Prostate cancer screening - what's best?

Prostate cancer typically occurs in men over the age of 65, and affects one in 11 men. Exactly why it develops is unknown, but doctors are aware of risk factors that make it more likely - obesity, age and a family history of prostate or breast cancer. Prostate cancer’s diagnosis and treatment are complex topics - and a new study from the UK sheds more light on how you might best navigate these tricky waters.

The researchers invited men between the ages of 50 and 69 who were then split into two groups - half underwent a prostate-specific antigen (or PSA) test - for which a high reading could indicate prostate cancer. In the other group, information about PSA testing was only given to those men who asked for it, and they didn’t necessarily undergo PSA testing. The doctors wanted to see if having a man undergo a single PSA test over the course of his life reduced his risk of death from prostate cancer, compared to the men in the control group who didn’t undergo a PSA test. In all, more than 400,000 men were tracked in this research.

The study found that after following the men for 10 years, more men were diagnosed with cancer in the intervention group (those who got a PSA test), and these men were on average younger at the time they were diagnosed. They also found that the cancers detected in the intervention group were of a lower grade than in the control group. Even so, they found no significant difference in prostate cancer mortality (death) rates between the group who had a single mandatory PSA test over the ten years versus the control group (who may have had a PSA test, but were not forced to).

Implications

There’s debate in prostate cancer research about “overtreatment” - the detection of cancers that may not have been harmful and which, when treated, lead to side effects like impotence or incontinence. This study appears to show there’s little benefit from a single test.  Orther trials have shown some benefits after many years of follow-up but with significant complication rates from treatment . With that said, deciding to screen for prostate cancer is an individual decision which should be undertaken after discussion with your doctor, and it’s something that may be influenced by your personal factors - like your overall health and family history of the disease.

References

Martin, et al. (2018). Effect of a Low-Intensity PSA-Based Screening Intervention on Prostate Cancer Mortality. JAMA doi: 10.1001/jama.2018.0154.