In this study, the authors assess the outcomes of prostate biopsies in the period following the original change in PSA screening guidelines by the USPSTF and CTFPHC. This was a retrospective single-institution chart review of all prostate cancer diagnoses by prostate biopsy between 2010 and 2016. Of those patients, 1425 patients were included for analysis (excluded patients known PCa, AS repeat biopsy, TUR prostate biopsy, <10 cores on biopsy, missing PSA data). They then compared patients diagnosed before the recommendations and patients diagnosed after the recommendations, using the October 2011 USPSTF draft date as the cutoff or the October 2014 CTFPHC date as the cutoff. Comparison between patients diagnosed before with those diagnosed after the recommendations’ release date was performed.
Of the 1425 patients, post- USPSTF draft patients (n=347) had higher baseline PSA levels compared to pre-draft patients (n=1078) (median 8.8 ug/L vs. 7.1 ug/L, p <0.001). Post-draft patients were more likely to have higher clinical stage, higher Gleason score, and higher D’Amico intermediate- to high-risk PCa classification.
Of the 1425 patients, post-CTFPHC draft patients (n=977) had higher baseline PSA levels compared to pre-draft patients (n=448) (median 8 ug/L vs.6.4 ug/L, p <0.001) Post-draft patients were more likely to have higher clinical stage, higher Gleason score, and higher D’Amico intermediate- to high-risk PCa classification.
Over the study period, the biopsies rate showed an average decrease of 16.2% per year. While the rate of no cancer and rate of PCa overall decreased during that time frame, the rate of high-risk prostate cancer increased.
Limitations / Discussion Points:
1. Time Lag – while the authors used a strict time point as the cutoff, it will never be known if there is a time lag in practice change. Some of the patients in the second category (“post-recommendations”) may have been screened according to prior guidelines.
2. Uptake of guidelines – while the guidelines were published, it is difficult to truly know if the recommendations were followed by primary care physicians and urologists. Anecdotally, most urologists still recommended PSA screening.
3. In this study, the authors do not assess all prostate biopsies completed before and after the release data; they only look at positive biopsies. In this same time period, the increasing use of MRI may also have accounted for increased identification of higher risk prostate cancer.
In the end, this study has significant limitations, including lack of evaluation of potential confounders (such as mpMRI evaluation, etc). By not assessing all prostate biopsies, and focusing just on positive biopsies, they unfavorably bias their results. While the task force recommendations likely influenced PSA screening in the community to some degree, it is not clear if it can account for all the changes identified in this study.
Presented By: Ahmed S. Zakaria
Co-Authors: Alice Dragomir, Fadi Brimo, Wassim (Wes) Kassouf, Simon Tanguay, Armen Aprikian
Institutions: McGill University
Written By: Thenappan Chandrasekar, MD, Clinical Fellow, University of Toronto Twitter: @tchandra_uromd at the 72nd Canadian Urological Association Annual Meeting - June 24 - 27, 2017 - Toronto, Ontario, Canada