Abstract
Gleason grading is the best independent predictor for prostate cancer (PCa) progression. Recently, a new PCa grading system has been introduced by the International Society of Urological Pathology (ISUP) and is recommended by the World Health Organization (WHO). Following studies observed more accurate and simplified grade stratification of the new system. Aim of this study was to compare the prognostic value of the new grade groups compared to the former Gleason Grading and to determine whether re-definition of Gleason Pattern 4 might reduce upgrading from prostate biopsy to radical prostatectomy (RP) specimen. A cohort of men undergoing RP from 2002 to 2015 at the Hospital of Goeppingen (Goeppingen, Germany) was used for this study. In total, 339 pre-operative prostatic biopsies and corresponding RP specimens, as well as additional 203 RP specimens were re-reviewed for Grade Groups according to the ISUP. Biochemical recurrence-free survival (BFS) after surgery was used as endpoint to analyze prognostic significance. Other clinicopathological data included TNM-stage and pre-operative PSA level. Kaplan–Meier analysis revealed risk stratification of patients based on both former Gleason Grading and ISUP Grade Groups, and was statistically significant using the log-rank test (p < 0.001). Both grading systems significantly correlated with TNM-stage and pre-operative PSA level (p < 0.001). Higher tumor grade in RP specimen compared to corresponding pre-operative biopsy was observed in 44 and 34.5% of cases considering former Gleason Grading and ISUP Grade Groups, respectively. Both, former Gleason Grading and ISUP Grade Groups predict survival when applied on tumors in prostatic biopsies as well as RP specimens. This is the first validation study on a large representative German community-based cohort to compare the former Gleason Grading with the recently introduced ISUP Grade Groups. Our data indicate that the ISUP Grade Groups do not improve predictive value of PCa grading and might be less sensitive in deciphering tumors with 3 + 4 and 4 + 3 pattern on RP specimen. However, the Grade Group system results less frequently in an upgrading from biopsy to the corresponding RP specimens, indicating a lower risk to miss potentially aggressive tumors not represented on biopsies.
Highlights
Prostate cancer (PCa) is the most common cancer type among men worldwide accounting for more than 20% of all newly diagnosed cancers [1]
In radical prostatectomy (RP) specimens, we observed lower frequency of biochemical recurrence (BR) in Grade Group 4 tumors (42.9%) compared to Grade Group 3 tumors (53.7%), but clearly higher and lower rate compared to Grade Group 2 (23.1%) and Grade Group 5 (71.9) tumors, respectively (Table 2)
5-year-Biochemical recurrence-free survival (BFS) rate of International Society of Urological Pathology (ISUP) Grade Group 2 (74.2%) and ISUP Grade Group 3 (41%) tumors at RP were higher compared to tumors graded with former Gleason Score 3 + 4 (48.3%) and 4 + 3 (37.2%)
Summary
Prostate cancer (PCa) is the most common cancer type among men worldwide accounting for more than 20% of all newly diagnosed cancers [1]. Patients show a highly variable course of disease, resulting in a major challenge for clinical management [2]. It is of utmost importance to stratify patients with early-stage disease into certain risk groups, predicting the probability of remaining an indolent or progressing to an aggressive form of PCa. In addition to clinical stage and serum PSA level, Gleason grading of the tumor is a powerful prognostic marker at time point of diagnosis and has major impact on therapy decision [3]. A limitation of Gleason grading is upgrading from biopsy to radical prostatectomy (RP) specimens, most often in lower grade tumors, which is associated with worse outcome of patients [4]. Considerable interobserver variability limits PCa grading to be reproducible in a subset of cases [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
