Research in cancer prevention
We already know a lot about how to prevent cancer. If we, as a society, put everything we know into practice through healthy lifestyle choices and policies that protect the public, we could prevent about 4 in 10 cancer cases. But we still need to learn more about how the disease develops and how we can stop it before it starts.
It can take years of studying large groups of people to understand what factors prevent or lower our risk of developing cancer. Researchers often find it useful to study groups of people who have a higher than average risk of developing certain types of cancer to find the best ways to try to prevent it. Their risk may be high because they have a precancerous condition or family history of cancer or because they smoke. Researchers are also trying to find out how to prevent cancer from coming back in people who have been treated for the disease.
Research in cancer prevention includes the following areas.
Environment and workplace
Any substance that is known to cause cancer is called a carcinogen. Research has identified a number of carcinogens that you may be exposed to at work, at home or in the environment, such as asbestos, arsenic and radon. More research is looking at other possible carcinogens to help us understand what is and isn’t linked to cancer. This helps us avoid exposure to possible carcinogens in the environment, at home or at work by limiting their use or using them safely.
Research has shown that a diet high in vegetables and fruit may help prevent cancer. Research has also shown that a diet high in red meat or processed meat increases the risk of colorectal cancer. The exact relationship between what you eat and cancer needs more study, but there is scientific proof that some food groups, individual foods and specific substances in foods can lower the risk of developing cancer.
The exact relationship between physical activity and cancer needs more study, but there is scientific evidence linking being active with a lower risk of developing cancer. We still need to learn more about what types of physical activity are best for reducing cancer risk.
Sedentary behaviour refers to activities that need very little physical movement and don’t use much energy, such as sitting at a desk or lying down for long periods of time. Sedentary behaviour is different from not getting enough physical activity.
Research shows there is a link between sitting too much and a higher risk of cancer. But more study is needed to understand how sedentary behaviour is linked to specific cancers and to find helpful ways to move more and sit less.
Vaccines and biologicals to prevent cancer
Researchers continue to study vaccines that may help prevent cancer. We already know from research that human papillomavirus (HPV) vaccines help protect against cervical cancer and other cancers linked to HPV including vaginal, vulvar, anal, oral and oropharyngeal cancers. Researchers are trying to make HPV vaccines that help protect against more types of HPV. They are also studying how vaccinating against other viruses, such as hepatitis B, or treating others, such as hepatitis C, could also help prevent cancer.
They are also trying to develop vaccines that protect against colorectal cancer in people with Lynch syndrome and vaccines to protect against breast cancer in women who carry the BRCA gene mutation. Vaccines are also being developed to help prevent pancreatic cancer and lung cancer by targeting specific gene mutations linked to these cancers.
Taking certain drugs, vitamins or other substances may help prevent cancer from developing or prevent it from coming back. This area of study is called chemoprevention. Chemoprevention is being studied in people with an average risk of cancer, but researchers mostly focus on how to prevent cancer in people who have a higher than average risk of developing the disease.
Many studies show a link between vitamin D and cancer risk. There is growing scientific evidence that vitamin D may lower the risk of some types of cancer. The evidence that vitamin D lowers cancer risk is strongest for colorectal cancer, but we need more research to know for sure.
Other vitamins and supplements
Researchers are trying to find out if taking certain vitamins or supplements can help prevent cancer. They include the following:
- vitamin A (including retinoids and carotenoids)
- vitamin E
- folic acid and other B vitamins
We need more research to find out if vitamins or supplements can prevent certain types of cancer.
Statins are drugs used to lower your cholesterol level. They do this by blocking an enzyme that the body needs to make cholesterol. Lowering cholesterol levels can help treat and prevent heart disease. Researchers are trying to find out if statins also help reduce the risk of certain types of cancer.
Research has shown that statins may block cell functions involved in how cancer develops, grows and spreads. To know for sure if taking statins can prevent certain types of cancer, we need more research.
Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs)
NSAIDs are used for pain, such as headaches or backaches. They may also be used for more severe pain in chronic conditions like arthritis or sciatica. Common NSAIDs include acetylsalicylic acid (ASA, Aspirin), ibuprofen (Advil, Motrin) and celecoxib (Celebrex). NSAIDs lessen inflammation and stop prostaglandins from being made by the body. Prostaglandins control cell growth, cell death and the development of blood vessels.
Research shows that people who take NSAIDs have a lower risk of developing colorectal cancer. Research also shows that taking NSAIDs seems to help lower the risk of developing esophageal, stomach and other types of cancer. But we need more research to better understand the role NSAIDs may play in preventing cancer. Currently, NSAIDs are not recommended as a way to prevent cancer.
Metformin (Glucophage) is a drug used to treat diabetes. Metformin works by lowering glucose levels in the blood. People who have diabetes have a higher than average risk of developing cancer. Studies show that metformin may lower the risk of some types of cancer in people with diabetes. Researchers are trying to find out if metformin can lower the risk of cancer in people who have a high risk of developing the disease.
Using cancer treatment drugs to prevent cancer
Researchers are trying to find out if drugs that treat cancer can help prevent it. Researchers study which genes are changed or mutated in people who have precancerous conditions that can lead to cancer if they’re not treated. Then they try to treat the precancerous conditions – and prevent cancer – with the same drugs that are used to treat people with cancer who have these same gene changes or mutations.
Looking at how a person’s genes can be used to help prevent, diagnose and treat cancer is called personalized medicine.
Other areas of cancer prevention research
Other areas of research in cancer prevention include:
- trying to find out how socioeconomic status (a person’s economic and social position compared to others including income, education and type of work), a person’s biological and genetic makeup and other factors can cause higher rates of cancer in certain populations
- developing better programs, policies and interventions to protect the public from cancer-causing substances
- trying to find and test new ways of preventing cancer in people who have a higher than average risk of developing the disease, such as people who have certain gene mutations
- developing new and better ways to find and treat precancerous conditions so they don’t develop into cancer
Having the potential to develop into cancer.
A precancerous condition can (or is likely to) become cancerous (malignant).
Also called premalignant.
An inherited condition that causes a large number of polyps to develop in the lining of the colon and rectum but not as many polyps as are found in familial adenomatous polyps (FAP).
There are 2 types of Lynch syndrome. Type A increases the risk for colorectal cancer, and type B increases the risk of several cancers, including colorectal cancer and other digestive system cancers, and ovarian and uterine cancers in women.
Also called hereditary non-polyposis colorectal cancer (HNPCC).
Making progress in the cancer fight
The 5-year cancer survival rate has increased from 25% in the 1940s to 60% today.