Public Service Announcement: PSA, or Prostate-Specific Antigen, testing is utilized for screening prostate cancer and monitoring its treatment. PSA is a protein generated by the prostate gland, with most expelled in semen, but a tiny amount enters the bloodstream. The PSA test is conducted on blood samples, requiring a highly sensitive method due to the typically low levels of PSA in the blood. PSA can exist as free PSA or be bound with other blood substances. The total PSA, which is the combination of free and bound PSA, is what the standard PSA test measures.The commonly accepted upper limit for normal PSA levels is 4 ng/mL (nanograms per milliliter). However, since the prostate tends to enlarge and produce more PSA with age, younger men typically have lower levels, while older men have higher levels. Age-specific PSA levels are categorized as follows: 40-49 years (2.5 ng/mL), 50-59 years (3.5 ng/mL), 60-69 years (4.5 ng/mL), and 70-79 years (6.5 ng/mL). The use of age-specific PSA ranges for prostate cancer detection is debated, as not all studies support its superiority over the standard 4 ng/mL threshold.The PSA test serves several purposes in prostate cancer detection: it is a screening tool for undiagnosed individuals, assesses cancer aggressiveness, and monitors the disease in diagnosed patients. As a screening test, an abnormal PSA result often necessitates further testing. PSA levels between 4 and 10 ng/mL are deemed suspicious, though most men with these readings do not have prostate cancer. The likelihood of prostate cancer rises significantly with PSA levels exceeding 10 ng/mL. Regarding aggressiveness, a rapid increase in PSA levels (over 2 ng/mL within a year) before diagnosis correlates with a higher risk of mortality from prostate cancer, despite undergoing prostate removal surgery. For monitoring, an abnormal PSA level post-treatment may suggest cancer recurrence. It's important to note that PSA is not exclusively indicative of prostate cancer; other conditions can elevate PSA levels. Benign prostatic hyperplasia (BPH), which involves prostate enlargement typically due to aging, and prostatitis, an infection of the prostate, are common causes of increased PSA. Other factors like recent ejaculation, urinary procedures, retention, and biopsies can also elevate PSA levels.The PSA test does have limitations. Some prostate cancers do not significantly raise PSA levels, even in advanced stages, and many early-stage cancers don't elevate PSA enough to trigger an abnormal result. Therefore, relying solely on PSA testing is not advisable. A digital rectal exam, a physical examination of the prostate, is a valuable supplementary test.
