58 year-old man present with complain of urinary frequency, hesitancy, or dysuria. A digital rectal examination confirms the presence of a firm, hard, asymmetrical and stony prostate. . As next investigation, PSA levels test was done. All are true about PSA except?

Serum PSA parameters : It is sensitive but not specific Serum PSA -normal : <4ng/ml PSA density : serum PSA / volume PSA volume : PSA velocity of 0.75 ng/mL per year measured at least 3 times over a period of 1.5 to 2 yrs is significant to diagnose Prostate cancer. Free form : for BPH Bound form : for cancer Upper-age-specific reference value of serum PSA : Age Upper age-specific PSA(ng/mL) 40-49 yrs 2.5 50-59 yrs 3.5 60-69 yrs 4.5 70-79 yrs 6.5 PSA is a product of prostatic epithelium and is normally secreted in the semen.