Collaboration for Academic Primary Care (APEx) Blog
Collaboration for Academic Primary Care (APEx) Blog
Posted by ma403
15 May 2024Authors: Tanimola Martins and Liz Down
One of the beauties of traveling on UK motorways is the ability to make pit stops at service stations, where you can take care of necessities like using the restroom, grabbing a bite to eat, squeezing in some exercise, or even jotting down a blog post. Probably not in that exact sequence. Speaking of restrooms at these stops, they are no longer just convenient places for your private moments, as my son would put it. Nowadays, they also serve as platforms for advertising, showcasing everything from insurance schemes (dodgy at times) to health promotion campaigns, especially relating to cancer awareness. Prostate cancer tends to be the most featured, but other sites are catching up – see Figure 1. The message is often along the lines of “… 1 in 8 men will get prostate cancer in their lifetime.” And as a Black person, I am acutely aware that both the risk of having and dying from the disease are higher for me as I approach the magic age of 50. What many of these awareness campaigns don’t say is the fact that most prostate cancers are indolent and perhaps they need not worry too much about them anyway
In this population-based study, our interest lay in understanding the mechanism underlying the excess risk of death from prostate cancer among Black men, particularly concerning the role of the prostate-specific antigen (PSA) test. This test is one of the primary diagnostic tools employed by general practitioners when evaluating men with suspected prostate cancer symptoms in primary care settings. Clinical guidelines for interpreting PSA test results in UK primary care typically consider the patient’s age but not ethnicity. However, our previous systematic review, which primarily encompassed studies conducted in the US, demonstrated considerable variability in PSA values by ethnicity, with Black men exhibiting higher baseline PSA values than men of other ethnicities. In this study, our aim was to ascertain whether similar trends are observed among UK Black men and to evaluate the impact of these trends on prostate cancer diagnosis.
The study used routinely gathered primary care data from Clinical Practice Research Datalink, including 730515 men who had a PSA test between 2010 and 2017. Statistical analysis was used to investigate prostate cancer incidence in men with a raised PSA result in the year following a test.
The results showed that Black men were most likely to receive a prostate cancer diagnosis in the year following a raised PSA result, at 25% of those included. In comparison, 20% of White men and 13% of Asian men with a raised PSA were diagnosed with prostate cancer. When we looked at cancer stage, we found that the rate of prostate cancer diagnosed at an advanced stage after a raised PSA result was similar for White and Black men, at 7.5% and 7.0% respectively. Only 4.5% of Asian men were diagnosed with advanced prostate cancer within a year of a raised PSA result.
What this study suggests is that higher baseline PSA values in Black men may contribute to the diagnosis of potentially slow-growing tumours, which may not pose a significant threat to these men during their lifetime. This raises the question of the potential harm of overdiagnosis among Black men, a topic not explored in this study and thus representing our next line of inquiry
Acknowledgement: This project was funded by Cancer Research UK and the NIHR School for Primary Care Research, with additional support from the Higgins family.
References
Elizabeth Down, Melissa Barlow, Sarah Bailey, Luke Mounce, Samuel Merriel, Jessica Watson, Tanimola Martins (2024). “Association between patient ethnicity and prostate cancer diagnosis following a prostate-specific antigen test: a cohort study of 730,000 men in primary care in the UK.” BMC Medicine 22(1): 82.