Clinical study validates that Stockholm3 provides significantly higher clinical benefit than European prostate cancer risk calculator

January 12, 2023

A study comparing Stockholm3 with the Rotterdam Prostate Cancer Risk Calculator (RPCRC) has been published in European Urology Focus (1). RPCRC is a prostate cancer risk calculator that is recommended in the European Association of Urology guidelines. Stockholm3 showed superior performance and a positive clinical benefit whereas the performance of the RPCRC was suboptimal with a considerable underestimation of prostate cancer risk.

The Rotterdam Prostate Cancer Risk Calculator (RPCRC) and Stockholm3 can both be used to aid urologists in their decision to refer men to magnetic resonance imaging (MRI) or biopsy for early detection of prostate cancer. The objective of the study was to assess the external validity of the RPCRC and compare it with using PSA and Stockholm3 to detect clinically significant prostate cancer. Using data from the prospective, population-based, randomized STHLM3-MRI screening trial, 666 participants were included and the probabilities for clinically significant prostate cancer (csPC) were calculated for each participant using the RPCRC and Stockholm3, with and without prostate volume.

Using RPCRC’s recommended risk threshold of ≥4 percent for finding csPC, 54 percent of all csPC cases would be detected versus 94 percent using Stockholm3 with a threshold of ≥11 percent. Calibration of Stockholm3 was adequate while RPCRC underestimated the risk of csPC. The Stockholm3 test showed positive net benefits at clinically relevant thresholds, while the RPCRC showed negative net benefits. Compared with PSA, the RPCRC was associated with lower detection of csPC (84 vs103), while Stockholm3 was associated with higher detection of csPC (143 vs 103).

“This study further validates the clinical benefits of Stockholm3 compared to other methods, and a significant potential to improve prostate cancer diagnostics in Europe by finding more cases early, when the patient can be cured. Including Stockholm3 in both guidelines and clinical practice can save substantial costs and free up resources by reducing overdiagnosis. We are already active in Sweden, Norway, Finland, Germany and Switzerland and will target the rest of Europe in our expansion,” says David Rosén, CEO of A3P Biomedical.

(1) External Validation of the Rotterdam Prostate Cancer Risk Calculator and Comparison with Stockholm3 for Prostate Cancer Diagnosis in a Swedish Population-based Screening Cohort; Palsdottir et al, European Urology Focus 2022.

About A3P Biomedical

A3P Biomedical is a company that specializes in advanced prostate cancer diagnostics. A3P’s main product, Stockholm3, is a clinically and commercially validated blood test for early detection and risk stratification of aggressive prostate cancer. A3P Biomedical is headquartered in Stockholm, Sweden. For more information, please visit www.a3p.com 

About Stockholm3

Stockholm3 is a blood-based test, that runs a combination of protein biomarkers, genetic biomarkers and clinical information through an algorithm to find the probability of clinically significant cancer at biopsy.

Stockholm3 has been evaluated in clinical studies including more than 90,000 men. It is extensively tested in large population-based screening trials, as well as in real world clinical utility studies in primary care, as a reflex test to PSA at values 1.5-20 ng/ml.  Benefits include the ability to reduce unnecessary MRIs, benign and Grade Group 1 prostate biopsies for men with elevated PSA, while simultaneously improving detection of clinically significant cancers in men with low or normal PSA values.  Using Stockholm3 leads to a more accurate risk assessment than the current PSA standard. Stockholm3 detects 40-90% more men with aggressive prostate cancer and, at the same time, reduces over-detection by 40-50% compared to PSA.

Multiple Stockholm3 studies have been published in high-impact journals such as The Lancet Oncology, Journal of Clinical Oncology, and European Urology. The studies address both the specificity and sensitivity of Stockholm3 in multi-ethnic populations as well as health-economic benefits of implementing it in clinical care. For more information about our clinical studies please visit www.a3p.com.

About prostate cancer

Prostate cancer is the most common cancer in men. In 2020, the global incidence of new prostate cancer cases was 1.4 million, and prostate cancer specific mortality 370,000. Global prostate cancer incidence and mortality is expected to rise by 100% and 85% respectively by 2040, driven by an ageing population.

Press contact:
Cecilia Edström
cecilia.edstrom@a3p.com
+46 72 226 2328