How Many Men Have False-Positive PSA Tests that Lead to Unnecessary Biopsies?

Beyond Testosterone Book by Nelson Vergel

PSA Screening, Prostate Biopsies, and Prostatitis: Prevalence and Outcomes

Frequency of PSA-Triggered Biopsies (U.S. and Global)

Prostate-specific antigen (PSA) screening became widespread in the 1990s, resulting in a high volume of prostate biopsies.
In the United States, approximately 1 million prostate biopsies were performed annually at the height of PSA screening, with nearly all prompted by elevated PSA levels.
Only about 25% of men who undergo a biopsy for an elevated PSA are found to have prostate cancer, meaning roughly 75% of PSA-triggered biopsies come back negative for cancer.
North America and Europe together account for over 2 million prostate biopsies per year, and worldwide estimates exceed 3 million biopsies annually.
These figures illustrate how common PSA-driven biopsies have been in the general population.

Region	Annual Biopsies	Proportion Positive (Cancer)	Proportion Negative (No Cancer)
United States	~1,000,000	~25%	~75%
USA + Europe	>2,000,000
Worldwide (est.)	>3,000,000

False Positives and Prostatitis as a Cause of Elevated PSA

False-positive PSA tests are very common, leading to many unnecessary biopsies. Clinical trials have shown that about 70–75% of elevated PSA results are false positives (no cancer is found).
One large European study (ERSPC) reported 76% of PSA-positive screenings were false alarms.
False positives are often due to benign conditions like benign prostatic hyperplasia (BPH) or prostatitis (inflammation of the prostate), both of which can raise PSA levels.
Prostatitis is well-documented as a cause of PSA elevation—prostate infections or chronic inflammation can “leak” PSA into the bloodstream and push levels above normal even in the absence of cancer.
Guidelines often recommend ruling out infection/inflammation (e.g., with antibiotic therapy or repeat PSA tests) before proceeding to biopsy.
When men do undergo biopsy for an elevated PSA and no cancer is found, prostatitis is frequently identified as the likely explanation.

Key Study Data:

In a U.S. screening study of 1,851 men (1989–2000), 25% were diagnosed with prostate cancer on first biopsy, while 7% were diagnosed with histological prostatitis (inflammation)—indicating the PSA rise was from prostatitis rather than cancer. Many others had only BPH.
A Turkish study of men with high PSA reported that 28% of all patients biopsied had chronic prostatitis findings (with BPH) on their biopsy, without any cancer. In that series, ~71% of men had no cancer, and within those negatives, nearly 40% had evidence of asymptomatic inflammatory prostatitis.
The large REDUCE trial noted that 77.6% of participants had evidence of prostatic inflammation in biopsy samples, underscoring how common subclinical inflammation is among men undergoing prostate biopsies.
Pathology studies consistently find that prostate inflammation is a frequent histological finding in men with elevated PSA but no cancer. One review found inflammatory cells in around 40–50% of benign prostate biopsy specimens from men screened for high PSA.

Summary Table: Prostatitis Findings in Biopsies

Study/Trial	% with Prostatitis/Inflammation (No Cancer)
U.S. screening study	7% diagnosed with prostatitis
Turkish study	28% chronic prostatitis (with BPH)
REDUCE trial	77.6% with prostatic inflammation
Pathology reviews	40–50% of benign biopsies show inflammation

Historical Screening Trends and Impact

PSA screening led to a surge in biopsies starting in the early 1990s, with prostate cancer diagnosis rates and “false alarms” both spiking.
Around 2012, the U.S. Preventive Services Task Force advised against routine PSA screening, citing overdiagnosis and unnecessary procedures. Biopsy rates dropped significantly (one study showed a ~29% decrease after 2012).
Modern practice often includes repeating PSA tests or using MRI/advanced tests to avoid unwarranted biopsies.
Despite changes, millions of men over the past decades have had PSA-triggered biopsies that turned out benign, with many learning their PSA was elevated due to infection or inflammation, not cancer.

Probability of False-Positive PSA and Unnecessary Biopsy

On any given PSA screening round, about 6–7% of men will have a false-positive PSA that may lead to follow-up procedures.
Over multiple rounds of screening, the probability of a man receiving at least one false-positive result is substantial—one analysis found roughly 20% of men screened underwent an unnecessary biopsy due to a PSA false alarm (number needed to harm = 5).
Early in the PSA era, virtually any confirmed PSA rise >4 ng/mL prompted a biopsy, with cancer detection rates ~20–30% and 70–80% negative biopsies.
Rapid PSA rise often points to prostatitis rather than cancer, leading to strategies like treating with antibiotics and repeating PSA to see if it drops (suggesting an inflammatory cause).

Magnitude and Data Gaps

Magnitude: Both in the U.S. and worldwide, millions of men have undergone prostate biopsies due to elevated PSA, and the majority did not have cancer.
Prostatitis as cause: Among men with negative biopsies, a significant portion have histological prostatitis—e.g., 7% diagnosed outright in one cohort, ~28–40% showing inflammatory tissue changes in others.
Trends: PSA screening has evolved, with more caution and advanced diagnostics reducing unnecessary biopsies, but a large number of men historically underwent biopsies for PSA rises ultimately attributed to prostatitis.
Data gaps: There is no “official” tracking for how many biopsies turned out to be prostatitis. Cancer registries record cancer cases, not benign biopsy findings. Estimates rely on clinical studies and trials.

Consistency of Evidence

All sources consistently show a large proportion of men with elevated PSA do not have cancer, often having benign prostate enlargement or inflammation.
PSA has a high false-positive rate (~65–75%).
Prostatitis is a major confounder in PSA testing, and numerous studies confirm that treating or identifying prostatitis can explain an elevated PSA in many cases.
While exact global totals are not documented, it is estimated that millions of men worldwide have had biopsies for PSA rises ultimately attributed to prostatitis rather than cancer.

In summary, PSA screening has led to a very large number of prostate biopsies, especially in the U.S., and the majority of those biopsies have been negative, with prostatitis being a frequent culprit behind the PSA elevations. Only roughly 1 in 4 biopsies finds cancer, meaning 3 in 4 men had an unnecessary invasive procedure. Among those, prostatitis-induced PSA elevation is common—on the order of tens of percent of cases. This has been a significant issue in prostate cancer screening for decades. Efforts to refine screening (better markers, imaging, etc.) are ongoing to spare men from such unnecessary biopsies. If precise numbers are required, at least hundreds of thousands of men in the U.S. and millions globally over the years have had biopsies for PSA rises ultimately attributed to prostatitis rather than cancer. The evidence is clear that this is a widespread phenomenon, even if exact counts are hard to pinpoint.[/COLOR]

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