what psa level indicates prostate cancer

The PSA (prostate-specific antigen) test is a blood test used to screen for prostate cancer. The PSA level in blood is measured in units called nanograms per milliliter (ng/mL) . While there is no set cutoff point that can tell for sure if a man does or doesn’t have prostate cancer, many doctors use a PSA cutoff point of 4 ng/mL or higher when deciding if a man might need further testing. However, a level below 4 is not a guarantee that a man doesn’t have cancer, and about 15% of men with a PSA below 4 will have prostate cancer if a biopsy is done. Men with a PSA level between 4 and 10 (often called the “borderline range”) have about a 1 in 4 chance of having prostate cancer. If a man’s PSA level is relatively high (approximately 4.0 ng/mL or above), the likelihood of prostate cancer increases. It is important to note that PSA blood levels can fluctuate for many reasons, so further testing will be needed to help find out what is going on if a mans initial blood PSA level is higher than normal.