Active surveillance is a decision made by thoughtful people who understand their risk factors and who have accepted uncertainty about whether they should have treatment now or wait for changes from active surveillance first. Active surveillance for prostate cancer involves regular evaluation of the tumor, including PSA tests and digital rectal exams, as well as imaging studies to look for changes in the prostate. Active surveillance may be an option for some men with low-risk prostate cancer. During active surveillance, you and your doctor will regularly check your prostate to look for any signs of cancer progression or an increase in PSA level over time.