Trends in histology of newly diagnosed prostate cancer subsequent to USPSTF PSA screening recommendation.

Abstract

68 Background: Reports on impact of the United States Preventive Services Task Force (USPSTF) Grade D recommendation against PSA screening have been short-term and contradictory. We sought to assess whether changes in prostate biopsy (PBx) pathology reporting had occurred in our large urology practices and if such changes persisted over time. Methods: We reviewed prostate histology in the 2 years prior to the USPSTF publication in 2012, and 3 years subsequent to this recommendation. All men (3,429) undergoing PBx in years 2010/11 were combined, creating a baseline against which similar reviews of 2013-August 2015 (2,773, 2,577 and 1,767 patients, respectively) were compared. Analysis of PBx results was the same in all years; we focused only on patients with a cancer diagnosis. Each PBx core was studied for both primary Gleason pattern and score and each patient was assigned a Weighted Gleason Index (WGI) wherein each positive core was multiplied by its own Gleason score, resulting in a single number representing both score and number cores positive. Results: The percent positive PBx increased over time, from the combined rate of 39% (1,338) in 2010/11 to 41.4% (1,147) in 2013, 42.6% (1,097) in 2014 and 46% (813) in 2015 (p<.001). Of 16,271 cores in 2010/11, 5,097 or 31.3% were positive; 14.8% had Gleason 8-10 scores. Of 13,960 cores in 2013, 4,415 or 31.6% were positive; 19.7% had Gleason 8-10 scores. Of 13,577 cores in 2014, 4,694 or 34.6% were positive; 26.1% had Gleason 8-10 scores. Of 10,380 cores in 2015, 3,396 or 32.7% were positive; 25.4% had Gleason 8-10 scores. Gleason 6 scores were stable over time; Gleason 7 scores "lost" 10% over time to higher scores. WGI for 2010/11 was 25.5, compared to 26.0 in 2013 (p=.60), 29.8 in 2014 (p<.001) and 29.2 in 2015 (p=.001). There was no significant difference in WGI from 2014-15. Conclusions: The combined Gleason 6 score stability and decreased biopsies suggest that fewer low risk patients are undergoing PBx- a favorable outcome. However, there has been a persisting increase in both numbers of positive cores as well as cores found with higher Gleason scores. This increases patients presenting with higher risk disease and portends a possible reversal of gains made in reducing prostate cancer mortality.