The Free Prostatic specific antigen (FPSA) - serum test helps in the screening of prostate cancer. It helps to monitor the ongoing treatment for prostate cancer. It also helps to detect if there is a recurrence of prostate cancer. The Free Prostatic specific antigen (FPSA) test is done: • To screen for prostate cancer • In case of signs and symptoms of prostate cancer • In case of ongoing or post prostate cancer treatment