor
- Monoclonal Antibodies
- Progestins
The FDA recently approved Avastin (also known as bevacizumab) to be used in combination with Taxol (also known as paclitaxel) to treat women with advanced breast cancer who have not started chemotherapy. Studies showed that this combination increased the time that breast cancer did not progress. Avastin is a new class of drugs that block the formation of blood vessels that supply the cancerous tumors, thus eliminating the source of nutrition for the cancer cells.
The American Cancer Society has funded more than 184 research projects relating to breast cancer. A few areas of research include:
- Anti-angiogenesis drugs - These drugs are theorized to block the supply of new blood vessels to breast tumors.
- New molecular targets for anticancer drugs
- Gene therapy - an area of interest to many researchers. The idea here would be to replace the defective genes in cancer cells with normal, healthy genes, thereby correcting the cells' overactive replication problem. The challenge is finding a way to get the healthy genes into the cancer cells.
- The effect of presurgery hypnosis on side effects, recovery, and cost of breast cancer treatment
- How a woman's genetic makeup determines her response to treatment
- Causes of breast cancer - The Sister Study is following 50,000 women ages 35-74 whose sisters (not themselves) have had breast cancer for 10 years to try to identify causes of breast cancer.
- Immunotherapy - vaccines containing specific antigens (particles that generate an immune response) located on the surface of the breast are currently being studied.
There are currently more and more studies that are examining the effects of lifestyle factors and habits that can alter breast cancer risk. Many studies are looking into the effects of exercise, weight gain or loss, and diet on the risk. With the sequencing of the human genome, the advances in breast cancer prevention and treatment related to genes will continue to accelerate.
