PSA & Prostate Cancer: Why a Simple Blood Test Matters

Prostate cancer touches more lives than most people realize, including some familiar names. President Joe Biden, former UK Prime Minister David Cameron, Robert De Niro, Ben Stiller, John Kerry, Rod Stewart, and Jerry Brown have all faced prostate cancer. Many have gone on to recover, and others continue to manage the disease. Others weren’t as fortunate: French President François Mitterrand, Canadian Prime Minister Pierre Trudeau, musician Frank Zappa, actor Telly Savalas, actor Bill Bixby, and musician Dan Fogelberg all died from the disease, as did O.J. Simpson.

Cameron’s story shows why testing matters. His wife urged him to get checked, and a PSA test led to an MRI and a biopsy that confirmed an early-stage cancer, which was treated successfully. ¹

What is PSA?

PSA, or prostate-specific antigen, is a protein made by both normal and cancerous cells in the prostate gland, and it’s measured with a simple blood test. ² An elevated PSA doesn’t always mean cancer. Non-cancerous conditions such as an enlarged prostate (BPH) or prostatitis can also raise it. ² Still, PSA remains the starting point for screening. The American Urological Association states that when screening for prostate cancer, PSA should be the first test used. ³

When should you start?

Leading medical organizations recommend starting in your 40s or 50s, with earlier testing for men at higher risk:

• The American Urological Association says doctors may offer a baseline PSA test between ages 45 and 50. Testing should begin at 40 to 45 for men at increased risk, including Black men, men with certain inherited gene mutations, and men with a strong family history. ³
  
• The American Cancer Society recommends discussing screening with your provider at age 50 for average-risk men, at 45 for high-risk men, and at 40 for those at even higher risk. ⁴

Both groups emphasize making an informed decision. Screening can catch cancer early, but it can also turn up slow-growing cancers that might never have caused harm. Knowing your number is the first step in that conversation with your doctor. ²

Where free PSA comes in

PSA circulates in the blood in two forms: “free” and bound to proteins. Men with benign prostate conditions tend to have more free PSA, while cancer tends to produce more of the bound form. ⁵ So when total PSA is elevated, especially in the borderline 4–10 ng/mL range, the percentage of free PSA helps suggest whether a benign cause or something more concerning is more likely. A major multicenter study found it can help reduce unnecessary biopsies with very little loss in cancer detection. ⁶ Ordering both together saves a second trip if your total PSA comes back elevated.

If you, or a man you care about, is over 45 and hasn’t checked his PSA recently (or ever), it’s worth walking in for a quick PSA, or a PSA plus free PSA, and checking the results.

Sources

• Express & Star / PA Media, “David Cameron reveals prostate cancer diagnosis and backs screening” (Nov. 2025)
  
• National Cancer Institute, “Prostate-Specific Antigen (PSA) Test,” cancer.gov/types/prostate/psa-fact-sheet
  
• American Urological Association, Early Detection of Prostate Cancer: AUA/SUO Guideline (2023, amended 2025), auanet.org
  
• American Cancer Society, “American Cancer Society Recommendations for Prostate Cancer Early Detection,” cancer.org
  
• National Cancer Institute, NCI Thesaurus, “Percent Free Prostate-Specific Antigen”
  
• Catalona WJ et al., “Use of the percentage of free prostate-specific antigen to enhance differentiation of prostate cancer from benign prostatic disease,” JAMA, 1998