The Comparison of ISUP Grades Between Prostate Biopsy and Radical Prostatectomy: The Incoherence and Related Factors

Objective: To assess the incoherence rates between prostate biopsies and radical prostatectomy specimens with the use of the International Society of Urological Pathology grading system and to identify the related factors. Materials and Methods: 89 radical prostatectomy patients were analyzed retrospectively. Patients with Gleason score≥6 were included to the study. Patients’ prostate spesific antigen levels, digital rectal examination, prostate biopsy parameters, prostate cancer risk groups and final prostatectomy pathologies were examined. Gleason scores and International Society of Urological Pathology grades of prostate biopsy and prostatectomy specimens were compared. The coherence, upgrading and downgrading rates of pathologies assessed and related factors were identified. Results: Patients’ mean age was 63.1±6.0 years. Prostate spesific antigen levels ranged from 2.8 to 114.0ng/mL(mean:14.8±16.7). The mean number of cores biopsied was 10.9±3.1. Number of patients in low, intermediate and high risk group were 27(30.3%), 34(38.2%) and 28(31.5%) respectively. The coherence, upgrading and downgrading rates according to International Society of Urological Pathology grading were 49.4%, 33.7% and 16.9% respectively. The low risk prostate cancer group showed the most coherent pathologies with the rate of 70.4%(p<0.05, both for International Society of Urological Pathology grading and Gleason scoring). There was no significant relation between prostate spesific antigen level, number of cores biopsied, percentage of cancer involvement, presence of perineural invasion coherence, upgrading and downgrading. Also no significant difference found between coherent, upgrading and downgrading pathologies with respect to the time to radical prostatectomy. Conclusion: The incoherence between prostate biopsy and radical prostatectomy is challenging. Risk of upgrading and downgrading should be considered in decision making. Low risk prostate cancer shows the most coherent pathology between prostate biopsy and radical prostatectomy.