Study: PCa test identifies tumor aggressiveness

New study data confirm the ability of the ConfirmMDx genes to identify prostate cancer aggressiveness in diagnostic biopsies, researchers reported.

The data, presented at the European Association of Urology, Section of Urological Research meeting in Glasgow, United Kingdom, confirmed that the epigenetic profile of ConfirmMDx genes generated by the test is strongly correlated with established risk stratification metrics, such as Gleason score and the National Comprehensive Cancer Network (NCCN) risk categories, according to a news release from MDxHealth SA, which makes the ConfirmMDx for Prostate Cancer test.

"These data demonstrate that ConfirmMDx for Prostate Cancer not only provides important diagnostic information to help guide the decision on repeat biopsy, but that the genes may also deliver significant prognostic value, potentially determining whether a man has an aggressive or non-aggressive form of prostate cancer," said study co-author Sandra M. Gaston, PhD, of New England Baptist Hospital and Tufts Medical Center, Boston. "This study suggests that the epigenetic markers used in the ConfirmMDx test could have an expanded role in stratifying prostate biopsy patients by providing information that cannot be obtained from the histological examination of the tissue.

The current ConfirmMDx test is “highly sensitive” for DNA hypermethylation of three genes-GSTP1, APC and RASSF1-in the tissue surrounding a prostate cancer, Dr. Gaston said.

“For men who have a histological diagnosis of ‘no cancer,’ a negative result with the current ConfirmMDx test predicts that a subsequent biopsy will also be negative, identifying the majority of men who may avoid repeat biopsy. In this study, we found that hypermethylation of these markers is more intense in the tissue surrounding high-grade prostate cancer, potentially providing additional insights into the clinical significance of a potential undetected prostate cancer on methylation-positive patients,” she said.

In the study, hypermethylation levels of the three ConfirmMDx genes were evaluated on biopsies from 102 men with various Gleason scores (ranging from 3+3 to 4+4) and NCCN risk profiles (ranging from very low to high). All men had undergone a 12-core prostate biopsy under routine clinical practice. No epigenetic aberrations for any of the three genes were found in 20 control patients, who had non-cancer histology in all of their 12-core biopsy specimens.

Specifically, results showed:

For 46 men, the highest observed Gleason score was 6, classifying these men as potential candidates for active surveillance; however, 17% of them exhibited an epigenetic profile that is indicative of higher-grade disease.

Of the nine men with Gleason score 4+3 or higher, 88% had many epigenetic aberrations, in addition to 63% of the men with Gleason score 3+4.

When epigenetic profiling was compared to NCCN risk categories, similar results were obtained, identifying 79% of the men with NCCN intermediate- or high- risk profiles. About one-third of the patients in the very low- and low-risk categories showed similar epigenetic profiles.

One study author is an employee of MDxHealth, Clinical Affairs.