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Prevention of Cancer


Robert Peter Gale

, MD, PhD, DSC(hc), Imperial College London

Reviewed/Revised Sep 2022

Although there are many different types of cancer, which have different causes and risk factors Risk Factors for Cancer Many genetic and environmental factors increase the risk of developing cancer. However, not all people who are exposed to carcinogens or who have other risk factors develop cancer. (See also... read more , doctors estimate that about 40% of cancers are preventable. Also, individual people have different risks for developing different cancers. Therefore, no set of prevention strategies is effective in every person. However, some general strategies do reduce the risk of cancer or cancer complications in many people. These general strategies fall into 3 categories:

  • Primary prevention: Steps people can take to lessen their chance of developing certain types of cancer

  • Secondary prevention: Directed at people who may already have some kind of cancer but have not developed symptoms

  • Tertiary prevention: Measures aimed at slowing down the effects of a cancer to prevent complications

Screening Screening tests Because many different diseases can cause the same symptoms, it can be challenging for doctors and other primary care practitioners to identify the cause. Doctors first gather basic information... read more is part of secondary prevention of certain cancers. It involves using information about a person, particularly their risk factors for cancer Risk Factors for Cancer Many genetic and environmental factors increase the risk of developing cancer. However, not all people who are exposed to carcinogens or who have other risk factors develop cancer. (See also... read more and results of their physical examination, to guide testing to look for unrecognized cancer. Early detection of cancerous or precancerous growths can save lives. So it is important that people get recommended screening tests for cancer Screening for Cancer Screening tests are used to detect the possibility that a disease is present before symptoms occur. Screening tests usually are not definitive. Results are confirmed or disproved with... read more . For example, Papanicolaou (Pap) tests Screening for Cervical Cancer Sometimes doctors recommend screening tests, which are tests that are done to look for disorders in people who have no symptoms. If women have symptoms related to the reproductive system (gynecologic... read more Screening for Cervical Cancer are a way to screen for cervical cancers Cervical Cancer Cervical cancer develops in the cervix (the lower part of the uterus). Most cervical cancers are caused by human papillomavirus (HPV) infection. Cervical cancer usually results from infection... read more Cervical Cancer by detecting precancerous changes in cells of the cervix. Colonoscopy is one of the screening tests for colorectal cancer Screening tests Family history and some dietary factors (low fiber, high fat) increase a person’s risk of colorectal cancer. Typical symptoms include bleeding during a bowel movement, fatigue, and weakness... read more Screening tests . Removing precancerous colon polyps Polyps of the Colon and Rectum A polyp is a projecting growth of tissue from the wall of a hollow space, such as the intestines. Some polyps are caused by hereditary conditions. Bleeding from the rectum is the most common... read more Polyps of the Colon and Rectum found during screening can decrease the chance of developing colorectal cancer.

Lifestyle factors

  • Decreasing alcohol intake can reduce the risk of head and neck, liver, and esophageal cancer.

  • Decreasing fat intake appears to reduce the risk of breast and colon cancers.

  • Limiting the intake of processed meat and increasing the intake of whole grains and fruits and vegetables may decrease risk of some types of cancer.

The way meat is cooked may also increase the risk of cancer. Grilling, broiling, or frying meats creates certain chemicals that have been linked to colon cancer. Using other cooking methods reduces the formation of these chemicals and may reduce the risk of colon cancer.

Tobacco use is directly associated with one third of all cancers. Not smoking and avoiding exposure to tobacco smoke can greatly reduce the risk of lung, kidney, bladder, head and neck, and several other cancer types. People who quit smoking Smoking Cessation While often very challenging, quitting smoking is one of the most important things smokers can do for their health. Quitting smoking brings immediate health benefits that increase over time... read more can also reduce their risk of cancer, and the risks decrease over time. People who avoid the use of smokeless tobacco (snuff or chew) decrease their risk of cancer of the mouth and tongue. Current smokers or people who have smoked within the past 15 years are candidates for lung cancer screening.

Being overweight or obese increases cancer risk, especially breast cancer, colon cancer, endometrial cancer, esophageal cancer, kidney cancer and pancreatic cancer. People should try to maintain a healthy weight through both diet and exercise. Physical activity itself may reduce the risk of breast, endometrial, and prostate cancers.

Environmental factors

Carcinogens are substances that increase the risk of cancer. Some carcinogens, such as asbestos,benzene, and diesel engine exhaust may be present in the workplace, and workers in industries that use known carcinogens should take appropriate precautions to avoid or minimize exposure. Other carcinogens occur in the home or the environment. For example, radioactive elements that naturally occur in the earth decay into radioactive radon gas, which can collect inside the homes of people living in certain areas. Exposure to radon increases the risk of lung cancer, especially in people who smoke.

Avoiding sun exposure (especially during the middle of the day) can reduce the risk of skin cancers Overview of Skin Cancer Skin cancer is the most common type of cancer. Skin cancer is most common among people who work or play sports outside and among sunbathers. Fair-skinned people are particularly susceptible... read more . Covering exposed skin and using sunscreens with a sun protection factor (SPF) of at least 30 that protect against both ultraviolet A and ultraviolet B light also help reduce the risk of skin cancer.

Vaccines against cancer

Other factors

Aspirin use may reduce the risk of colorectal cancer or result in earlier diagnosis because of bleeding.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Crinone, Endometrin , First - Progesterone MC 10, First - Progesterone MC 5, Prochieve, PROMETRIUM
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