Improving detection and reducing overtreatment

Prostate cancer is the most common cancer among men in Sweden, with about 10,000 new cases diagnosed annually. Despite advancements in diagnostics and treatments, managing prostate cancer remains challenging due to its often silent progression and the complexities surrounding early detection.

The Prostate-Specific Antigen (PSA) test, while widely used, has limitations in distinguishing between aggressive and indolent cancers and benign conditions, leading to potential overdiagnosis and overtreatment.

In his thesis, Lars Björnebo, MD and Ph.D. student at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, investigated and compared new tools for prostate cancer detection, such as MRI-based diagnostics and the Stockholm3 test, potentially offering hope for more accurate diagnoses. However, ensuring access to these innovations and balancing timely intervention with avoiding unnecessary treatments remains a critical challenge in improving patient outcomes.

What are the most important results in your thesis?

We confirmed that incorporating MRI in active surveillance protocols is justified since it is significantly associated with adverse pathology after having undergone surgery to remove prostate cancer. We also found that long-term use of 5-ARIs, drugs used for benign prostate enlargement, is safe concerning the risk of prostate cancer and may reduce the risk of dying from prostate cancer.

Comparing MRI with the Stockholm3 test showed that both methods are effective in detecting clinically significant cancers, but detection with MRI reduces unnecessary biopsies and diagnoses of indolent cancers. Lastly, using PSA density (PSA divided by prostate volume) before deciding on MRI could reduce the number of MRIs needed while still catching most significant cancers, though using a high PSA density cutoff level would miss many. These findings suggest that better-targeted use of diagnostics can improve prostate cancer care while reducing unnecessary procedures.

Why did you become interested in this topic?

Back in medical school, I worked as an assistant nurse in the urology ward at Capio Saint Göran’s Hospital and that’s where my interest in prostate cancer took off. I met men who had undergone radical prostatectomies. While they were generally doing well after surgery, many were only in their 50s and 60s and worried about side effects like incontinence and erectile dysfunction.

Seeing their concerns firsthand, I decided to focus my first project on active surveillance—basically delaying treatment to spare men from those side effects. After that, it felt natural to dive into the diagnostic side, figuring out how to avoid detecting indolent cancers that are better left alone and monitored through active surveillance. I’m thrilled to see our research directly helping men like those I met at the urology ward a few years back.

What do you think should be done in future research?

Even though we’ve made a lot of progress in prostate cancer diagnostics, there’s still plenty of work to do to bring research into clinical practice and update guidelines. The guidelines are changing rapidly, making it tough for primary care providers to stay fully updated. I believe education—for both health care providers and patients—will be incredibly important going forward.

A lot of the current discussion revolves around screening for prostate cancer. It has the potential to be optimized to better select which men should undergo further investigation, but needs to be set up very carefully, considering all its implications and the resources required for large-scale screening.