In Prostate Cancer Screening, a PSA Blood Test Detected About Three Times as Many Cancers as the Digital Rectal Exam

CATEGORY: MEN’S HEALTH

For generations, the “finger exam” has been the image many men associate with checking the prostate. But a large pooled analysis of eight studies covering more than 85,000 men found that a PSA blood test detected roughly three times as many prostate cancers as the digital rectal exam, and adding the exam on top of the blood test did not improve detection.¹

What the Two Tests Actually Are

The prostate is a walnut-sized gland that sits just below the bladder and helps make the fluid in semen. A digital rectal exam, or DRE, is the physical check: a clinician uses a gloved finger to feel the back wall of the prostate through the rectum, searching for lumps or unusual firmness. The PSA test is a blood test that measures prostate-specific antigen — a protein the prostate releases into the blood. Higher levels can be a sign of cancer, but they can also rise for harmless reasons, which is why no single number is a diagnosis on its own.

How the Study Worked

Rather than following one new group of men, researchers combined the results of eight existing studies — three randomized trials and five prospective studies — that together enrolled 85,798 men undergoing prostate screening.¹ For each test they calculated two things a layperson can picture: the cancer detection rate (out of everyone screened, the share in whom a cancer was actually found) and the positive predictive value (among men whose test was abnormal, the share who truly turned out to have cancer). Pooling studies this way reflects how the tests perform on average across many real-world settings.

What They Found

The DRE flagged cancer in about 1% of the men screened, while the PSA test flagged it in about 3% — roughly three times as many. Yet for both tests, only about one in five abnormal results (around 20%) turned out to be cancer, meaning roughly four out of five “positive” findings were false alarms. Notably, pairing the DRE with the PSA test did not detect more cancers than the blood test used on its own.

What This Means for You

A screening result is a prompt for follow-up, not a diagnosis. An abnormal DRE or PSA often traces back to something benign rather than cancer — most commonly an enlarged prostate (a very common change with age) or inflammation of the gland. Because this analysis compares how the tests perform, and because a DRE depends heavily on the individual examiner’s experience, results vary from one setting to the next. Whether to screen at all, when to start, and which test to use are decisions shaped by your age, family history, and personal risk — the kind of conversation worth having with your own doctor.

Key Takeaways

• Across eight studies, a PSA blood test detected about three times as many prostate cancers as the digital rectal exam, and adding the exam did not improve detection.
• For both tests, only about one in five abnormal results was actually cancer; benign conditions like an enlarged or inflamed prostate are common explanations.
• An abnormal result is a reason to follow up, not a diagnosis — the next steps are decided with your clinician.
• If you are weighing prostate cancer screening, the benefits, drawbacks, and timing of PSA testing are worth discussing with your doctor, especially if you have a family history or urinary symptoms.

References

1. Matsukawa A, Yanagisawa T, Bekku K, et al. Comparing the Performance of Digital Rectal Examination and Prostate-specific Antigen as a Screening Test for Prostate Cancer: A Systematic Review and Meta-analysis. European Urology Oncology. 2024;7(4):697–704. link