Researchers begin to unravel why some prostate tumours can be seen with magnetic resonance imaging and others go undetected

Determining whether a patient with prostate cancer requires aggressive therapy or active surveillance is a growing challenge for the healthcare system. Blood tests can detect early signs of prostate cancer, but these tests can lead to many unnecessary and painful biopsies for patients whose disease never becomes aggressive.

Multi-parametric magnetic resonance imaging (mpMRI), a type of non-invasive imaging technique, has the potential to help determine which patients require biopsies and which can be spared possible negative side effects, such as bleeding, pain and infection. Some tumours are visible by mpMRI while some are not, yet it’s not well understood if this visibility can predict a tumour’s aggressiveness.

Researchers at OICR have teamed up with clinicians from the University of California, Los Angeles to investigate the molecular properties of MRI-visible and MRI-invisible tumours. In their recent study, published in European Urology, they found that visible tumours have similar features to aggressive tumours and discovered new features that may be contributing to the disease’s aggression. 

“Even if two tumours are similar in size and in similar positions, one still may be MRI-visible and one may be MRI-invisible,” says Kathleen Houlahan, PhD Candidate at OICR and lead author of the study. “We wanted to see if this visibility could help us determine if a cancer is aggressive, so we took the first step towards unraveling the relationship between a patient’s MRI results and the molecular characteristics of their tumour.”

Recent commentary on the study highlights Houlahan’s work as an “initial foray” into the intersection of radiology, pathology and genomics, but recognizes the limited size of her exploratory study. Recent MRI-focused clinical trials will provide larger datasets for further investigation.

 “If we can better understand why some tumours show and some don’t, we could potentially use imaging to predict the course that a patient’s disease will take,” says Houlahan. “Ultimately, we hope that this technique can help reduce unnecessary prostate biopsies and ensure that the men who need treatment get the treatment they need.”