Prostate Cancer Screening: New Trial Results Spark Debate
Recent findings from the PROBASE trial, presented at the European Association of Urology Congress, are fueling discussion about the potential for a prostate cancer screening program in the UK. The trial compared prostate cancer screening to the established breast cancer screening program, revealing comparable cancer detection rates but also highlighting challenges with false positives.
PROBASE Trial: Key Findings
The PROBASE trial investigated a risk-stratified approach to prostate cancer screening, utilizing both Prostate-Specific Antigen (PSA) testing and Magnetic Resonance Imaging (MRI). According to Prof Sam Hare, CEO of the HLH Imaging Group and Past National Specialty Adviser Imaging (NHS England), the trial “lends further weight behind a risk-stratified, PSA and MRI based approach to screening for prostate cancer, in a study population that is similar to the UK.” The cancer detection rates observed were comparable to those seen in breast cancer screening programs.
However, the trial also revealed a high false positive rate. Prof. Hare suggests that the implementation of Artificial Intelligence (AI) and rigorous quality assurance processes, including radiologist credentialing and “double reading” of scans, could help reduce this rate.
Comparing Prostate and Breast Cancer Screening
The comparison to breast cancer screening has sparked debate. Dr. Alastair Lamb, Clinical Reader at Barts Cancer Institute & Prostate Surgeon at Guys Hospital, points out that breast cancer screening is often considered successful despite its limitations, as breast cancer is typically a symptomatic disease. However, he emphasizes that both prostate and breast cancer often involve the detection of indolent cancers, leading to potential psychological harms and unnecessary treatment. Dr. Lamb also notes that treatments for prostate cancer carry a higher risk of functional side effects – such as bladder, bowel, and erectile dysfunction – compared to breast cancer treatments.
Dr. Lamb stated that the PROBASE trial showed that prostate cancer screening delivers too many false positives.
The Need for Further Evidence
Simon Grieveson, Assistant Director of Research at Prostate Cancer UK, underscored the urgency of addressing prostate cancer, now the most common cancer in the UK. However, he cautioned that more evidence is needed to determine whether a screening program would ultimately save lives without exposing men to unnecessary harm. He noted that direct comparisons to breast cancer screening are tricky due to the long-established nature of the latter.
Grieveson highlighted the ongoing £42m TRANSFORM trial led by Prostate Cancer UK, which aims to provide definitive evidence on the effectiveness of population-wide prostate cancer screening. Prostate Cancer UK is investing in research to determine the best approach to screening.
International Perspectives and Future Directions
Dr. Lennard Lee, Associate Professor at the University of Oxford, highlighted that other countries, such as Germany, are actively generating evidence on modern prostate cancer screening methods. He suggests that risk-adapted screening using PSA followed by MRI can detect clinically significant cancers with performance similar to established breast cancer screening programs. Dr. Lee advocates for piloting modern prostate cancer screening programs in real-world healthcare settings and assessing outcomes regionally, rather than relying solely on lengthy randomized trials.
The UK has not used PSA screening since 1997, but evolving screening technologies and improved management of low-risk cancers through MRI triage and active surveillance are prompting a re-evaluation of this stance.
Conflicts of Interest
Prof Sam Hare disclosed his role as CEO and co-founder of the HLH Imaging Group Limited and his past position as National Specialty Adviser to NHS England for Imaging. Dr Alastair Lamb has received funding from various organizations, including Cancer Research UK, NIHR HTA, and the John Black Charitable Foundation, and has received educational support and consulting fees from several pharmaceutical and medical device companies. Dr Lennard Lee stated his comments were provided in a personal academic capacity.
Abstract: ‘Risk-adapted prostate cancer screening achieves mammography-like benefits – Results from the PROBASE trial’ by Carlsson S et al. Was presented at the European Association of Urology Congress.