Increasing use of radical prostatectomy for lower-risk prostate cancer in Denmark.

Abstract

149 Background: Denmark introduced radical prostatectomy (RP) as the last Nordic country in 1995. Since then, a rapid increment in the Danish incidence of prostate cancer (PCa) is indicative of increasing opportunistic prostate-specific antigen (PSA) testing. We hypothesized that an increasing proportion of men undergo RP for lower-risk PCa. Methods: All patients undergoing RP in Denmark between 1995 and 2011 were included. Changes over time in age at surgery, preoperative PSA, clinical T-category, biopsy Gleason score (GS) are described. Tests for statistically significant changes in trends were performed using linear regression and Cochran-Armitage trend test. Results: Median age at surgery increased from 61.4 to 64.8 (p<0.0001) during the 16 year period. Median preoperative PSA declined from 11.5 to 7.9 ng/ml (p<0.0001). Distribution of biopsy GS changed significantly, especially after 2005. Biopsy GS=7 was found in 20.2% of the patients in 2005 compared to 57.1% in 2011. The proportion of T1 disease increased from 32% to 56%. The proportion of patients above age 65 increased from 26.8% to 48.3% in the 16 year period studied. To adjust for grade, PSA, and age migration, we analyzed changes in the proportion of men age over age 65, with PSA less than or equal to 10 ng/ml, biopsy GS≤3+4, and clinical T1 disease over time. In the 16 year period, this proportion increased from 2% to 16% (p<0-001) of the cohort undergoing RP in Denmark. Conclusions: Significant preoperative age, stage, and Gleason grade migration was found in this complete Danish nation-wide cohort of patients undergoing RP during the past 16 years. This has occurred in the absence of any major changes to the national Danish guidelines for diagnosis and treatment of localized PCa. This effect is likely attributed to an increasing use of PSA although national guidelines recommend against PSA screening. Further, new guidelines from the International Society of Urological Pathology have had a major impact on risk classification. According to recently published randomized trials, the risk of overtreatment of localized PCa with RP is an increasing problem in Denmark.