Best abstracts in oncology: A focus on the Stockholm3 test and gut microbiome

Stockholm 3 is a blood-based test that runs a combination of protein and genetic biomarkers, and clinical information through an algorithm to find the probability of clinically significant cancer at biopsy.

During the abstract awarding, Dr. Ugo Giovani Falagario (IT) of the first-prize winning abstract “A0413: Stockholm3 test performance for reducing MRI in Organised Prostate Cancer Testing (OPT)” presented and shared the following conclusions: 

• Integrating the Stockholm3 test as a reflex biomarker with an OPT programme substantially reduces the number of MRI scans and biopsy procedures in the first testing round.
• In this population of 50-year-old men, a higher PSA threshold of 3ng/mL for reflex testing further reduced the number of Stockholm3 tests and MRI cancer cases lost.
• In the current setting, economic neutrality could be achieved by performing reflex testing with the Stockhom3 test at PSA≥3 ng/mL and adjusting the unit price for the test.

Further discussions

According to discussant Prof. Roderick Van Den Bergh (NL) “The perfect diagnostic pathway does not exist but the Stockholm3 test has great potential.” He mentioned various notable studies which demonstrated said potential but with a caveat that results may vary based on the population who had undergone the test, the screening and clinical situation. 

When Stockholm3 was implemented, Prof. Van Den Bergh demonstrated substantial reductions in unnecessary procedures using the data from the abstract. The data showed a 60% decrease in MRIs performed and a 38.5% reduction in biopsies, while still enabling more targeted detection. Overall prostate cancer diagnoses fell by 39%, clinically significant prostate cancer by about 47%, and ISUP GG1 detections by 25%, suggesting improved specificity and a reduction in overdiagnosis.

Are there alternatives to Stockholm3? Prof. Van Den Bergh stated that risk calculators are a solution, especially volume-based risk calculators, which can reduce the number of MRIs performed by 30 to 50%.

“Regarding the balance in diagnostics versus cancer detection, we’re still deciding what role the Stockholm3 will play. There are still questions regarding costs and legislation,” stated Prof. Van Den Bergh.

Access the webcasts of the presentations today via the EAU26 Resource Centre.  For more information about the abstract, you can read it here and watch the abstract presentation here.

The findings of the Second-Prize winning abstract “A0127: Gut microbiome shapes the tumour immune microenvironment and predicts benefit to RC-48 plus tislelizumab in urothelial bladder cancer: A multicentre cohort with translational validation” suggest that the gut microbiome can shape anti-tumour immunity and influence the effectiveness of RC-48 (an antibody–drug conjugate targeting HER2 that has shown promising activity in urothelial bladder cancer [UBC]) plus PD-1 therapy. Microbiome-based patient selection and microbiome modulation may therefore help improve treatment outcomes in UBC. 

A fellow author, Dr. P. Wu, received the award on behalf of Prof. Baisong Cheng (CN).

You can read the abstract here.