AUA 2018: Risk of Men with Intermediate Risk Prostate Cancer Going On To Definitive Treatment During Active Surveillance: Does a High PSA Predict a Worse Outcome?

San Francisco, CA (UroToday.com) Prostate specific antigen (PSA) level is an integral part of prostate cancer risk stratification. However, for patients with otherwise low risk disease characteristics (grade and stage), an elevated PSA (>10 ng/mL) may classify patients at intermediate risk. Whether such rises in PSA portend a worse prognosis is unclear. In a podium presentation at the American Urologic Association Annual Meeting, Dr. Burns and colleagues assess the time to definitive therapy for patients with intermediate risk prostate cancer (defined on the basis of PSA alone), low risk prostate cancer and favourable intermediate risk disease. 



The authors utilized the multi-center, national Center for Prostate Disease Research (CPDR) database to retrospectively analyse outcomes for men treated between 1989 and 2013. They included patients <=75 years with <=cT2a, Gleason score <= 3+4, PSA <20 ng/mL prostate cancer. They restricted this cohort to men who underwent initial active surveillance, defined as no definitive treatment in the first 12 months following diagnosis. They stratified patients into low risk (LR; per NCCN criteria), favourable intermediate risk (FIR; Gleason score <=3+4 and PSA<10), and intermediate risk (IR; NCCN LR but PSA 10-20 ng/mL) groups. The primary outcome was progression to definitive intervention, assessed using Kaplan Meier survival analyses. 

Among 4244 eligible patients, 3005 had LR disease, 902 had FIR disease and 337 had IR disease. Rate of AS differed according to disease characteristics: 16% of patients with LR disease underwent surveillance while 8% of patients with FIR and 11% of patients with IR disease did so. The age at diagnosis was similar between groups. As expected, PSA levels at the time of diagnosis differed: 4.4 ng/mL in LR patients, 5.5 ng/mL in FIR patients, and 13.7 ng/mL in IR patients.  

Among patients who initially started AS, rates of conversion to definitive therapy during follow-up did not significantly differ: 23% among LR patients, 37% among FIR patients, and 25% among IR patients. The median time from initiation of AS to definitive treatment was similar: 20 months for LR, 21 months for FIR and 17 months for IR. 

The authors conclude that, over the study interval, AS is underused in the United States. Patients for whom intermediate risk disease is classified solely on the basis of an elevated PSA are no more likely to transition to definitive intervention than those with low risk or favourable intermediate risk disease. 

Presented By: John Burns 
Co-authors: Lauren Hurwitz, Katherine Levie, Fernando Caumont, Timothy Brand, Inger Rosner, Sean Stroup, Joseph Sterbis, Jennifer Cullen, Christopher Porter 

Written by: Christopher J.D. Wallis, Urology Resident, University of Toronto, Twitter: @WallisCJDat the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA