Screening and Early Detection
Sometimes, cancer can be found before the disease causes symptoms. Checking for cancer (or for conditions that may lead to cancer) in a person who does not have any symptoms of the disease is called screening.
Screening may involve a physical exam, lab tests, and/or procedures to look at internal organs, either directly or indirectly. During a physical exam, the doctor looks for anything unusual and feels for any lumps or growths. Examples of lab tests include blood and urine tests, the Pap test (microscopic examination of cells collected from the cervix), and the fecal occult blood test (to check for hidden blood in stool). Internal organs can be seen directly through a thin lighted tube (such as a sigmoidoscope, which lets the doctor see the rectum and the lower part of the colon) or indirectly with x-ray images (such as mammograms to check the breasts).
Doctors consider many factors before recommending a screening test. They weigh factors related to the individual, the test, and the cancer that the test is intended to detect. For example, doctors take into account the person's age, medical history and general health, family history, and lifestyle. In addition, they assess the accuracy and the risks of the screening test and any followup tests that may be necessary. Doctors also consider the effectiveness and side effects of the treatment that will be needed if cancer is found. People may want to discuss any concerns or questions they have with their doctors, so they can weigh the pros and cons and make an informed decision about whether to have a screening test.
The information contained in these pages
is for educational / reference use only.
Sources:
National Institutes of Health
