test is abbreviated as PSA test and is a measurement
of the serum prostate-specific antigen level. The prostate-specific
antigen test is able to measure the enzyme because normally
leaks into the blood stream in measurable amounts. A
high PSA density or a rising PSA level in the blood
sample may be indicative of prostate cancer which is
associated with higher levels of serum PSA produced
by the enlarged prostate gland.