Screening
Some tests which detect cancer could be called "screening for dysplasia". The principle behind these tests is that physicians expect dysplasia to occur at the same rate in a typical individual as it would in many other people. Because of this, researchers design screening recommendations which assume that if a physician can find no dysplasia at certain time, then doing testing before waiting until new dysplasia could potentially develop would be a waste of medical resources for the patient and the healthcare provider because the chances of detecting anything is extremely low.
Some examples of this in practice are that if a patient whose endoscopy did not detect dysplasia on biopsy during screening for Barrett's esophagus, then research shows that there is little chance of any test detecting dysplasia for that patient within three years.
Individuals at average-risk for colorectal cancer should have another screening after ten years if they get a normal result and after five years if they have only 1-2 adenomatous polyps removed.
Read more about this topic: Dysplasia