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February 8, 2012

Cancer Risk Factors

Risk factors

Doctors often cannot explain why one person develops cancer and another does not. But research shows that certain risk factors increase the chance that a person will develop cancer. These are the most common risk factors for cancer:

  • Growing older


  • Tobacco


  • Sunlight


  • Ionizing radiation


  • Certain chemicals and other substances


  • Some viruses and bacteria


  • Certain hormones


  • Family history of cancer


  • Alcohol


  • Poor diet, lack of physical activity, or being overweight

Many of these risk factors can be avoided. Others, such as family history, cannot be avoided. People can help protect themselves by staying away from known risk factors whenever possible.

If you think you may be at risk for cancer, you should discuss this concern with your doctor. You may want to ask about reducing your risk and about a schedule for checkups.

Over time, several factors may act together to cause normal cells to become cancerous. When thinking about your risk of getting cancer, these are some things to keep in mind:

  • Not everything causes cancer.


  • Cancer is not caused by an injury, such as a bump or 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.

The sections below have more detailed information about the most common risk factors for cancer. You also may want to read the NCI booklet Cancer and the Environment.




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Cancer Risk Factors

Non-Hodgkin's lymphoma facts

  • NHL is a cancer that originates in the lymphatic system.
  • About 66,000 patients are diagnosed yearly, and approximately 18,000 patients die of NHL yearly in the U.S.
  • There are several subtypes of NHL, each requiring different treatments.
  • Symptoms include swollen lymph nodes, weight loss, fever, and night sweats.
  • NHL is staged on a 1-4 scale with A (no associated symptoms like fever, weight loss, or night sweats) and B subtypes.
  • Staging the cancer is important to determine treatment and predict the outcome of treatment.
  • Depending on the stage and type of NHL, treatment can include chemotherapy, biological therapy, stem cell transplant, and/or radiation therapy.

What is non-Hodgkin's lymphoma?

Non-Hodgkin's lymphoma is a type of cancer that originates in the lymphatic system. It is estimated to be the sixth most common cancer in the Unite...

Read the Non-Hodgkin's Lymphoma article »







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