New research from Karolinska Institutet shows that the blood test Stockholm3, together with MRI and targeted prostate biopsies, may lead to a significant decrease in the number of biopsy procedures and diagnoses of harmless disease. The study is published in European Urology.

The results show that the suggested diagnostic strategy decreased the number of biopsy procedures by 38% and the number of men getting a diagnosis with harmless disease by 42%. At the same time, the number of men diagnosed with potentially harmful cancer increased by 10%. The study was performed in collaboration with Swedish (Stockholm) and Norwegian (Oslo, Tönsberg) urology practices and includes 532 men.

"We show that a combination of the Stockholm3 test and targeted prostate biopsies might increase the number of men with potentially dangerous disease that get a diagnosis. At the same time, we can spare many men from unnecessary prostate biopsies. This means that more men get a correct diagnosis and treatment, and that we can decrease unnecessary discomfort and risks," says Tobias Nordström, researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet and urologist at Danderyd Hospital.

Need for improved diagnosis

In the European Union, prostate cancer is the most frequently diagnosed cancer among men, with around 365,000 new cases yearly and 77,000 men dying from prostate cancer. Current practice includes a so-called PSA test and systematic prostate biopsies where 10-12 samples are taken from the prostate. The PSA test has been controversial because it only poorly differentiates between lethal and harmless prostate cancer.

The Stockholm3 test is an alternative test method that combines five biomarkers, over 100 genetic markers, and clinical data, such as age, previous biopsies, and family history of prostate cancer to better assess the risk of potentially harmful prostate cancer.

"The current study confirms our previous findings showing the value of the Stockholm3 test as part of the diagnosis of prostate cancer. Studies of this type have been requested by the National Board of Health and Welfare in Sweden," says Tobias Nordström.