PSA

What is Prostate-Specific Antigen (PSA)?

PSA (prostate-specific antigen) is a glycoprotein found in high concentrations in the prostate gland. Normally, protective barriers prevent PSA from entering the bloodstream, but these barriers can be breached by conditions such as cancer, infection, or benign hypertrophy. While PSA can be detected in all males, levels are significantly higher in those with prostate cancer.

Elevated PSA levels are strongly associated with prostate cancer, with more than 80% of men with prostate cancer having levels greater than 4 ng/mL. Higher PSA levels often indicate a larger tumor burden. The PSA test is also useful for monitoring the effectiveness of treatments like surgery, radiation, or hormone therapy, as successful treatment typically results in a marked reduction in PSA levels. Conversely, a significant rise in PSA levels after treatment may indicate a recurrence of prostate cancer.

There is ongoing debate about the value of PSA screening for asymptomatic men. The US Preventive Services Task Force (USPSTF) and other professional organizations have found that annual PSA screening does not significantly reduce prostate cancer mortality. Many experts believe that prostate cancers identified through PSA screening are often not aggressive and do not significantly increase mortality. Additionally, about 80% of PSA screenings result in false positives, leading to unnecessary biopsies and potentially harmful surgeries with minimal benefit. However, annual PSA testing and digital rectal exams (DREs) are recommended for high-risk groups, such as African American men, those with a genetic predisposition (e.g., BRCA mutation), or a strong family history of prostate cancer.

It's important to note that some men with early-stage prostate cancer may not have elevated PSA levels, and not all PSA levels above 4 ng/mL are indicative of cancer. PSA levels can also be slightly elevated in benign conditions such as benign prostatic hypertrophy (BPH) and prostatitis, leading to limited specificity within the diagnostic range of 4 to 10 ng/mL.

Our PSA blood testing kit can help in getting an idea about PSA levels. Results can be shown to your GP to aid in diagnosis. 

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