Clinical significance and risk factors of International Society of Urological Pathology (ISUP) grade upgrading in prostate cancer patients undergoing robot-assisted radical prostatectomy

Yuta Takeshima,Yuji Hakozaki,Yusuke Sato,Shigenori Kakutani,Yuta Yamada,Yoshiyuki Akiyama,Haruki Kume,Daisuke Yamada,Tetsuya Fujimura,Taro Teshima,Taketo Kawai,Naoki Kimura

doi:10.1186/s12885-021-08248-y

Abstract

BackgroundThe objective of this study is to investigate the clinical significance and risk factors of upgrading in the International Society of Urological Pathology (ISUP) Grade Group System in men undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer.MethodsA total of 583 patients diagnosed with prostate cancer by systematic biopsy were treated with RARP without neoadjuvant therapy from November 2011 to December 2018. Clinicopathological data were obtained from our clinical records. ISUP grade upgrading (IGU) was defined as ‘ISUP grade in prostatectomy specimen determined to be higher than that in the biopsy specimen’. Clinicopathological factors, including age, PSA, prostate volume at biopsy (PV), PSA density, clinical stage, body mass index (BMI), interval from biopsy to prostatectomy, maximum percentage of cancer involvement per core (%CI), total number of biopsy cores, percentage of cancer positive biopsy cores (%PC), and sampling density were analyzed to detect potential risk factors of IGU. Biochemical recurrence (BCR) rates were calculated to analyze the effect of IGU on cancer prognosis.ResultsIn univariate analysis, BMI was a positive predictor of IGU, while %CI, %PC, and sampling density were negative predictors of IGU. BMI and %PC were statistically significant predictors of IGU in multivariate analysis. For cases diagnosed as ISUP grade group 2 or higher at biopsy, there was a significant difference in BCR rates between cases with and without IGU.ConclusionsThe results from our cohort showed that elements of both high-grade cancer risk (such as BMI) and sampling efficiency (such as %PC) contribute to IGU. Excluding cases diagnosed as ISUP grade group 1 at biopsy, BCR-free rates were significantly worse in cases with IGU, highlighting the need for more accurate pathological diagnosis at biopsy.

Highlights

The objective of this study is to investigate the clinical significance and risk factors of upgrading in the International Society of Urological Pathology (ISUP) Grade Group System in men undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer
Since 2014, Gleason score (GS) has been reclassified by the International Society of Urological Pathology (ISUP) into the ISUP Grade Group system [3]
ISUP grade determined by prostate biopsy has assumed even greater importance in recent years with a relative increase in patients undergoing therapy other than radical prostatectomy, namely radiation therapy and active surveillance, where the only tissue analyzed is from the biopsy

Summary

Introduction

The objective of this study is to investigate the clinical significance and risk factors of upgrading in the International Society of Urological Pathology (ISUP) Grade Group System in men undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer. Since 2014, GS has been reclassified by the International Society of Urological Pathology (ISUP) into the ISUP Grade Group system [3]. This new grouping system has been shown to be significant predictors of cancer prognosis such as biochemical recurrence (BCR)-free survival and cancer-specific mortality [4, 5]. The majority of the literature predates the introduction of ISUP grade groups, and updated analysis may be of clinical interest

Objectives

Methods

Results

Discussion

Conclusion