KLK3 and prostatitis: First, PSA is a prostate-specific rather than a PCa-specific marker, and some benign prostate diseases may also lead to the abnormal elevation of PSA, such as benign prostate hyperplasia (BPH) and prostatitis.[8] Especially in the range of 4 to 10 ng/mL, there is significant overlap in PSA levels between BPH and PCa patients.