After radiation therapy, the most widely accepted definition is a PSA that rises from the lowest level (nadir) by 2.0 ng/mL or more. It’s important to try to always use the same lab for all of your PSA tests because PSA values can fluctuate somewhat from lab to lab.
There is no specific normal or abnormal level of PSA in the blood. In the past, PSA levels of 4.0 ng/mL and lower were considered normal. However, some individuals with PSA levels below 4.0 ng/mL have prostate cancer and many with higher PSA levels between 4 and 10 ng/mL do not have prostate cancer . .