EAU 2017: Controversies: What helps more to characterize the disease? Biomarkers and Genetic Profiling

London, England (UroToday.com) As a response to Dr. Maurer’s presentation advocating for imaging when characterizing prostate cancer at the EAU 2017’s “Prostate Cancer Imaging” session, Dr. Guido Jenster provided the rebuttal making the case for biomarkers and molecular profiling. Dr. Jenster aptly pointed out the limitations of imaging: (i) detection – especially for micro-metastases, (ii) prostate cancer specificity – difficulty distinguishing normal prostate tissue from prostate cancer, (iii) an appreciable false negative rate, particularly for PSMA-PET, and (iv) a false-positive rate, detecting abnormalities not related to prostate cancer.

Dr. Jenster notes that for assessing local invasion for primary disease staging, we currently lack biomarkers beyond usual clinical parameters (ie Gleason score, PSA). For predicting lymph node and distant metastasis, current biomarkers include Oncotype Dx, Prolaris, and ProMark. Although we do not have confirmatory markers in this setting, Dr. Jenster suggests that molecular marker possibilities include OPG, ALP, ICTP and BSP, among others.

For detecting recurrent localized disease and metastasis after primary treatment, current biomarkers include those used in primary staging with the addition of Decipher. Confirmatory markers in this setting are more advanced and include circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA). At the molecular level, we are seeing heterogeneity in these entities based on recent studies in whole genome sequencing of CTCs and targeted sequencing of ctDNA. Indeed, further characterization of the “liquid biopsy” (CTCs or ctDNA) is ongoing.

According to Dr. Jenster, the next generation of molecular characterization will be identifying novel imaging targets from molecular profiles. Potential candidates include ERG inhibitors, TMPRSS2, STEAP, ANPEP, PPAP2A, and novel metabolites. Similar to Dr. Maurer’s conclusion, Dr. Jenster suggests that imaging and biomarkers will likely work in compliment as we attempt to characterize prostate cancer. Continued research in the biomarker field, particular for molecular characterization will be ongoing, challenging and exciting.

Presented by: Guido Jenster, Erasmus MC, Rotterdam, Netherlands

Written by: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto
Twitter: @zklaassen_md

at the #EAU17 -March 24-28, 2017- London, England