Frolic is a playful word with a happy history. It traces back to the Dutch word vroolijk (merry), which in turn evolved from a Middle Dutch combination of vro (happy) and the adjectival suffix -lijc (-ly).
A normal PSA level is considered to be 4.0 ng/mL (nanograms per milliliter of blood). 1  For men in their 50s or younger, a PSA level should be below 2.5 in most cases.  Older men often have slightly higher PSA levels than younger men.
The PSA level also is determined in part by the size and weight of the prostate. The test measures the amount of PSA in the blood in nanograms per milliliter (ng/mL). A PSA of 4 ng/mL or lower is normal; 4â10 ng/mL is slightly elevated; 10â20 is moderately elevated; and 20â35 is highly elevated. Most men with slightly elevated PSA levels do not have prostate cancer, and many men with prostate cancer have normal PSA levels. A highly elevated level may indicate the presence of cancer.