Timing of Adverse Prostate Cancer Reclassification on First Surveillance Biopsy: Results from the Canary Prostate Cancer Active Surveillance Study

During active surveillance (AS) for localized prostate cancer (PCa), first surveillance biopsy timing varies. We analyzed the Canary Prostate Cancer Active Surveillance Study (PASS), to determine biopsy timing influence on rates of PCa adverse reclassification at first AS biopsy.

Of 1,085 participants in PASS, 421 had <34% cores involved with cancer, Gleason sum ≤6, and thereafter underwent on-study AS biopsy. Reclassification was defined as increase in Gleason sum and/or ≥34% of cores with PCa. First AS biopsy reclassification rates were categorized as <8, 8-13 and >13 months post-diagnosis. Multivariable logistic regression determined association between reclassification and first biopsy timing.

Of 421 men, 89 (21.1%) experienced reclassification at first AS biopsy. Median time from PCa diagnosis to first AS biopsy was 11 months (IQR 7.8-13.8). Reclassification rates at <8, 8-13 and >13 months were 24%, 19%, and 22%, (p=0.65). On multivariable analysis, compared to men biopsied at <8 months the odds ratios (OR) of reclassification at 8-13 and >13 months were 0.88 (95%CI 0.5,1.6) and 0.95 (95% CI 0.5,1.9), respectively. PSA density ≥0.15 (reference <0.15, OR 1.9 [95%CI 1.1, 4.1]) and body mass index (BMI) ≥35 (reference <25 kg/m(2), OR 2.4 [95%CI 1.1,5.7]) were associated with increased odds of reclassification.

Timing of first AS biopsy was not associated with increased adverse reclassification but PSA density and BMI were. In low-risk patients on AS, it may be reasonable to perform first AS biopsy at a later time, reducing overall cost and morbidity of AS.

The Journal of urology. 2016 Oct 31 [Epub ahead of print]

Liam C Macleod, William J Ellis, Lisa F Newcomb, Yingye Zheng, James D Brooks, Peter R Carroll, Martin E Gleave, Raymond S Lance, Peter S Nelson, Ian M Thompson, Andrew A Wagner, John T Wei, Daniel W Lin

University of Washington School of Medicine. Electronic address: ., University of Washington School of Medicine; Fred Hutchinson Cancer Research Center., University of Washington School of Medicine., Fred Hutchinson Cancer Research Center., Stanford University School of Medicine, Department of Urology., University of California San Francisco School of Medicine., University of British Columbia., Eastern Virginia Medical School., University of Texas Health Sciences Center at San Antonio., Beth Deaconess Medical Center., University of Michigan., University of Washington School of Medicine; Fred Hutchinson Cancer Research Center; Seattle Puget Sound Health Care System, Veteran's Affairs Hospital.