Is small prostate volume a predictor of Gleason score upgrading after radical prostatectomy?

The factors impacting on Gleason score upgrading in prostate cancer with initial low Gleason scores

BACKGROUND

This study aims to investigate the factors contributing to the discrepancy in between biopsy Gleason score (GS) and radical prostatectomy GS in patients diagnosed with prostate cancer.

METHODS

341 patients who underwent radical prostatectomy from 2011/04 to 2020/12 were identified. 102 Patients with initial GS of six after biopsy were enrolled. Preoperative clinical variables and pathological variables were also obtained and assessed. The optimal cut-off points for significant continuous variables were identified by the area under the receiver operating characteristic curve.

RESULTS

Upgrading was observed in 63 patients and non-upgrading in 39 patients. In the multiple variables assessed, smaller prostate volume (PV) (p value = 0.0007), prostate specific antigen density (PSAD) (p value = 0.0055), positive surgical margins (p value = 0.0062) and pathological perineural invasion (p value = 0.0038) were significant predictors of GS upgrading. To further explore preclinical variables, a cut-off value for PV (≤ 38 ml, p value = 0.0017) and PSAD (≥ 0.26 ng/ml2, p value = 0.0013) were identified to be associated with GS upgrading.

CONCLUSIONS

Smaller PV and elevated PSAD are associated with increased risk of GS upgrading, whereas lead-time bias is not. A cut-off value of PV < 38 ml and PSAD > 0.26 ng/ml2 were further identified to be associated with pathological GS upgrading.

Compatibility of the radical prostatectomy specimen findings with digital rectal examination

PURPOSE

The purpose of this research is to evaluate the compatibility of the pathological grading of prostate carcinoma in transrectal biopsy sample (TRUS), Gleason scores 3 + 3 = 6, and a palpable nodule in digital rectal examination (DRE) with radical prostatectomy samples in patients with prostate cancer.

METHODS

Sixty-one patients with prostate cancer were included. Transrectal biopsy of the prostate and Gleason score were recorded in the histopathological report of the radical prostatectomy sample independently for each patient.

RESULTS

The mean ± standard deviation of PSA level in patients was 8.52 ± 2.23. The average prostate volume was 46.0 ± 12.17 ml. The average density of PSA was 20.06 ± 7.74 ml. The results revealed that 36% of the people after surgery had similar pathology compared to the score before surgery (Gleason score 3 + 3 = 6) while 64% had non-homogeneous reporting (Gleason score 3 + 4 = 7 and other results). The study showed that low prostate volume before surgery was associated with a higher Gleason score after surgery. Although there was no significant relationship between PSA level above 10 before surgery and higher Gleason scores after surgery, there was a statistically significant relationship between PSA density above 15% and higher Gleason scores after surgery (P < 0.001). PSA density was a strong predictor for postoperative Gleason score (P = 0.004).

CONCLUSION

The high level of PSA density before surgery increased the risk of higher Gleason scores after surgery by 95.99%. Over 64% of the individuals had inconsistency in tumor upgrading, and the palpable firm nodule in the DRE should not be ignored.

Role of inflammatory factors in prediction of Gleason score and its upgrading in localized prostate cancer patients after radical prostatectomy

Purpose

To investigate the role of inflammatory factors including systemic immune-inflammation index (SII) and neutrophil to lymphocyte ratio (NLR) in predicting Gleason Score (GS) and Gleason Score upgrading (GSU) in localized prostate cancer (PCa) after radical prostatectomy (RP).

Methods

The data of 297 patients who underwent prostate biopsy and RP in our center from January 2014 to March 2020 were retrospectively analyzed. Preoperative clinical characteristics including age, values of tPSA, total prostate volume (TPV), f/t PSA ratio, body mass index (BMI), biopsy GS and inflammatory factors including SII, NLR, lymphocyte to monocyte (LMR), neutrophil ratio (NR), platelet to lymphocyte ratio (PLR), lymphocyte ratio (LR), mean platelet volume (MPV) and red cell distribution (RDW) as well as pathological T (pT) stage were collected and compared according to the grades of RP GS (GS ≤ 6 and GS≥7), respectively. ROC curve analysis was used to confirm the discriminative ability of inflammatory factors including SII, NLR and their combination with tPSA for predicting GS and GSU. By using univariate and multivariate logistic regression analysis, the association between significant inflammatory markers and grades of GS were evaluated.

Results

Patients enrolled were divided into low (GS ≤ 6) and high (GS≥7) groups by the grades of GS. The median values of clinical factors were 66.08 ± 6.04 years for age, 36.62 ± 23.15 mL for TPV, 26.16 ± 33.59 ng/mL for tPSA and 0.15 ± 0.25 for f/t PSA ratio, 22.34 ± 3.14 kg/m² for BMI, 15 (5.1%) were pT1, 116 (39.1%) were pT2 and 166 (55.9%) were pT3. According to the student's t test, patients in high GS group had a greater proportion of patients with pT3 (P<0.001), and higher NLR (P=0.04), SII (P=0.037) and tPSA (P=0.015) compared with low GS group, the distribution of age, TPV, f/t PSA ratio, BMI, LMR, NR, PLR, LR, MPV and RDW did not show any significantly statistical differences. The AUC for SII, NLR and tPSA was 0.732 (P=0.007), 0.649 (P=0.045) and 0.711 (P=0.015), with threshold values of 51l.08, 2.3 and 10.31ng/mL, respectively. According to the multivariable logistic regression models, NLR ≥ 2.3 (OR, 2.463; 95% CI, 0.679-10.469, P=0.042), SII ≥ 511.08 (OR, 3.519; 95% CI 0.891-12.488; P=0.003) and tPSA ≥ 10.31 ng/mL (OR, 4.146; 95% CI, 1.12-15.35; P=0.033) were all independent risk factors associated with higher GS. The AUC for combination of SII, NLR with tPSA was 0.758 (P=0.003) and 0.756 (P=0.003), respectively. GSU was observed in a total of 48 patients with GS ≤ 6 (55.17%). Then patients were divided into 2 groups (high and low) according to the threshold value of SII, NLR, tPSA, SII+tPSA and NLR+tPSA, respectively, when the GSU rates were compared with regard to these factors, GSU rate in high level group was significantly higher than that in low level group, P=0.001, 0.044, 0.017, <0.001 and <0.001, respectively.

Conclusion

High SII, NLR and tPSA were associated with higher GS and higher GSU rate. SII was likely to be a more favorable biomarker for it had the largest AUC area compared with tPSA and NLR; the combination of SII or NLR with tPSA had greater values for predicting GS and GSU compared with NLR, SII or tPSA alone, since the AUC area of combination was much higher. SII, NLR were all useful inflammatory biomarkers for predicting GS and detecting GSU among localized PCa patients with biopsy GS ≤ 6.

Analysis of risk factors for Gleason score upgrading after radical prostatectomy in a Chinese cohort

Background

To study the risk factors of Gleason score upgrading (GSU) after radical prostatectomy (RP) in a Chinese cohort.

Methods

The data of 637 patients who underwent prostate biopsy and RP in our hospital from January 2014 to January 2021 were retrospectively analyzed. The age, body mass index (BMI), prostate‐specific antigen (PSA) level, testosterone (TT) level, neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR), eosinophil‐to‐lymphocyte ratio (ELR), aspartate aminotransferase/alanine transaminase (AST/ALT) ratio, clinical stage, the biopsy method, and pathological characteristics of specimens after biopsy and RP were collected for all patients. Univariate analysis and multivariate logistic regression analysis were used to analyze the risk factors of GSU after RP. The predictive efficacy was verified with the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. We performed the analysis separately in the overall cohort and in the cohort with Gleason score (GS) = 6.

Results

In the overall cohort, 177 patients (27.79%) had GSU, and in the GS = 6 cohort, 68 patients (60.18%) had GSU. Multivariate logistic regression analysis showed that in the overall cohort, clinical stage ≥T2c (OR = 3.201, p < 0.001), the number of positive cores ≥3 (OR = 0.435, p = 0.04), and positive rate of biopsy (OR = 0.990, p = 0.016) can affect whether GS is upgraded, and the AUC of the combination of the three indicators for predicting the occurrence of GSU was 0.627. In the GS = 6 cohort, multivariate logistic regression analysis showed that clinical stage ≥T2c (OR = 4.690, p = 0.001) was a risk factor for GSU, and the AUC predicted to occur GSU is 0.675.

Conclusion

Clinical stage ≥T2c, the number of positive cores <3, and lower positive rate of biopsy are the risk factors of GSU. This study may provide some references for clinicians to judge the accuracy of biopsy pathological grading and formulate treatment strategies, but the specific effect still needs clinical practice certification.

Histopathological Ratios to Predict Gleason Score Agreement between Biopsy and Radical Prostatectomy

Biopsy proven Gleason score is essential to decide treatment modalities for prostate cancer, either surgical (radical prostatectomy) or non-surgical (active surveillance, watchful waiting, radiation therapy and hormone therapy). Several studies indicated that biopsy proven Gleason score may underestimate Gleason score at radical prostatectomy, hence we aimed to calculate the minimum length of biopsy cores needed to have Gleason score agreement. We evaluated 115 prostate cancer patients who underwent multiparametric magnetic resonance/transperineal ultrasonography fusion biopsy and subsequently, radical prostatectomy. Biopsy proven Gleason score was consistent with Gleason score at subsequent radical prostatectomy in 82.6% of patients, while in 17.4% of patients, Gleason score was higher at radical prostatectomy. Gleason score agreement showed a strong direct association with a ratio > 0.05 between the total volume of biopsies performed in tumor area and the volume of the corresponding tumor at radical prostatectomy. A significant association was also found with a ratio ≥ 0.0034 between the tumor volume in the biopsy and the volume of the corresponding tumor at radical prostatectomy and with a ratio ≥ 0.086 between the tumor volume in the biopsy and the total volume of biopsies performed in the tumor area. These results could be exploited to calculate the minimum length of biopsy cores needed to have a correct Gleason score estimation and therefore be used in fusion targeted biopsies with volume adjustments.

How can we predict the active surveillance candidates meeting all Epstein criteria prior to prostate biopsy to avoid overdiagnosis?

OBJECTIVE

To investigate the effectiveness of PSA, prostate volume (PV) and free-to-total PSA ratio (fPSA%) in predicting patients meeting all active surveillance criteria, including Epstein criteria.

METHOD

Retrospective analysis was made of the data of 1901 men who underwent transrectal ultrasound (TRUS)-guided prostate biopsy in our clinic between January 2015 and December 2019. The active surveillance criteria were determined as Gleason score ≤6, when specified ≤2 positive cores with <50% cancer involvement in every positive core, a clinical T1c, a PSA <10ng/mL and a PSA density <0.15 ng/mL/cc. Patients who met all active surveillance criteria were included in Group 1, and other patients with prostate cancer were included in Group 2.

RESULTS

The study included 336 patients with available data of age, total-free PSA levels, PV calculated by TRUS. Group 1 consisted of 82 patients and Group 2 consisted of 254 patients. PV and fPSA% were significantly higher and PSA was significantly lower in Group 1 than in Group 2. On multivariate analysis, the independent predictors were determined to be PSA and PV while fPSA% was not.

CONCLUSION

By using PSA and PV in predicting patients meeting all active surveillance criteria, unnecessary biopsies and ultimately overdiagnosis can be reduced.

Are TRUS-guided prostate biopsies in clinical practice robust enough to make a correct assessment of the surgical strategy in prostatectomies? Poor correlation between preoperative prostate biopsies and postoperative specimens

Objective: TRUS-guided prostatic biopsies are the mainstay procedure to diagnose prostatic cancer. The aim was to investigate how accurate and reliable these biopsies are by comparing them with the final pathology results after prostatectomy.Materials and methods: One hundred consecutive patients diagnosed with localized prostatic cancer using this technique and who subsequently underwent a radical prostatectomy in Västerbotten County were included in this study. From the pathological-anatomical diagnosis (PAD) of core needle biopsies, data was extracted on the location of the tumour within the prostate, the tumour volume and the Gleason score, and compared with the characteristics of the prostatectomy specimen. The frequency and type of deviation between the pre-operative and post-operative examinations was recorded.Results: In 95% of the cases there was a poor correlation between the pre-operative and post-operative pathological reports. In the final report, 48% had a higher Gleason score and 88% had deviations in localization when compared with the information from the biopsies. If known prior to surgery, a total of 104 of these deviations might have had a significant impact on the surgical strategy.Conclusions: The pre-operative biopsies in this setting rarely match the final prostate PAD results (5%). The most common deviations were in localization and in Gleason score, where the majority consisted of a higher Gleason score and/or tumour presence in a previously unknown location. This information, if known prior to surgery, might have altered the treatment strategy and ultimately the outcome of the treatment.

Risk of upgrading from prostate biopsy to radical prostatectomy pathology: Is magnetic resonance imaging-guided biopsy more accurate?

Background: This study compared magnetic resonance imaging-guided biopsy (MRI-GB) and transrectal ultrasound guided biopsy (TRUS-GB) with the final histology of the radical prostatectomy (RP) specimen.

Methods: Our subjects were 229 patients with prostate cancer (PCa), proven histopathologically using MRI-GB or TRUS-GB, who underwent RP at our center between December 2015 and December 2016. The main group included 92 patients who underwent MRI-GB and the control group included 137 patients who underwent 12-core TRUS-GB. Histological findings for RP specimens were compared with those from biopsies. We also evaluated predictors of upgraded Gleason score (GS), using uni- and multivariate analyses.

Results: Upgraded GS between biopsy and RP specimen occurred to 22.7% (52/229) of the cohort overall. In univariate analysis, prostate-specific antigen density (PSAD) (P<0.001), prostate volume (PV) < 30 ml (P<0.001), biopsy modality (P=0.027), biopsy GS (P=0.032) and measured MRI lymph node metastasis (P=0.018) were prognostic factors. Multivariate logistic regression analysis showed PV < 30 ml (P<0.001) and biopsy modality (P=0.001) were independent predictors of upgraded GS.

Conclusions: MRI-GB may enhance the diagnostic accuracy of prostate cancer detection in final histopathology with lower rate of upgraded GS than TRUS-GB. Also, PV < 30 ml and biopsy modality were independent predictors of upgraded GS.

Nomograms for predicting Gleason upgrading in a contemporary Chinese cohort receiving radical prostatectomy after extended prostate biopsy: development and internal validation

The current strategy for the histological assessment of prostate cancer (PCa) is mainly based on the Gleason score (GS). However, 30-40% of patients who undergo radical prostatectomy (RP) are misclassified at biopsy pathologically. Thus, we developed and validated nomograms for the prediction of Gleason score upgrading (GSU) in patients who underwent radical prostatectomy after extended prostate biopsy in a Chinese population. This retrospective study included a total of 411 patients who underwent radical prostatectomy at our institute after having prostate biopsies between 2011 and 2015. The final pathologic GS was upgraded in 151 (36.74%) of the cases in all patients and 92 (60.13%) cases in men with GS=6. In multivariate analyses, the primary biopsy GS, secondary biopsy GS and obesity were predictive of GSU in the patient cohort assessed. In patients with GS=6, the significant predictors of GSU included the body mass index (BMI), prostate-specific antigen density(PSAD) and percentage of positive cores. The area under the curve (AUC) of the prediction models was 0.753 for the entire patient population and 0.727 for the patients with GS=6. Both nomograms were well calibrated, and decision curve analysis demonstrated a high net benefit across a wide range of threshold probabilities. This study may be relevant for improved risk assessment and clinical decision-making in PCa patients.

Comparative rates of upstaging and upgrading in Caucasian and Korean prostate cancer patients eligible for active surveillance

Purpose

To investigate the impact of race on the risk of pathological upgrading and upstaging at radical prostatectomy (RP) in an Asian (Korean) and Western (Caucasian) cohort eligible for active surveillance (AS).

Materials and methods

We performed a retrospective cohort study of 854 patients eligible for AS who underwent RP in United States (n = 261) and Korea (n = 593) between 2006 and 2015. After adjusting for age, PSA level, and prostate volume, we utilized multivariate logistic regression analysis to assess the effect of race on upgrading or upstaging.

Results

There were significant differences between Caucasian and Korean patients in terms of age at surgery (60.2 yr. vs. 64.1 yr.), PSA density (0.115 ng/mL/mL vs. 0.165 ng/mL/mL) and mean number of positive cores (3.5 vs. 2.4), but not in preoperative PSA values (5.11 ng/mL vs. 5.05 ng/mL). The rate of upstaging from cT1 or cT2 to pT3 or higher was not significantly different between the two cohorts (8.8% vs. 11.0%, P = 0.341). However, there were higher rates of upgrading to high-grade cancer (Gleason 4+3 or higher) in Korean patients (9.1%) when compared to Caucasian counterparts (2.7%) (P = 0.003). Multivariate logistic regression analysis showed that age (OR 1.07, P < 0.001) and smaller prostate volume (OR 0.97, P < 0.001), but not race, were significantly associated with upstaging or upgrading.

Conclusions

There were no differences in rates of upgrading or upstaging between Caucasian and Korean men eligible for active surveillance.

Developing a Correct System to Evaluate the Accuracy of Gleason Score in Prostate Cancer of Chinese Population

INTRODUCTION

A study was conducted to develop a new correct system to improve the overall rate of Gleason sum concordance between biopsy and final pathology.

MATERIALS AND METHODS

A total of 592 consecutive patients who had undergone transrectal ultrasound-guided prostate biopsy and radical prostatectomy were evaluated during the first stage. Age, PSA, PSA density (PSAD), biopsy cores, positive cores, prostate volume, positive core rate (PCR), core volume rate (CVR) and digital rectal examination findings were considered predictive factors. A multiple logistic regression analysis involving a backward elimination selection procedure and linear regression analysis involving a stepwise procedure were applied to select independent predictors.

RESULTS

Positive cores, PCR, CVR and PSAD were included in our assessing credibility model in the first stage. A significantly higher area under the receiver-operating curve was obtained in our model compared with CVR alone (0.641 vs. 0.517). In the second stage, patients with credibility of pre-operative Gleason score <0.388 were subjected to further evaluation. Compared with the 2 statuses, the rate of overall concordance was significantly increased (60.3 vs. 50.2%, p = 0.002).

CONCLUSIONS

We developed a follow-up strategy based on the new and correct system, which represents an important consideration procedure when clinicians make decisions with regard to treatment plans.

Accuracy of MRI-Targeted in-Bore Prostate Biopsy According to the Gleason Score with Postprostatectomy Histopathologic Control--a Targeted Biopsy-Only Strategy with Limited Number of Cores

RATIONALE AND OBJECTIVES

Accuracy of ultrasound-guided biopsy and Gleason score is limited, and diagnosis of insignificant cancer with Gleason score ≤6 is frequent when extended biopsy schemes are used. We evaluated whether the magnetic resonance imaging (MRI)-targeted in-bore prostate biopsy correctly identifies the Gleason score of prostate cancer in histopathologic correlation after prostatectomy. Simultaneously a targeted concept is expected to keep down the rate of insignificant cancer.

MATERIALS AND METHODS

We compared retrospectively the Gleason score of the MRI-targeted in-bore biopsy with prostatectomy specimens in 50 men with prostate cancer. Endorectal MRI included T2-weighted imaging, diffusion-weighted imaging, dynamic contrast-enhanced imaging, and spectroscopy. Lesions with a prostate imaging-reporting and data system (PI-RADS) score ≥3 were considered. Upgrading and downgrading of tumors was evaluated, and significant upgrading was defined as a shift in Gleason score from 6 to 7 or more.

RESULTS

Gleason score was concordant in 66% of the patients, overall upgraded in 30% of patients, and downgraded in 4% of patients. Significant upgrading of the Gleason score from 6 to 7 occurred in eight patients; upgrading did not exceed one step in the Gleason score. After prostatectomy the Gleason score 6 was found in 20% of patients. The median number of cores obtained was 4 (range 2-6), and the median number of positive cores was 2 (range 1-4).

CONCLUSIONS

In-bore MRI-targeted biopsy offers good accuracy in the Gleason score with postprostatectomy histopathologic control when compared to the literature. A limited number of cores are sufficient to achieve these results. The fraction of insignificant cancer identified by targeted only-biopsy is low. Upgrading is restricted to one step in the Gleason score. Clinicians should be aware of positive findings in MRI and the biopsy technique used when assessing prostate biopsy results.

Validation of active surveillance criteria for pathologically insignificant prostate cancer in Asian men

OBJECTIVES

To validate the ability of contemporary active surveillance protocols to predict pathologically insignificant prostate cancer among Asian men undergoing radical prostatectomy.

METHODS

We retrospectively reviewed data on 132 patients eligible for any active surveillance criteria out of 450 patients that underwent radical prostatectomy at several institutions between 2006 and 2013. We validated the ability of seven contemporary active surveillance protocols to predict pathologically insignificant prostate cancer. Traditional and updated criteria to define pathologically insignificant prostate cancer were used. Predictive factors for pathologically insignificant prostate cancer were determined by logistic regression analysis.

RESULTS

The predictive rate for updated pathologically insignificant prostate cancer of respective active surveillance criteria was 51% for Johns Hopkins Medical Institution, 41% for Prostate Cancer Research International: Active Surveillance Study, 39% for University of Miami, 32% for University of California, San Francisco, 32% for Memorial Sloan-Kettering Cancer Center, 31% for Kakehi and 27% for University of Toronto. Predictive rates for pathologically insignificant prostate cancer in Asian men were far lower than in USA men. On multivariate analysis, predictive factors of updated pathologically insignificant cancer was prostate volume (odds ratio 1.07, P = 0.004). By adding prostate volume to Prostate Cancer Research International: Active Surveillance Study criteria, the predictive rate for updated insignificant prostate cancer was improved up to 66.7%.

CONCLUSIONS

Active surveillance can be carried out considering the clinical characteristics of prostate cancers depending on ethnicity, as current active surveillance criteria seem to have a lower predictive ability value of insignificant prostate cancer in Asian men compared with men in Western countries.

Accuracy of prostate measurements on MRI with and without an endorectal coil

PURPOSE

To assess accuracy of prostate measurements with and without endorectal coil (ERC).

MATERIALS AND METHODS

Anteroposterior (AP), transverse (TX) and craniocaudal (CC) measurements were recorded from 49 prostate magnetic resonance images (MRIs) done both with and without ERC. Prostate weight was calculated as follows: AP*TX*CC*π/6. Prostate dimensions and weight were obtained from radical prostatectomy pathology report.

RESULTS

After ERC placement, AP decreased by 0.71 cm [95% confidence interval (CI) 0.80-0.61], TX and CC increased by 0.26 cm (95% CI 0.18-0.33) and 0.25 cm (95% CI 0.16-0.35), respectively. Agreement between weight on pathology and MR was excellent: intraclass correlation coefficient (ICC) without ERC=0.96, ICC with ERC=0.90.

CONCLUSION

Although ERC distorts measurements and despite a tendency to underestimate the prostate weight, absolute agreement between prostate weight on pathology and MRI is excellent, both with and without ERC.

Prostate volume and biopsy tumor length are significant predictors for classical and redefined insignificant cancer on prostatectomy specimens in Japanese men with favorable pathologic features on biopsy

Background

Gleason pattern 3 less often has molecular abnormalities and often behaves indolent. It is controversial whether low grade small foci of prostate cancer (PCa) on biopsy could avoid immediate treatment or not, because substantial cases harbor unfavorable pathologic results on prostatectomy specimens. This study was designed to identify clinical predictors for classical and redefined insignificant cancer on prostatectomy specimens in Japanese men with favorable pathologic features on biopsy.

Methods

Retrospective review of 1040 PCa Japanese patients underwent radical prostatectomy between 2006 and 2013. Of those, 170 patients (16.3%) met the inclusion criteria of clinical stage ≤ cT2a, Gleason score (GS) ≤ 6, up to two positive biopsies, and no more than 50% of cancer involvement in any core. The associations between preoperative data and unfavorable pathologic results of prostatectomy specimens, and oncological outcome were analyzed. The definition of insignificant cancer consisted of pathologic stage ≤ pT2, GS ≤ 6, and an index tumor volume < 0.5 mL (classical) or 1.3 mL (redefined).

Results

Pathologic stage ≥ pT3, upgraded GS, index tumor volume ≥ 0.5 mL, and ≥ 1.3 mL were detected in 25 (14.7%), 77 (45.3%), 83 (48.8%), and 53 patients (31.2%), respectively. Less than half of cases had classical (41.2%) and redefined (47.6%) insignificant cancer. The 5-year recurrence-free survival was 86.8%, and the insignificant cancers essentially did not relapse regardless of the surgical margin status. MRI-estimated prostate volume, tumor length on biopsy, prostate-specific antigen density (PSAD), and findings of magnetic resonance imaging were associated with the presence of classical and redefined insignificant cancer. Large prostate volume and short tumor length on biopsy remained as independent predictors in multivariate analysis.

Conclusions

Favorable features of biopsy often are followed by adverse pathologic findings on prostatectomy specimens despite fulfilling the established criteria. The finding that prostate volume is important does not simply mirror many other studies showing PSAD is important, and the clinical criteria for risk assessment before definitive therapy or active surveillance should incorporate these significant factors other than clinical T-staging or PSAD to minimize under-estimation of cancer in Japanese patients with low-risk PCa.