Prevention

Cancer screening: questions worth asking

Screening is done before symptoms and always has potential benefits, limitations and risks.

7 min read · Updated 2026-07-26

Key points

  • Screening is not the same as diagnostic treatment of symptoms.
  • Age, gender, family history and previous findings influence the recommendation.
  • False positives, false negatives and overdiagnosis are possible.

What screening can and cannot do

Screening tries to detect a specific disease before symptoms appear. A good program can reduce mortality from some types of cancer, but no test is perfect.

If you already have a symptom, don't wait for a routine screening. Then a conversation about a diagnostic assessment is needed.

Four useful questions

The decision should take into account individual risk and local programs. Ask a health professional what is recommended in your situation.

  • What is the expected benefit for me?
  • What are the possible harms and false results?
  • What happens if the finding is abnormal?
  • How often and until what age is the test repeated?

Keep previous results

Date, type of test and previous result help to avoid unnecessary repetition. If you have a strong family history of cancer, tell who got it and at what age.

Sources

Cancer Screening OverviewNational Cancer Institute

Screening TestsNational Cancer Institute

This guide provides general information and is not medical advice, a diagnosis or a treatment recommendation. Consult a qualified healthcare professional for decisions about your health.