Pathologic outcomes in patients with clinically low-risk prostate cancer deemed eligible for active surveillance.

Abstract

110 Background: Active surveillance (AS) is becoming increasingly popular as a treatment option for men with clinically localized low-risk prostate cancer. Gleason score ≤ 6 and clinical stage ≤ T2a are selection criteria for AS. However, Gleason upgrading or upstaging from the diagnostic biopsy to the surgical specimen is not uncommon. We thus sought to identify risk factors that could more accurately predict Gleason upgrading and/or upstaging in AS-eligible men. Methods: 786 patients from our prospective database of 2,412 men who underwent robotic-assisted radical prostatectomy by a single surgeon from January 2005 to August 2010 would have fulfilled standard AS criteria (Gleason sum ≤ 6, clinical stage ≤T2a disease, PSA <10ng/ml, <3 positive cores and ≤50% cancer present in a single core). This formed the basis of our study cohort. Clinicopathologic parameters, including number of cores at initial biopsy, biopsy cancer volume, preoperative PSA, number of cancer-positive cores, body mass index, and prostate volume were recorded prospectively. Data were evaluated using chi- square and multivariate logistic regression analyses. Receiver operator characteristic curves (ROC) were constructed to determine the optimal cutoff values. Results: 320 of 786 AS-eligible patients (40.7%) had Gleason upgrading at final pathology following radical prostatectomy. Upstaging was present in 591 patients (75.1%). 626 patients (79.6%) had Gleason upgrading and/or upstaging. On univariate analysis, BMI, PSA density, preoperative PSA, lower prostate volume and maximum percentage of cancer in biopsy cores were predictors of Gleason upgrading and/or upstaging. On multivariate analysis, all variables, except for BMI and PSA density, lost statistical significance. PSA density > 0.1 ng/ml/cm3 and BMI >29 kg/m2 are the optimal cutoff values based on ROC analysis. Conclusions: PSA density and BMI are significant predictors of Gleason upgrading and/or upstaging, and should be incorporated into contemporary selection criteria for AS protocols. No significant financial relationships to disclose.