The UK Department of Health and Social Care has informed health organizations that General Practitioners will now decide whether to offer symptomatic men over 50 a standard prostate cancer blood test. This shift, reported last week, has drawn sharp criticism, with Prostate Cancer Research stating it is a "shocking betrayal" that could lead to "thousands more men each year to a late and incurable diagnosis."
The controversy highlights ongoing debates about prostate cancer screening and the effectiveness of different testing methods. The standard test offered by the National Health Service (NHS) is the Prostate-Specific Antigen (PSA) blood test, which measures levels of a protein produced by the prostate gland. However, a significant limitation of the PSA test is its inability to reliably differentiate between aggressive and slow-growing prostate cancers, or to determine if a tumor requires immediate treatment. This can lead to over-diagnosis and over-treatment of non-harmful cancers, carrying risks of side effects like incontinence and impotence.
Developed in Sweden in 2011, the Stockholm3 blood test offers a more comprehensive approach. It analyzes PSA levels alongside four other protein markers and 101 genetic markers. These data points, combined with patient information such as age and family history, are processed through an algorithm to generate a risk score for aggressive prostate cancer. The test categorizes results as 'green' for low risk, suggesting re-testing in six years, or 'red' for elevated risk, prompting further investigation such as an MRI scan or biopsy.
Proponents argue that Stockholm3 is more effective at identifying aggressive cancers that require intervention, while also reassuring men with lower risk. "It seems quite powerful at identifying bad cases – where there’s a high risk of an aggressive cancer – and at reassuring men who don’t have a significant problem," said Tim Dudderidge, a consultant urological surgeon at University Hospital Southampton.
A study published in the Annals of Internal Medicine compared the PSA test with Stockholm3 in 12,670 men aged 50 to 74. The research indicated that Stockholm3 was more sensitive in detecting aggressive prostate cancer, achieving a 90% success rate compared to the PSA test's 74%.
The Stockholm3 test has been available privately in the UK for three years at a cost of approximately £395. For men experiencing anxiety about their prostate cancer risk, particularly those told they are not of the age for a standard test, it represents a potential privately funded alternative.
This more advanced testing is also being examined within the large-scale TRANSFORM trial in the UK. This trial is investigating the most accurate and cost-effective methods for prostate cancer screening within the NHS. It involves 16,000 men aged between 45 and 74 undergoing various screening options, including MRI scans, genetic screening, and PSA tests, with blood samples also analyzed by Stockholm3. Initial results from the trial are anticipated in approximately three years. The findings are expected to inform the potential introduction of a wider NHS screening program, which was previously rejected partly due to the perceived unreliability of the PSA test.
Professor Rakesh Heer, a consultant urologist and investigator on the TRANSFORM trial, noted that the PSA test's inability to distinguish between problematic and non-problematic cancers contributes to over-diagnosis. He stated that newer diagnostic blood tests like Stockholm3 are seen as more effective in mitigating this issue. "We want testing to pick up men with the more serious cancers – where we can prevent the cancer growing and spreading," he said.
Dr. Martin Scurr, a GP columnist, has publicly endorsed Stockholm3 for his private patients, citing its improved accuracy over the PSA test and its potential to identify at-risk individuals even with initially low PSA scores.