This assay is intended for the quantitative determination of total Prostate-Specific Antigen (tPSA) in human serum and plasma. PSA is a glycoprotein with serine protease activity, primarily inhibited in blood by forming complexes with protease inhibitors like alpha-1-antichymotrypsin and alpha-2-macroglobulin, while 10–30% exists in a free, inactive form. PSA levels can indicate prostate cancer, though many cases—especially in older men—are indolent and asymptomatic. Despite this, PSA screening has been shown to reduce prostate cancer mortality. PSA testing is mainly used to monitor treatment effectiveness in prostate cancer, particularly following radiotherapy, hormone therapy, or prostatectomy. Temporary PSA increases may also occur due to prostate inflammation, trauma, or medical procedures. Low PSA levels can be found in women due to expression in para-urethral and breast tissues.
