MRI-first allows men to avoid biopsy for prostate cancer detection

Dr. Charlie Hamm, first author of the study and physician at Charité's Department of Radiology, in front of a magnetic resonance imaging scanner used for the early detection of aggressive prostate cancer. Image credit © Charité | Rafael Poschmann

CANCER DIGEST – Dec. 22, 2024 – A German study has found that 96 percent of men with a normal MRI result would not go on to develop aggressive prostate cancer within three years and that aggressive prostate cancer was detected during further monitoring in just four percent of participants whose initial MRI findings had been negative. The researchers say that the result suggests that invasive biopsy can be safely avoided in these men.

The study led by Charles Hamm, MD of the Charité Universitätsmedizin in Berlin was designed to see if using MRI first in diagnosing prostate cancer was safe over the long term. The results were published in the Dec. 12, 2024 journal JAMA Oncology.

“That means the cancer risk is very low when MRI scans of the prostate do not show any cancer suspicious findings,” said Dr. Hamm in a press release. “Normal MRI findings alone do not offer one hundred percent certainty, but with regular monitoring, potential cancer can still be detected early enough. For many patients, that means they can avoid the discomfort of a biopsy at first and do not need to worry about having cancer that will remain undetected.”

The conventional approach to prostate cancer diagnosis is to test the prostate specific antigen (PSA) levels in the blood. If the level is high enough to suspect cancer, then a needle biopsy is conducted. This is an invasive procedure where 10 to 12 tissue samples are extracted from the prostate by needle and analyzed for cancer by a pathologist. The side effects of needle biopsy include risk of infection, pain and possible over diagnosis of slow growing clinically insignificant cancer, while possibly missing aggressive cancers.

In the study, 593 men treated at private urology practices in and around Berlin underwent multi-parametric MRI. This just means the MRI image was analyzed for multiple parameters specific to prostate cancer. For prostate tissue this includes signal intensity, blood flow, and diffusion of water molecules within the prostate tissue. 

After following the men for eight years, 48 percent of the men had negative MRI results, 86 percent of whom avoided biopsy over 3 years. After 3 years of consistent monitoring, clinically significant prostate cancer was detected in 4 percent of the men with negative MRI results who had aggressive cancer. The results showed that consistent monitoring after a negative MRI over the years was sufficient to catch cancer development at its earliest stage.

“Our results now show that the MRI pathway is safe and effective, including in a decentralized outpatient care network,” Dr. Hamm said. “We hope the study will serve as impetus to further enhance the standing of MRI as an aid to deciding for or against a biopsy in the German guidelines, and elsewhere.” 

Sources: Charité Universitätsmedizin Berlin press release and JAMA Oncology