Should You Be Screened for Cancer? The Benefits and Risks

Should you be tested for cancer? Maybe not, says H. Gilbert Welch, M.D., author of the same titled book. Welch is one of a growing group of health professionals urging individuals to make thoughtful decisions about cancer screenings. He says one way to become sick is to start looking for something to be wrong.

Testing for Cancer

Screening is the process of looking for cancer in people who have no symptoms. Individuals who have symptoms or suspicious screening results may have additional diagnostic screening tests. Mammograms, for example, can be both screening and diagnostic.

Physicians, cancer advocacy groups, and patient survivors repeatedly deliver the message that detecting cancer early through screening tests is critical to saving lives. Many people have benefitted from cancer screening when they find potentially dangerous cancers during the window of opportunity when treatment is most likely to be successful. During a colonoscopy, for example, physicians can remove polyps before they have a chance to become cancerous.

However, Welch says, "most people who are tested will never get cancer, [so] most people cannot benefit from testing. And others will die from cancer despite our best efforts to find cancers early. In fact, screening tests tend to miss the fastest-growing and most deadly cancers."

Screening tests themselves may actually increase risk or cause harm. Take mammograms. Radiation to the breast is a risk factor for breast cancer, especially in younger women, and it's cumulative over time.

Screening tests miss some cancers (false negatives) and also uncover abnormalities that are actually benign. These false positives can trigger a cascade of additional tests, unnecessary treatment (with accompanying side effects), and immeasurable stress and anxiety. For example, treatment for slow-growing prostate cancer, which might not ever cause symptoms, can have serious side effects, such as impaired sexual performance and trouble controlling urination and bowel movements.

In an article published in Journal of the National Cancer Institute the author wrote, "It seems clear that we have done an inadequate job of educating screening candidates about the harms and benefits of cancer screening, including the extent to which screening can reduce cancer mortality."

Be an informed healthcare consumer. Learn all the facts about cancer screening tests you're considering. Recognize what tests can-and cannot-do, and understand the potential outcomes if you are tested. While cancer screening undoubtedly saves some lives, Welch and his like-minded peers encourage you to make individual screening decisions, in collaboration with your physician, that are right for you based on your age, risk factors, and personal tolerance for uncertainty.




Welch, Gilbert H. Should You be tested for cancer? Maybe not and here's why. Berkeley and Los Angeles, California, University of California Press, 2004.

Stefanek, Michael Edward, "Uninformed Compliance or Informed Choice? A Needed Shift in Our Approach to Cancer Screening." Journal of the National Cancer Institute. Web. 21 November 2011.

American Cancer Society. Testing for Prostate Cancer. Web. 2010.

National Cancer Institute. "Genetic Testing for Breast and Ovarian Cancer Risk: It's Your Choice." Web. 20 March 2006.