Cancer Risk Factors
Research shows that certain risk factors increase the likelihood that a person will develop cancer. The most common risk factors for cancer include: growing older, tobacco use, sunlight exposure, ionizing radiation, exposure to certain chemicals / substances, some viruses and bacteria, certain hormones, a family history of cancer, alcohol use, poor diet, lack of physical activity, or being overweight.
If you think you may be at risk for cancer, ask your doctor about ways to reduce your risk and set up a regular schedule of monthly or annual checkups as needed.
- Myths & Misconceptions
- Alcohol Use
- Chemical Exposure
- Family History of Cancer
- Growing Older
- Hormones (in certain forms)
- Ionizing Radiation
- Poor Diet & Exercise, Overweight
- Sunlight Exposure
- Tobacco Use
- Viruses and Bacteria
Myths & Misconceptions
- Cancer is not caused by an injury, such as a bump or a bruise.
- Cancer is not contagious. Although being infected with certain viruses or bacteria may increase the risk of some types of cancer, no one can "catch" cancer from another person.
- Having one or more risk factors does not mean that you will get cancer. Most people who have risk factors never develop cancer.
- Some people are more sensitive than others to the known risk factors.
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Alcohol Use
Over the years, a habit of having more than two drinks each day may increase the chance of developing cancers of the mouth, throat, esophagus, larynx, liver, and breast. The risk increases with the amount of alcohol that a person drinks. For most of these cancers, the risk is higher for a drinker who uses tobacco.
Doctors advise people who drink to do so in moderation. Drinking in moderation means no more than one drink per day for women and no more than two drinks per day for men.
If alcohol use is a problem for you or a loved one, Alta Bates Summit offers two substance abuse programs. MPI Chemical Dependency Treatment Program offers services for adults. Thunder Road Adolescent Treatment Center helps adolescents stop the cycle of abuse.
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Chemical Exposure
People who have certain jobs (such as painters, construction workers, artists, housekeepers and those in the chemical industry) have an increased risk of developing cancer because of the chemicals they are exposed to on a daily or weekly basis. The following chemicals have been shown to cause cancer:
Asbestos, Benzene, Benzidine, Cadmium, Nickel, and Vinyl chloride
Decrease Your Risk
1. Always follow instructions and safety tips to avoid or reduce contact with harmful substances both at work and at home.
2. Although the risk is highest for workers with years of exposure, it makes sense to be careful at home when handling pesticides, cleansers, used engine oil, paint, solvents, and other chemicals.
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Family History of Cancer
Most cancers develop because of changes (mutations) in genes. A normal cell may become a cancer cell after a series of gene changes occur. Tobacco use, certain viruses, or other factors in a person's lifestyle or environment can cause such changes in certain types of cells. Some gene changes that increase the risk of cancer are passed from parent to child. These changes are present at birth in all cells of the body. It is uncommon for cancer to run in a family. However, certain types of cancer do occur more often in some families than in the rest of the population. These include: Melanoma, Breast, Ovary, Prostate, and Colon.
Several cases of the same cancer type in a family may be linked to inherited gene changes, which may increase the chance of developing cancers. However, environmental factors may also be involved. Most of the time, multiple cases of cancer in a family are just a matter of chance.
Decrease Your Risk
1. If you think you may have a pattern of a certain type of cancer in your family, you may want to talk to your doctor. Your doctor may suggest ways to try to reduce your risk of cancer. Your doctor also may suggest exams that can detect cancer early.
2. You may want to ask your doctor about genetic testing. These tests can check for certain inherited gene changes that increase the chance of developing cancer. But inheriting a gene change does not mean that you will definitely develop cancer. It means that you have an increased chance of developing the disease.
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Growing Older
The most important, and unpreventable, risk factor for cancer is growing older. Most cancers occur in people over the age of 65, but people of all ages, including children, can get cancer.
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Hormones (in certain forms)
During menopause, doctors may recommend hormones (estrogen alone or estrogen with progestin) to help control problems such as hot flashes, vaginal dryness, and thinning bones. However, studies show that menopausal hormone therapy may cause serious side effects. Hormones may increase the risk of breast cancer, heart attack, stroke, or blood clots. A woman considering menopausal hormone therapy should discuss the possible risks and benefits with her doctor.
Diethylstilbestrol (DES), a form of estrogen, was given to some pregnant women in the United States between about 1940 and 1971. Women who took DES during pregnancy may have a slightly higher risk of developing breast cancer. Their daughters have an increased risk of developing a rare cancer of the vagina and cervix. Women who believe they took DES and daughters who may have been exposed to DES before birth should talk with their doctor about having checkups.
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Ionizing Radiation
Ionizing radiation can cause cell damage that leads to cancer. This kind of radiation comes from rays that enter the Earth's atmosphere from outer space, radioactive fallout, radon gas, x-rays, and other sources.
Radioactive fallout can come from accidents at nuclear power plants or from the production, testing, or use of atomic weapons. People exposed to fallout may have an increased risk of cancer, especially leukemia and cancers of the thyroid, breast, lung, and stomach.
Radon is a radioactive gas that you cannot see, smell, or taste. It forms in soil and rocks. People who work in mines may be exposed to radon. In some parts of the country, radon is found in houses. People exposed to radon are at increased risk of lung cancer.
Medical procedures are a common source of radiation:
The risk of cancer from low-dose x-rays is extremely small. The risk from radiation therapy is slightly higher. For both, the benefit nearly always outweighs the small risk.
Decrease Your Risk
1. Talk with your doctor if you are concerned that you may be at risk for cancer due to radiation.
2. If you live in a part of the country that has radon, test your home for gas levels. The home radon test kit is easy to use, inexpensivest and sold in most hardware stores.
3. Talk with your doctor or dentist about the need for each x-ray they recommend. Ask about shields to protect parts of the body that are not in the picture.
4. Cancer patients may want to talk with their doctor about how radiation treatment could increase their risk of a second cancer later on.
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Poor Diet & Exercise, Overweight
People who have a poor diet, do not have enough physical activity, or are overweight may be at increased risk of several types of cancer. For example, studies suggest that people whose diet is high in fat have an increased risk of Colon, Uterus, and Prostate cancers. Lack of physical activity and being overweight are risk factors for Breast, Colon, Esophagus, Kidney, and Uterus cancers.
Choose a diet rich in fruits and vegetables. Having a healthy diet, being physically active, and maintaining a healthy weight may help reduce cancer risk. Doctors suggest the following:
Decrease Your Risk
1. Eat well: A healthy diet includes plenty of foods that are high in fiber, vitamins, and minerals. This includes whole-grain breads and cereals and 5 to 9 servings of fruits and vegetables every day. Also, a healthy diet means limiting foods high in fat (such as butter, whole milk, fried foods, and red meat).
2. Be active and maintain a healthy weight: Physical activity can help control your weight and reduce body fat. Most scientists agree that it is a good idea for an adult to have moderate physical activity (such as brisk walking) for at least 30 minutes on 5 or more days each week.
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Sunlight Exposure
Ultraviolet (UV) radiation comes from the sun, sunlamps, and tanning booths. It causes early aging of the skin and skin damage that can lead to skin cancer. Doctors encourage people of all ages to limit their time in the sun and to avoid other sources of UV radiation.
Decrease Your Risk
1. Avoid the midday sun (from mid-morning to late afternoon) whenever possible. You also should protect yourself from UV radiation reflected by sand, water, snow, and ice. UV radiation can penetrate light clothing, windshields, and windows.
2. Wear long sleeves, long pants, a hat with a wide brim, and sunglasses with lenses that absorb UV.
3. Use sunscreen everyday. Sunscreen may help prevent skin cancer, especially sunscreen with a sun protection factor (SPF) of 15 or higher. But sunscreens cannot replace avoiding the sun and wearing clothing to protect the skin.
4. Stay away from sunlamps and tanning booths. They are no safer than sunlight. Markstein Cancer Education & Prevention Services provides ongoing skin cancer screening events. Many of these community events are free or low-cost. Call for more information at (510) 869-8833.
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Tobacco Use
Tobacco use is the most preventable cause of death. Each year, more than 180,000 Americans die from cancer related to tobacco use. Using tobacco products or regularly being around tobacco smoke (environmental or second-hand smoke) increases your risk of cancer. People who smoke are more likely than non-smokers to develop the following cancers: Acute Myeloid Leukemia (cancer of the blood), Bladder, Breast, Cervix, Esophagus, Kidney, Larynx (voice box), Lung, Mouth, Pancreas, Stomach, and Throat. People who use smokeless tobacco (snuff or chewing tobacco) are at increased risk of cancer of the mouth.
Quitting is important for anyone who uses tobacco - even people who have used it for many years. The risk of cancer for people who quit is lower than the risk for people who continue to use tobacco. (But the risk of cancer is lowest among those who never used tobacco.)
For people who have already had cancer, quitting may reduce the chance of getting another cancer. There are many resources to help people stop using tobacco.
Decrease Your Risk Markstein Cancer Education & Prevention Services provides an ongoing and frequently updated list of smoking cessation programs to help you quit. Visit the Markstein Cancer Services webpages or call (510) 869-8833 to get their latest list of local resources.
1. Visit the American Lung Association website at www.lungusa.org
2. NCI's Smoking Quitline (1-877-44U-QUIT) and at LiveHelp (click on "Need Help?" at www.cancer.gov) can talk with you about ways to quit smoking and about groups that help smokers who want to quit.
3. www.smokefree.gov has an online guide to quitting smoking and other resources.
4. Doctors and dentists can help their patients find local programs or trained professionals who help people stop using tobacco. Doctors and dentists can suggest medicine or nicotine replacement therapy, such as a patch, gum, lozenge, nasal spray, or inhaler.
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Viruses and Bacteria
Being infected with certain viruses or bacteria may increase the risk of developing cancer.
- Human papillomaviruses (HPVs): HPV infection is the main cause of cervical cancer and may be a risk factor for other types of cancer. The Federal Drug Administration has approved a vaccine for the prevention of cervical cancer. This vaccine is available in most primary care doctor's offices. Alta Bates Summit Medical Center encourages you to discuss this option with your primary care physician.
- Hepatitis B and hepatitis C viruses: Liver cancer can develop after many years of infection with hepatitis B or hepatitis C.
- Human T-cell leukemia/lymphoma virus (HTLV-1): Infection with HTLV-1 increases a person's risk of lymphoma and leukemia.
- Human immunodeficiency virus (HIV): HIV is the virus that causes AIDS. People who have HIV infection are at greater risk of cancer, such as lymphoma and a rare cancer called Kaposi's sarcoma.
- Epstein-Barr virus (EBV): Infection with EBV has been linked to an increased risk of lymphoma.
- Human herpesvirus 8 (HHV8): This virus is a risk factor for Kaposi's sarcoma.
- Helicobacter pylori: This bacterium can cause stomach ulcers. It also can cause stomach cancer and lymphoma in the stomach lining.
Decrease Your Risk
1. The Federal Drug Administration has approved a vaccine for the prevention of cervical cancer. Discuss this preventative treatment option with your primary care physician.
2. Do not have unprotected sex or share needles. You can get an HPV infection by having sex with someone who is infected. You can get hepatitis B, hepatitis C, or HIV infection from having unprotected sex or sharing needles with someone who is infected.
3. You may want to consider getting the vaccine that prevents hepatitis B infection. Health care workers and others who come into contact with other people's blood should ask their doctor about this vaccine.
4. If you think you may be at risk for HIV or hepatitis infection, ask your doctor about being tested. These infections may not cause symptoms, but blood tests can show whether the virus is present. If so, the doctor may suggest treatment. Also, the doctor can tell you how to avoid infecting other people.
5. If you have stomach problems, see a doctor. Infection with H.pylori can be detected and treated.
Webpage information adapted from the NCI Website
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