Outcome of repeated prostatic biopsy during active surveillance: implications for focal therapy

Abstract

Active surveillance (AS) is commonly recommended for men with localized low-intermediate-risk prostate cancer (PCa). The aim of our study was to assess the probability that patients with PCa would develop unfavorable disease features (UDF) while under AS for the purpose of evaluating whether immediate hemiablation therapy (HAT) could bring clinical benefit to selected patients. In our cohort of AS patients, 157 were diagnosed with unilateral PCa. Using five different definitions of UDF, patients' data were used to simulate the theoretical outcome whether these patients were managed by immediate unilateral HAT or remained on AS. The mean age at the time of diagnosis was 67 years (range 47-81). The median follow-up was 5.4 years [interquartile range (IQR) 3.4-8]. Baseline characteristics included a median PSA value of 5.5 ng/ml (IQR 4.5-7), median number of biopsy taken of 10 (IQR 6-10), and maximum cancer percentage on any core of 10 (IQR 5-20). Of the 157 patients, 144 (92 %) had a Gleason score (GS) of ≤6. Using the whole range of definition for UDF, 10-47 % of patients developed UDF while under AS. Using baseline GS, maximum percentage of cancer on any core, and PSA density, we found significant trends for higher development of UDF for patients under AS. The majority of our patients did not develop UDF while under AS. Our study, thus, suggests that careful patient selection for focal therapy should be performed to avoid subjecting patients to unnecessary treatment.