The Importance of Regular Prostate Screening Prostate cancer is the most common cancer diagnosis in men today. One in six men in their lifetime will be diagnosed with prostate cancer. The best method of early detection is screening. Talk to your doctor about prostate cancer screening--that includes a rectal exam where we feel the prostate through the rectum, and a PSA or a prostate-specific antigen blood test. There are a lot of reasons why a man might have an elevated PSA and cancer is just one of them. We use the PSA test to figure out what a person's risk is for prostate cancer.