Exploring the use of genomic classifier tests in prostate cancer risk stratification

A systematic review found that while genomic classifier (GC) tests may influence risk classifications or treatment decisions for patients with localized prostate cancer (PCa), there is a need for better data on their cost-effectiveness, clinical utility, and their impact on racial and ethnic groups, particularly Black men. The study is published in Annals of Internal Medicine. 

Prostate cancer is the most common cancer among men, with cases ranging from barely noticeable to highly aggressive ones requiring serious treatment. Determining who needs which type of treatment remains a significant challenge. Traditionally, clinicians rely on tools like the NCCN guidelines, which assess tumor stage, PSA levels, and Gleason grades. However, these tools are not perfect and can sometimes lead to overtreatment or undertreatment. Tests like Decipher by Veracyte, Prolaris by Myriad Genetics, and Oncotype DX Genomic Prostate Score (GPS) by MDx offer a genetic snapshot of tumor aggressiveness, potentially catching things that clinical tools might miss. Despite the potential of these tests, their use in clinical practice is inconsistent due to conflicting guidelines.

Researchers from the Department of Veterans Affairs reviewed 19 studies to assess the impact of these tissue-based genomic tests on risk stratification and treatment decisions for localized prostate cancer. The researchers analyzed test type, quality, population characteristics, risk reclassification and recommended and/or received treatment intensity and found that in low risk of bias observational studies, most patients with low or very low baseline risk did not see an increase in risk classification after GC testing. This pattern differed across GC test types, however, with GPS-based studies finding 0% - 11.9% of patients were reclassified to a higher risk category versus Decipher-based studies finding 12.8% to 17.1% reclassified to a higher risk category. In a randomized trial, reclassification to higher risk was more prevalent than in the observational studies examined. Observational studies indicated that GC testing often led to more patients opting for conservative management options like active surveillance.

The researchers note that the differences in results from observational and randomized trials emphasize the need for well-designed trials evaluating the impact of GC tests in management of PCa to inform patient-clinician decision-making.