Under- and upgrading of prostate cancer after radical prostatectomy in a screening setting.

Abstract

105 Background: It has been well established that there is an upward drift in assigned Gleason score (GS) to prostate cancer (PC) biopsies. However, few studies have examined the concordance between biopsy GS and pathological GS after radical prostatectomy (RP) in a screening setting over time. We assessed the proportion of under and upgrading of PC after RP by comparing the prevalence screen with the incidence screens from the European Randomized Study of Screening for Prostate Cancer (ERSPC), section Rotterdam. Methods: From 1993 to 1999, a total of 42.376 men identified from population registries in the Rotterdam region (55-74 yrs) were randomized into a screening or control arm. Men with PSA ≥3.0 ng/ml were recommended for sextant prostate biopsy, which were lateralized since 1996. The screening interval was 4 yrs. Men with screen-detected PC, who underwent RP within 1 yr, were eligible for this study. Results: In all, biopsy and pathological GS were known for 639 men who underwent RP. Of these RPs, 405 were performed between 1994 and 2000 (prevalence screen) whereas 235 cases were performed between 1998 and 2008 (incidence screens). In the prevalence screen, 49.8% of the biopsy GS matched the pathological GS ( Table ). This percentage improved to 58.3% in the incidence screens (p=0.045). The proportion of undergrading after RP was 23.0% in the prevalence screen, which declined to 16.2% in the incidence screens (p=0.049). Upgrading occurred in 27.2% of the cases in the prevalence and 25.5% in the incidence screens (p=0.71). Conclusions: We have demonstrated an improved concordance between biopsy and pathological GS over time by comparing cancers detected in the prevalence screen with those detected in the incidence screens, which is in line with the upward shift of GS classification over time. In addition, significant less undergrading occurred in the incidence screens. However, one should keep in mind that within this screening program still a quarter of the biopsy GS were upgraded after RP in the incidence screens. [Table: see text] [Table: see text]