At 14 NHS centers across the United Kingdom, researchers have discovered a blood test that could transform how doctors treat advanced prostate cancer—revealing treatment failure weeks or even months before current methods allow. The finding comes from a study of 117 men with newly diagnosed metastatic prostate cancer, led by Professor Gert Attard of the UCL Cancer Institute and published in Nature Cancer.
The test works by detecting tiny fragments of tumor DNA circulating in the blood. This marks a meaningful shift in precision medicine: while doctors currently rely on measuring PSA (prostate-specific antigen) levels to gauge whether treatment is working, PSA can linger in the blood for months, creating a dangerous lag time. Tumor DNA, by contrast, clears quickly from circulation, acting as an early warning system that cancer is still growing despite ongoing treatment.
The stakes are substantial. About 10,000 men are diagnosed with advanced prostate cancer in the U.K. each year, yet there is currently no reliable way to predict which patients will respond well to hormone therapy alone, and which will need more intensive treatments like chemotherapy. This uncertainty means patients may waste precious months on ineffective treatments while their disease progresses unchecked.
The study's findings are striking. Among men tested 6–12 weeks after starting treatment, three in ten had detectable tumor DNA in their blood. Those men had dramatically lower survival rates: only 50% lived more than two years, compared to 85% of men without detectable tumor DNA. Even more telling, when researchers combined tumor DNA detection with PSA testing, they identified a group of patients who were 20 times more likely to die than men with undetectable tumor DNA and very low PSA levels—a distinction that could trigger a rapid shift to more aggressive treatment strategies.
"By using it alongside PSA blood tests, we can personalize treatments and help find the right balance between reducing side effects and giving men more time with their loved ones," Professor Attard said. The approach represents a fundamental reorientation: instead of waiting months to see whether a treatment is working, clinicians could accelerate treatment decisions in weeks, giving men faster access to therapies more likely to extend both their lifespan and quality of life.
The implications ripple beyond individual patient care. This test could also accelerate the pace of prostate cancer research itself. In clinical trials, researchers could now determine whether new treatments are effective much more rapidly, potentially cutting years off the drug development timeline and getting promising therapies to patients sooner.
Prostate cancer now ranks as the most common cancer in the U.K., with more than 64,000 men diagnosed annually and 12,000 dying from the disease each year. One in eight men will develop it during their lifetime; the risk rises for Black men and those with a family history. Dr. Hayley Luxton, Head of Research Impact & Engagement at Prostate Cancer UK, emphasized the human dimension: "By showing if treatments are effective so much sooner, this test could not only help men with advanced prostate cancer live longer and better but could also massively speed up prostate cancer research in future."
The next phase is crucial. Professor Attard's team is now implementing the test across all their clinical trials for advanced prostate cancer to gather evidence needed for wider rollout. If those results hold, this blood test could soon become standard practice—giving thousands of men each year the information they need to make faster, more informed treatment decisions.