AUA 2017: Older Age at Diagnosis and Disease Volume Predict Upgrading on Confirmatory Biopsy in Prostate Cancer Patients Being Considered for Active Surveillance

Boston, MA ( Prior retrospective studies suggest that age may independently predict risk of Gleason progression on repeat biopsy following a diagnosis of low risk prostate cancer (PCa). It has been shown that older men experience higher rates of PCa-specific mortality; therefore, the appropriateness of active surveillance (AS) may be different in an older patient population. Furthermore, the clinicopathologic features most useful in guiding decisions to re-biopsy remain poorly defined. Dr. Dai presented a study attempting to investigate the risk of Gleason upgrading on repeat biopsy, as well as the features most suggestive of potential Gleason misclassification.

This was a retrospective study analyzing 635 men on AS at a single center between 2002-2015. Within this population, 556 men who were diagnosed with Gleason 3+3 disease on initial biopsy were identified, of whom 406 (73%) received a documented confirmatory biopsy within 1 year of diagnosis. Multivariate logistic regression modeling was performed to determine features associated with detection of Gleason 7 or higher disease on confirmatory biopsy.

85/406 patients (21%) with initial Gleason 6 disease who received a repeat confirmatory biopsy were found to have grade reclassification. On multivariable analysis, older age (per year OR 1.07; 95% CI 1.02-1.11; p = 0.003) and number of positive cores (per core, OR 1.38, 95% CI 1.10-1.73; p = 0.05) were significantly associated with reclassification on confirmatory biopsy. However, initial prostate volume, clinical stage, and PSA were not found to be associated with this risk.

To conclude, older age and the number of positive cores on diagnostic biopsy appear to predict for risk of misclassification of Gleason 7 or greater disease. Therefore, a repeat biopsy is particularly warranted to minimize the risk of diagnostic misclassification.

Presented By: Charles Dai, Cleveland, OH

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA