Most doctors consider prostate-specific antigen levels of up to 4.0 ng/mL in the blood as healthy, states the National Cancer Institute. The PSA test is one of the primary methods that doctors use to check for prostate cancer in men.
A PSA level higher than 4.0 ng/mL indicates that the patient may have prostate cancer, according to the National Cancer Institute. However, prostate cancer can be present in men with any PSA level. A steady increase in PSA level over a period of time is a more tell-tale sign that the patient may have prostate cancer, so doctors often recommend a testing schedule and compare results.