Breast Cancer: Everything You Need to Know

breast cancer support group — Thanks to fundraising, screening and greater awareness, breast cancer death rates have fallen dramatically over the past three or four decades. Steve Debenport/Getty Images

In 1991, runners participating in the New York City Race for the Cure, sponsored by the Komen Foundation, were handed pink ribbons. The next year, Estée Lauder offered the pink ribbons to Self Magazine readers in conjunction with the National Breast Cancer Awareness Month issue. Since these events in the early 1990s, the pink ribbon has become a ubiquitous symbol of breast cancer.

Breast cancer is the second most common cancer diagnosed in women in the United States, after skin cancer. In 2019, 264,121 women in the U.S. were diagnosed with breast cancer, and 42,280 women lost their lives to the disease [source: CDC]. Despite these frightening statistics, there's evidence that those pink ribbons are doing their job in raising awareness of the condition and spurring donations that are used to research new treatments.

More women are seeing their doctors and undergoing breast cancer screenings, which means that problems can be detected before the cancer spreads. The CDC even offers free or discounted mammograms to underserved women. Thanks to early detection and improved treatments, the survival rate for breast cancer has improved vastly. Mortality rates from breast cancer has dropped an astonishing 39 percent from 1989 to 2015 [source: McGinley].

So who's at risk for breast cancer? And what does someone do once they receive their diagnosis? We'll consider these questions, as well as everything else you want to know about breast cancer, in this article.

What is Breast Cancer?

Breast cancer develops from the uncontrolled growth of abnormal cells in the breast tissue. These growing cells form a tumor in the breast, which can sometimes be felt as a lump. There are several types of breast cancer, but the most common type is ductal carcinoma, which arises in the milk ducts (the passages through which milk flows toward the nipple). A small percentage of breast cancers develop in the lobules (small glands in which milk is produced) and are called lobular carcinoma.

Ductal and lobular cancers are further classified by whether the cancer cells have spread to other parts of the body. If the breast cancer cells are confined within the milk ducts or lobules, it is called noninvasive or in situ cancer. When the cancer has grown into surrounding tissue or spread to other parts of the body, it is called invasive or infiltrating cancer. About 80 percent of all breast cancers are invasive ductal carcinomas (IDC).

Why do these cells start growing abnormally? We'll investigate next.

What Causes Breast Cancer?

The precise cause of breast cancer is unknown; it is most likely due to a combination of genetic and environmental factors. Some women who exhibit many of the risk factors of breast cancer never contract the disease, while some who manifest none of the risk factors may succumb to it.

There does appear to be a link between breast cancer and the hormone estrogen. It's possible that the more that a woman is exposed to estrogen, the greater risk she has of breast cancer at some point. Researchers are investigating events in a woman's life, such as her age of first and last menstruation, her age at childbirth and whether she breastfed or underwent hormone therapy, as these events all affect the estrogen levels in the body.

Researchers have identified two genes that may increase the risk of breast cancer. These genes are called BRCA1 and BRCA2. It's possible to undergo genetic testing to determine if you carry the gene, but doctors warn that the exams can't tell you whether you'll actually get breast cancer. Talk to your doctor if you feel you're at a high risk for breast cancer.

The two most important risk factors to doctors right now are a woman's family history of breast cancer and her age. A woman with a blood relative who had breast cancer is two to three times more likely to develop the disease herself, while women who are older than 60 have a greater risk than younger women [source: WebMD]. But there are other risk factors as well, which we'll talk about next.

What Are the Risk Factors for Breast Cancer?

There are some risk factors for breast cancer that are within your control, while there are others that are out of your hands.

Risk factors include:

Gender: Women are much more susceptible to breast cancer than men.
Age: Older women are at greater risk than younger women.
Family history of breast cancer: If a blood relative, such as a mother or a sister, has had breast cancer, then the likelihood increases that other women in the family will have breast cancer.
Inherited genes: Some women carry the BRCA1 and BRCA2 genes, which increase the risk of breast cancer.
Personal history of breast cancer: If a woman has had breast cancer before, she may have it again in the other breast.
Obesity: Obese and overweight women are at a greater risk of breast cancer.
Alcohol use: Excessive alcohol consumption may increase the risk of breast cancer.
Estrogen-containing medicines: Women who undergo hormone therapy after menopause may have an increased risk of breast cancer, as well as many women who take oral contraceptives containing estrogen. Ask your doctor before beginning any type of medication that includes estrogen.
Age at menstruation, menopause and childbirth: Menstruating at an early age has been linked with an increased risk of breast cancer, as has beginning menopause at an older age. Women who give birth for the first time after the age of 35 may also be more susceptible.

How Is Breast Cancer Detected?

Breast cancer can develop for quite a while without any visible symptoms. As the cancer progresses, these symptoms may become apparent:

A lump or thickening in the breast or under the arm
A change in the size or shape of the breast
Discharge from the nipple or tenderness of the nipple
A change in the color or texture of the skin of the breast or nipple (such as dimpling, puckering, scaliness or new creases)
A scaly, thickened or inward-turning nipple

See your doctor if you experience any of these symptoms. Your doctor may then order a mammogram, or an X-ray of the breast. In the United States, the government recommends that women over the age of 50 get a mammogram every two years; women who exhibit many of the risk factors listed on the last page should consult their doctors about when to start getting regular mammograms. Mammograms are often how doctors detect abnormalities in the breast, though they may also use tools such as breast ultrasound, breast magnetic resonance imaging (MRI) or biopsies.

How Is Breast Cancer Treated?

Breast cancers are divided into different groups, called stages, based on the size of the tumor, whether it is invasive or noninvasive, and whether it has spread through the lymph nodes to other parts of the body. Stage 0 cancer indicates a small, noninvasive tumor, while Stage IV is the highest stage, indicating cancer has spread. To determine whether the cancer is invasive and has spread outside the breast, a surgeon removes one or more lymph nodes and examines them for cancer cells.

The course of treatment depends on the stage of the cancer, the woman's age and her general state of health. Treatment options include:

Lumpectomy, or surgical removal of the tumor
Partial mastectomy, which is removal of the tumor and some surrounding tissue
Total mastectomy, or removal of the entire breast, leaving the underarm lymph nodes
Modified radical mastectomy, which includes removal of the entire breast, some of the underarm lymph nodes and one of the smaller chest muscles
Chemotherapy, which uses drugs to destroy cancerous cells. Chemotherapy may be used before or after surgery.
Radiation uses beams of energy to kill cancerous cells.
Hormonal therapy may be used for certain types of breast cancer that are sensitive to estrogen and progesterone. Tests can determine if the cells will respond to hormones.
Targeted drugs, which include Avastin and Herceptin

After enduring a scary diagnosis and a strenuous treatment, it can be frustrating to learn that you still have to be on guard for a recurrence of the cancer. Still, the odds are with you — 90 percent of women with non-metastatic invasive breast cancer live more than five years after receiving their initial diagnosis, while 84 percent survive more than 10 years. Survival rates depend on many factors, including how early the cancer is diagnosed and whether it stayed just in the breast area or spread [source: CancerNet].

Lots More Information

Sources

Centers for Disease Control and Prevention. "Breast Cancer." (Jan. 10, 2011)http://www.cdc.gov/cancer/breast/index.htm
Mayo Clinic. "Breast Cancer." (Jan 10, 2011)http://www.mayoclinic.com/health/breast-cancer/DS00328
MedlinePlus. "Breast Cancer." (Jan. 10, 2011)http://www.nlm.nih.gov/medlineplus/ency/article/000913.htm
Pink Ribbon International. (Jan. 10, 2011)http://www.pinkribbon.org/Default.aspx
Susan G. Komen for the Cure. "Understanding Breast Cancer Guide." (Jan. 10, 2011)http://ww5.komen.org/understandingbreastcancerguide.html
WebMD. "Breast Cancer Guide." (Jan. 10, 2011)http://www.webmd.com/breast-cancer/guide/default.htm