Accuracy of biopsy Gleason scores from a large uropathology laboratory: use of a diagnostic protocol to minimize observer variability

Utility of dual read in the setting of prostate MRI interpretation

PURPOSE

The purpose of this study is to assess the utility of dual reader interpretation of prostate MRI in the evaluation/detection of prostate cancer, using the PI-RADS v2.1 scoring system.

METHODS

We performed a retrospective study to assess the utility of dual reader interpretation for prostate MRI. All MRI cases compiled for analysis were accompanied with prostate biopsy pathology reports that included Gleason scores to correlate to the MRI PI-RADS v2.1 score, tissue findings and location of pathology within the prostate gland. To assess for dual reader utility, two fellowship trained abdominal imagers (each with > 5 years of experience) provided independent and concurrent PI-RADS v2.1 scores on all included MRI examinations, which were then compared to the biopsy proven Gleason scores.

RESULTS

After application of inclusion criteria, 131 cases were used for analysis. The mean age of the cohort was 63.6 years. Sensitivity, specificity and positive/negative predictive values were calculated for each reader and concurrent scores. Reader 1 demonstrated 71.43% sensitivity, 85.39% specificity, 69.77% PPV and 86.36% NPV. Reader 2 demonstrated 83.33% sensitivity, 78.65% specificity, 64.81% PPV and 90.91% NPV. Concurrent reads demonstrated 78.57% sensitivity, 80.9% specificity, 66% PPV and 88.89% NPV. There was no statistically significant difference between the individual readers or concurrent reads (p = 0.79).

CONCLUSION

Our results highlight that dual reader interpretation in prostate MRI is not needed to detect clinically relevant tumor and that radiologists with experience and training in prostate MRI interpretation establish acceptable sensitivity and specificity marks on PI-RADS v2.1 assessment.

High Accuracy Indicators of Androgen Suppression Therapy Failure for Prostate Cancer-A Modeling Study

Simple Summary

Hormonal therapy for prostate cancer is often applied past the point of resistance, hence losing any future clinical value to the evolution of resistant strains. If the undesirable outcome of the treatment is forewarned, then clinicians can have an opportunity to adjust the treatment, which can result in better management of the cancer. Using a mechanistic mathematical model, we introduce two methods to enhance the accuracy of classical biomarkers for hormonal therapy failure. Our results show the value in measuring both prostate-specific antigen and androgen during hormonal treatment, which can potentially allow for better management of prostate cancer.

Abstract

Prostate cancer is a serious public health concern in the United States. The primary obstacle to effective long-term management for prostate cancer patients is the eventual development of treatment resistance. Due to the uniquely chaotic nature of the neoplastic genome, it is difficult to determine the evolution of tumor composition over the course of treatment. Hence, a drug is often applied continuously past the point of effectiveness, thereby losing any potential treatment combination with that drug permanently to resistance. If a clinician is aware of the timing of resistance to a particular drug, then they may have a crucial opportunity to adjust the treatment to retain the drug’s usefulness in a potential treatment combination or strategy. In this study, we investigate new methods of predicting treatment failure due to treatment resistance using a novel mechanistic model built on an evolutionary interpretation of Droop cell quota theory. We analyze our proposed methods using patient PSA and androgen data from a clinical trial of intermittent treatment with androgen deprivation therapy. Our results produce two indicators of treatment failure. The first indicator, proposed from the evolutionary nature of the cancer population, is calculated using our mathematical model with a predictive accuracy of 87.3% (sensitivity: 96.1%, specificity: 65%). The second indicator, conjectured from the implication of the first indicator, is calculated directly from serum androgen and PSA data with a predictive accuracy of 88.7% (sensitivity: 90.2%, specificity: 85%). Our results demonstrate the potential and feasibility of using an evolutionary tumor dynamics model in combination with the appropriate data to aid in the adaptive management of prostate cancer.

How does a prebiopsy mri approach for prostate cancer diagnosis affect prostatectomy upgrade rates?

BACKGROUND

To compare the pathologic upgrade and downgrade rates after radical prostatectomy (RP) between patients diagnosed by prebiopsy prostate MRI followed by a combination of systematic and fusion biopsy (ComBx) versus patients undergoing systematic biopsy only (SBx).

METHODS

A retrospective review of men undergoing RP at our institution between Jan 2014 and Mar 2020 was performed. These patients were separated into two independent cohorts based on two approaches: Patients receiving prebiopsy prostate MRI during initial evaluation and those who did not receive MRI. Patients with positive MRI findings underwent subsequent ComBx to confirm diagnosis while those without MRI underwent standard trans-rectal ultrasound (TRUS) guided systematic 12-core biopsy (SBx). Primary outcomes were rates of pathological upgrade (prostatectomy grade higher than grade determined at time of biopsy) and downgrade (prostatectomy grade lower than biopsy grade).

RESULTS

A total of 213 patients undergoing radical prostatectomy, 91 diagnosed via a prebiopsy MRI and ComBx approach and 122 diagnosed by a traditional SBx approach, were included in the study. There was no significant difference between age, PSA, or positive family history between the two cohorts. Of the 91 patients who received prebiopsy MRI, 88 patients were determined to have a PIRADS 4 or 5 lesion. Patients who received MRI and subsequent ComBx had a lower rate of any pathological upgrade after RP (9.89% vs. 22.13%, P = 0.018) without a significant difference in pathologic downgrade rate (28.57% vs. 18.85%, P = 0.095). On multivariable logistic regression, receiving prebiopsy MRI during initial evaluation was the single negative independent predictor of pathologic upgrade (OR = 0.23, P = 0.017). A prebiopsy MRI approach was also the single predictor of pathologic downgrade (OR = 3.13, P = 0.041).

CONCLUSIONS

Patients receiving prebiopsy MRI during prostate cancer evaluation were less likely to have their PCa upgraded. Furthermore, although diagnosis via MRI and subsequent ComBx was associated with an increased rate of downgrades after RP, relatively few resulted in a downgrade from clinically significant to clinically insignificant cancer.

Diagnostic Accuracy of 68Ga-PSMA-11 PET/MRI Compared with Multiparametric MRI in the Detection of Prostate Cancer

Purpose To compare the diagnostic accuracy of gallium 68 (⁶⁸Ga)-labeled prostate-specific membrane antigen (PSMA)-11 PET/MRI with that of multiparametric MRI in the detection of prostate cancer. Materials and Methods The authors performed a retrospective study of men with biopsy-proven prostate cancer who underwent simultaneous ⁶⁸Ga-PSMA-11 PET/MRI before radical prostatectomy between December 2015 and June 2017. The reference standard was whole-mount pathologic examination. Readers were blinded to radiologic and pathologic findings. Tumor localization was based on 30 anatomic regions. Region-specific sensitivity and specificity were calculated for PET/MRI and multiparametric MRI by using raw stringent and alternative neighboring approaches. Maximum standardized uptake value (SUV_max) in the tumor and Prostate Imaging Reporting and Data System (PI-RADS) version 2 grade were compared with tumor Gleason score. Generalized estimating equations were used to estimate population-averaged sensitivity and specificity and to determine the association between tumor characteristics and SUV_max or PI-RADS score. Results Thirty-two men (median age, 68 years; interquartile range: 62-71 years) were imaged. The region-specific sensitivities of PET/MRI and multiparametric MRI were 74% (95% confidence interval [CI]: 70%, 77%) and 50% (95% CI: 45%, 0.54%), respectively, with the alternative neighboring approach (P < .001 for both) and 73% (95% CI: 68%, 79%) and 69% (95% CI: 62%, 75%), respectively, with the population-averaged generalized estimating equation (P = .04). Region-specific specificity of PET/MRI was similar to that of multiparametric MRI with the alternative neighboring approach (88% [95% CI: 85%, 91%] vs 90% [95% CI: 87%, 92%], P = .99) and in population-averaged estimates (70% [95% CI: 64%, 76%] vs 70% [95% CI: 64%, 75%], P = .99). SUV_max was associated with a Gleason score of 7 and higher (odds ratio: 1.71 [95% CI: 1.27, 2.31], P < .001). Conclusion The sensitivity of gallium 68-labeled prostate-specific membrane antigen-11 PET/MRI in the detection of prostate cancer is better than that of multiparametric MRI. © RSNA, 2018 See also the editorial by Civelek in this issue.

Personalized schedules for surveillance of low-risk prostate cancer patients

Low‐risk prostate cancer patients enrolled in active surveillance (AS) programs commonly undergo biopsies on a frequent basis for examination of cancer progression. AS programs employ a fixed schedule of biopsies for all patients. Such fixed and frequent schedules may schedule unnecessary biopsies. Since biopsies are burdensome, patients do not always comply with the schedule, which increases the risk of delayed detection of cancer progression. Motivated by the world's largest AS program, Prostate Cancer Research International Active Surveillance (PRIAS), we present personalized schedules for biopsies to counter these problems. Using joint models for time‐to‐event and longitudinal data, our methods combine information from historical prostate‐specific antigen levels and repeat biopsy results of a patient, to schedule the next biopsy. We also present methods to compare personalized schedules with existing biopsy schedules.

Pilot study for supervised target detection applied to spatially registered multiparametric MRI in order to non-invasively score prostate cancer

BACKGROUND

Gleason Score (GS) is a validated predictor of prostate cancer (PCa) disease progression and outcomes. GS from invasive needle biopsies suffers from significant inter-observer variability and possible sampling error, leading to underestimating disease severity ("underscoring") and can result in possible complications. A robust non-invasive image-based approach is, therefore, needed.

PURPOSE

Use spatially registered multi-parametric MRI (MP-MRI), signatures, and supervised target detection algorithms (STDA) to non-invasively GS PCa at the voxel level.

METHODS AND MATERIALS

This study retrospectively analyzed 26 MP-MRI from The Cancer Imaging Archive. The MP-MRI (T2, Diffusion Weighted, Dynamic Contrast Enhanced) were spatially registered to each other, combined into stacks, and stitched together to form hypercubes. Multi-parametric (or multi-spectral) signatures derived from a training set of registered MP-MRI were transformed using statistics-based Whitening-Dewhitening (WD). Transformed signatures were inserted into STDA (having conical decision surfaces) applied to registered MP-MRI determined the tumor GS. The MRI-derived GS was quantitatively compared to the pathologist's assessment of the histology of sectioned whole mount prostates from patients who underwent radical prostatectomy. In addition, a meta-analysis of 17 studies of needle biopsy determined GS with confusion matrices and was compared to the MRI-determined GS.

RESULTS

STDA and histology determined GS are highly correlated (R = 0.86, p < 0.02). STDA more accurately determined GS and reduced GS underscoring of PCa relative to needle biopsy as summarized by meta-analysis (p < 0.05).

CONCLUSION

This pilot study found registered MP-MRI, STDA, and WD transforms of signatures shows promise in non-invasively GS PCa and reducing underscoring with high spatial resolution.

Analysis of histological findings obtained combining US/mp-MRI fusion-guided biopsies with systematic US biopsies: mp-MRI role in prostate cancer detection and false negative

AIMS AND OBJECTIVES

To evaluate the diagnostic accuracy of mp-MRI correlating US/mp-MRI fusion-guided biopsy with systematic random US-guided biopsy in prostate cancer diagnosis.

MATERIALS AND METHODS

137 suspected prostatic abnormalities were identified on mp-MRI (1.5T) in 96 patients and classified according to PI-RADS score v2. All target lesions underwent US/mp-MRI fusion biopsy and prostatic sampling was completed by US-guided systematic random 12-core biopsies. Histological analysis and Gleason score were established for all the samples, both target lesions defined by mp-MRI, and random biopsies. PI-RADS score was correlated with the histological results, divided in three groups (benign tissue, atypia and carcinoma) and with Gleason groups, divided in four categories considering the new Grading system of the ISUP 2014, using t test. Multivariate analysis was used to correlate PI-RADS and Gleason categories to PSA level and abnormalities axial diameter. When the random core biopsies showed carcinoma (mp-MRI false-negatives), PSA value and lesions Gleason median value were compared with those of carcinomas identified by mp-MRI (true-positives), using t test.

RESULTS

There was statistically significant difference between PI-RADS score in carcinoma, atypia and benign lesions groups (4.41, 3.61 and 3.24, respectively) and between PI-RADS score in Gleason < 7 group and Gleason > 7 group (4.14 and 4.79, respectively). mp-MRI performance was more accurate for lesions > 15 mm and in patients with PSA > 6 ng/ml. In systematic sampling, 130 (11.25%) mp-MRI false-negative were identified. There was no statistic difference in Gleason median value (7.0 vs 7.06) between this group and the mp-MRI true-positives, but a significant lower PSA median value was demonstrated (7.08 vs 7.53 ng/ml).

CONCLUSION

mp-MRI remains the imaging modality of choice to identify PCa lesions. Integrating US-guided random sampling with US/mp-MRI fusion target lesions sampling, 3.49% of false-negative were identified.

Estimate of false-positive breast cancer diagnoses from accuracy studies: a systematic review

Background

False-positive histological diagnoses have the same consequences of overdiagnosis in terms of unnecessary treatment. The aim of this systematic review is to assess their frequency at needle core biopsy (CB) and/or surgical excision of the breast.

Methods

PubMed, Embase, Cochrane Library were systematically searched up to 30 October 2015. Eligibility criteria: cross-sectional studies assessing diagnostic accuracy of CB compared with surgical excision; studies assessing reproducibility of pathologists reading the same slides. Outcomes: false-positive rates; Misclassification of Benign as Malignant (MBM) histological diagnosis; K statistic. Independent reviewers extracted data and assessed quality using an adapted QUADAS-2 tool.

Results

Sixteen studies assessed CB false-positive rates. In 10 studies (41 989 screen-detected lesions), the range of false-positive rates was 0%–7.1%. Twenty-seven studies assessed pathologists' reproducibility. Studies with consecutive, random or stratified samples of all the specimens: at CB the MBM range was 0.25%–2.4% (K values 0.83–0.98); at surgical excision, it was 0.67%–1.2% (K values 0.86–0.94). Studies with enriched samples: the MBM range was 1.4%–6.2% (K values 0.57–0.86). Studies of cases selected for second opinion: the MBM range was 0.29%–12.2% (K values 0.48 and 0.50).

Conclusions

High heterogeneity of the included studies precluded formal pooling estimates. When considering studies of higher sample size or methodological quality, false-positive rates and MBM are around 1%. The impact of false-positive histological diagnoses of breast cancer on unnecessary treatment, as well as that of overdiagnosis, is not negligible and is of importance in clinical practice.

Detecting Prostate Cancer

BACKGROUND

When prostate cancer is suspected, the prostate gland is biopsied with the aid of transrectal ultrasound (TRUS). The sensitivity of prostatic biopsy is about 50%. The fusion of magnetic resonance imaging (MRI) data with TRUS enables the targeted biopsy of suspicious areas. We studied whether this improves the detection of prostate cancer.

METHODS

168 men with suspected prostate cancer underwent prostate MRI after a previous negative biopsy. Suspicious lesions were assessed with the classification of the Prostate Imaging Reporting and Data System and biopsied in targeted fashion with the aid of fused MRI and TRUS. At the same sitting, a systematic biopsy with at least 12 biopsy cores was performed.

RESULTS

Prostate cancer was detected in 71 patients (42.3%; 95% CI, 35.05-49.82). The detection rate of fusion-assisted targeted biopsy was 19% (95% CI, 13.83-25.65), compared to 37.5% (95% CI, 30.54-45.02) with systematic biopsy. Clinically significant cancer was more commonly revealed by targeted biopsy (84.4%; 95% CI, 68.25-93.14) than by systematic biopsy (65.1%; 95% CI, 52.75-75.67). In 7 patients with normal MRI findings, cancer was detected by systematic biopsy alone. Compared to systematic biopsy, targeted biopsy had a higher overall detection rate (16.5% vs. 6.3%), a higher rate of infiltration per core (30% vs. 10%), and a higher rate of detection of poorly differentiated carcinoma (18.5% vs. 3%). Patients with negative biopsies did not undergo any further observation.

CONCLUSION

MRI/TRUS fusion-assisted targeted biopsy improves the detection rate of prostate cancer after a previous negative biopsy. Targeted biopsy is more likely to reveal clinically significant cancer than systematic biopsy; nevertheless, systematic biopsy should still be performed, even if the MRI findings are negative.

Visually Meaningful Histopathological Features for Automatic Grading of Prostate Cancer

Histopathologic features, particularly Gleason grading system, have contributed significantly to the diagnosis, treatment, and prognosis of prostate cancer for decades. However, prostate cancer demonstrates enormous heterogeneity in biological behavior, thus establishing improved prognostic and predictive markers is particularly important to personalize therapy of men with clinically localized and newly diagnosed malignancy. Many automated grading systems have been developed for Gleason grading but acceptance in the medical community has been lacking due to poor interpretability. To overcome this problem, we developed a set of visually meaningful features to differentiate between low- and high-grade prostate cancer. The visually meaningful feature set consists of luminal and architectural features. For luminal features, we compute: 1) the shortest path from the nuclei to their closest luminal spaces; 2) ratio of the epithelial nuclei to the total number of nuclei. A nucleus is considered an epithelial nucleus if the shortest path between it and the luminal space does not contain any other nucleus; 3) average shortest distance of all nuclei to their closest luminal spaces. For architectural features, we compute directional changes in stroma and nuclei using directional filter banks. These features are utilized to create two subspaces; one for prostate images histopathologically assessed as low grade and the other for high grade. The grade associated with a subspace, which results in the minimum reconstruction error is considered as the prediction for the test image. For training, we utilized 43 regions of interest (ROI) images, which were extracted from 25 prostate whole slide images of The Cancer Genome Atlas (TCGA) database. For testing, we utilized an independent dataset of 88 ROIs extracted from 30 prostate whole slide images. The method resulted in 93.0% and 97.6% training and testing accuracies, respectively, for the spectrum of cases considered. The application of visually meaningful features provided promising levels of accuracy and consistency for grading prostate cancer.

Diagnosis of "Poorly Formed Glands" Gleason Pattern 4 Prostatic Adenocarcinoma on Needle Biopsy: An Interobserver Reproducibility Study Among Urologic Pathologists With Recommendations

Accurate recognition of Gleason pattern (GP) 4 prostate carcinoma (PCa) on needle biopsy is critical for patient management and prognostication. "Poorly formed glands" are the most common GP4 subpattern. We studied the diagnostic reproducibility and the quantitative threshold of grading GP4 "poorly formed glands" and the criteria to distinguish them from tangentially sectioned GP3 glands. Seventeen urologic pathologists were first queried for the definition of "poorly formed glands" using cases representing a spectrum of PCa glandular differentiation. Cancer glands with no or rare lumens, elongated compressed glands, and elongated nests were considered "poorly formed glands" by consensus. Participants then graded a second set of 23 PCa cases that potentially contained "poorly formed glands" with a fair interobserver agreement (κ = 0.34). The consensus diagnoses, defined as agreement by > 70% participants, were then correlated with the quantitative (≤ 5, 6 to 10, >10) and topographic features of poorly formed glands (clustered, immediately adjacent to, and intermixed with other well-formed PCa glands) in each case. Poorly formed glands immediately adjacent to other well-formed glands regardless of their number and small foci of ≤ 5 poorly formed glands regardless of their location were not graded as GP4. In contrast, large foci of >10 poorly formed glands that were not immediately adjacent to well-formed glands were graded as GP4. Grading "poorly formed glands" is challenging. Some morphologic features are, however, reproducible for and against a GP4 diagnosis. This study represents an important step in standardization of grading of "poorly formed glands" based on quantitative and topographic morphologic features.

Predicting the risk of harboring high-grade disease for patients diagnosed with prostate cancer scored as Gleason ≤ 6 on biopsy cores

PURPOSE

Biopsy and final pathological Gleason score (GS) are inconstantly correlated with each other. The aim of the current study was to develop and validate a predictive score to screen patients diagnosed with a biopsy GS ≤ 6 prostate cancer (PCa) at risk of GS upgrading.

METHODS

Clinical and pathological data of 1,179 patients managed with radical prostatectomy for a biopsy GS ≤ 6, clinical stage ≤ T2b and preoperative PSA ≤ 20 ng/ml PCa were collected. The population study was randomly split into a development (n = 822) and a validation (n = 357) cohort. A prognostic score was established using the independent factors related to GS upgrading identified in multivariate analysis. The cutoff value derived from the area under the receiver operating characteristic curve of the score.

RESULTS

After RP, the rate of GS upgrading was 56.7%. In multivariate analysis, length of cancer per core > 5 mm (OR 2.938; p < 0.001), PSA level > 15 ng/ml (OR 2.365; p = 0.01), age > 70 (OR 1.746; p = 0.016), number of biopsy cores > 12 (OR 0.696; p = 0.041) and prostate weight > 50 g (OR 0.656; CI; p < 0.007) were independent predictive factors of GS upgrading. A score ranged between -4 and 12 with a cutoff value of 2 was established. In the development cohort, the accuracy of predictive score was 63.7% and the positive predictive value was 71.2%. Results were confirmed in the validation cohort.

CONCLUSION

This predictive tool might be used to screen patients initially diagnosed with low-grade PCa but harboring occult high-grade disease.

Concordance between transrectal ultrasound guided biopsy results and radical prostatectomy final pathology: Are we getting better at predicting final pathology?

INTRODUCTION

Inaccuracy in biopsy Gleason scoring poses a risk to men who may then receive inappropriate treatment. We assess whether there was a change in discordance rates between biopsy and radical prostatectomy at our institution in recent years, while considering the implementation of active surveillance and the shift in biopsy scores caused by the 2005 International Society of Urologic Pathology update to the Gleason scoring protocol.

METHODS

We reviewed patients who underwent radical prostatectomy at our institution between May 2004 and April 2011. We analyzed clinical and pathological correlates of upgrading in 3 subgroups: Gleason sum (GS) 6/6, GS6/7 and GS7/7, where the sum preceding the dash was determined from biopsy and the subsequent sum was determined from the radical prostatectomy specimen. We applied the log-rank test and Cox model to a Kaplan Meier analysis of biochemical recurrence in the subgroups, and also mapped GS6/7 discordance over time.

RESULTS

In total, 1717 patients met our inclusion criteria. The 3 subgroups had significantly different mean prostate-specific antigen, patient age, tumour volume, margin status, pathologic stage, prostate weight, transrectal ultrasound volume and rate of progression (p < 0.05). We noted a multiphasic trend with a fall in discordance after 2005. However, there was no sustained trend over the study period taken as a whole (p = 0.06).

CONCLUSIONS

Although no sustained trend was observed, the falling discordance after 2005 may reflect the accommodation to the Gleason scoring update, while the gradual adoption of active surveillance may have led to the otherwise increasing trends. However, our observations may also be spurious biopsy sampling errors.

Improving the Gleason grading accuracy of transrectal ultrasound-guided biopsy

BACKGROUND

Transrectal ultrasound (TRUS)-guided prostate biopsy is the technique of choice for the assessment of clinical suspicion of prostate cancer (PC) based on abnormal digital rectal examination (DRE) and/or elevated or rising levels of prostate-specific antigen (PSA).

PURPOSE

To identify factors involved in TRUS-guided prostate biopsy, which can be modified by radiologists in order to improve Gleason score (GS) accuracy, and to assess the influence of clinical variables.

MATERIAL AND METHODS

We carried out a retrospective review of the records of 185 patients with PC treated surgically at our hospital between 2005 and 2008. Biopsy schemes were classified according to the number of cores (≤7, 8-9, 10-11, 12-15) and the needle length (11, 16, 20 mm). Clinical characteristics - age, family history of PC, DRE, PSA levels, and sonographic data - and prostatectomy GS (pGS) were collected.

RESULTS

Non-random concordance between biopsy Gleason score (bGS) and pGS was obtained for 36% of patients (P < 0.001). Under- and over-staging were 30% and 4%, respectively. Concordance was correlated with the core number (45% for ≤7, 54% for 8-9, 85% for 10-11, and 80% for 12-15; P < 0.001), but not with the needle length. The concordance rate showed a seven-fold increase when 10-11 cores were obtained (95% CI, 2-18; P < 0.001) compared to those cases in which the core number obtained was ≤7. Among clinical variables, only PSA correlated with concordance, showing an inverse relationship.

CONCLUSION

The Gleason correlation values were not improved when 12 or more cores were collected. These values reached a plateau beyond that number of samples. Therefore, when determining treatment strategies, physicians must consider the biopsy scheme used since it has proven to be a predictor of the accuracy of the PC grading system.

Differences in Upgrading of Prostate Cancer in Prostatectomies between Community and Academic Practices

Objective. To determine whether initial biopsy performed by community or academic urologists affected rates of Gleason upgrading at a tertiary referral center. Gleason upgrading from biopsy to radical prostatectomy (RP) is an important event as treatment decisions are made based on the biopsy score. Materials and Methods. We identified men undergoing RP for Gleason 3 + 3 or 3 + 4 disease at a tertiary care academic center. Biopsy performed in the community was centrally reviewed at the academic center. Multivariate logistic regression was used to determine factors associated with Gleason upgrading. Results. We reviewed 1,348 men. There was no difference in upgrading whether the biopsy was performed at academic or community sites (OR 0.9, 95% CI 0.7-1.2). Increased risk of upgrading was seen in those with >1 positive core, older men, and those with higher PSAs. Secondary pattern 4 and larger prostate size were associated with a reduction in risk of upgrading. Compared to the smallest quartile of prostate size (<35 g), those in the highest quartile (>56 g) had a 49% reduction in risk of upgrading (OR 0.51, 95% CI 0.3-0.7). Conclusion. There was no difference in upgrading between where the biopsy was performed and community and academic urologists.

Magnetic resonance imaging/ultrasound-fusion biopsy significantly upgrades prostate cancer versus systematic 12-core transrectal ultrasound biopsy

BACKGROUND

Gleason scores from standard, 12-core prostate biopsies are upgraded historically in 25-33% of patients. Multiparametric prostate magnetic resonance imaging (MP-MRI) with ultrasound (US)-targeted fusion biopsy may better sample the true gland pathology.

OBJECTIVE

The rate of Gleason score upgrading from an MRI/US-fusion-guided prostate-biopsy platform is compared with a standard 12-core biopsy regimen alone.

DESIGN, SETTING, AND PARTICIPANTS

There were 582 subjects enrolled from August 2007 through August 2012 in a prospective trial comparing systematic, extended 12-core transrectal ultrasound biopsies to targeted MRI/US-fusion-guided prostate biopsies performed during the same biopsy session.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The highest Gleason score from each biopsy method was compared.

INTERVENTIONS

An MRI/US-fusion-guided platform with electromagnetic tracking was used for the performance of the fusion-guided biopsies.

RESULTS AND LIMITATIONS

A diagnosis of prostate cancer (PCa) was made in 315 (54%) of the patients. Addition of targeted biopsy led to Gleason upgrading in 81 (32%) cases. Targeted biopsy detected 67% more Gleason ≥4+3 tumors than 12-core biopsy alone and missed 36% of Gleason ≤3+4 tumors, thus mitigating the detection of lower-grade disease. Conversely, 12-core biopsy led to upgrading in 67 (26%) cases over targeted biopsy alone but only detected 8% more Gleason ≥4+3 tumors. On multivariate analysis, MP-MRI suspicion was associated with Gleason score upgrading in the targeted lesions (p<0.001). The main limitation of this study was that definitive pathology from radical prostatectomy was not available.

CONCLUSIONS

MRI/US-fusion-guided biopsy upgrades and detects PCa of higher Gleason score in 32% of patients compared with traditional 12-core biopsy alone. Targeted biopsy technique preferentially detects higher-grade PCa while missing lower-grade tumors.

Clinical and pathological variables that predict changes in tumour grade after radical prostatectomy in patients with prostate cancer

INTRODUCTION

Preoperative Gleason score is crucial, in combination with other preoperative parameters, in selecting the appropriate treatment for patients with clinically localized prostate cancer. The aim of the present study is to determine the clinical and pathological variables that can predict differences in Gleason score between biopsy and radical prostatectomy.

METHODS

We retrospectively analyzed the medical records of 302 patients who had a radical prostatectomy between January 2005 and September 2010. The association between grade changes and preoperative Gleason score, age, prostate volume, prostate-specific antigen (PSA), PSA density, number of biopsy cores, presence of prostatitis and high-grade prostatic intraepithelial neoplasia was analyzed. We also conducted a secondary analysis of the factors that influence upgrading in patients with preoperative Gleason score ≤6 (group 1) and downgrading in patients with Gleason score ≤7 (group 2).

RESULTS

No difference in Gleason score was noted in 44.3% of patients, while a downgrade was noted in 13.7% and upgrade in 42.1%. About 2/3 of patients with a Gleason score of ≤6 upgraded after radical prostatectomy. PSA density (p = 0.008) and prostate volume (p = 0.032) were significantly correlated with upgrade. No significant predictors were found for patients with Gleason score ≤7 who downgraded postoperatively.

CONCLUSION

Smaller prostate volume and higher values of PSA density are predictors for upgrade in patients with biopsy Gleason score ≤6 and this should be considered when deferred treatment modalities are planned.

Factors predicting Gleason score 6 upgrading after radical prostatectomy

Objectives

Prostate cancer Gleason score 6 is the most common score detected on prostatic biopsy. We analyzed the clinical parameters that predict the likelihood of Gleason score upgrading after radical prostatectomy.

Methods

The study population consisted of 241 patients who underwent radical retropubic prostatectomy between Feb 2002 and Dec 2007 for Gleason score 6 adenocarcinoma. The influence of preoperative parameters on the probability of a Gleason score upgrading after surgery was evaluated using multivariate logistic regression and ROC curves.

Results

Gleason score upgrade was found in 92 of 241 patients (38.2%). Multivariate logistic regression analysis showed that only percentage of cancer in dominant lobe and prostate weight were significant predictors for Gleason score upgrading (p = 0.043 and p = 0.006, respectively). ROC curves showed that prostate weight and PSA density were only two independent significant parameters for prediction of upgrade (AUC – 0.634, p <0.0001 and 0.604, p = 0.006, respectively). Gleason score upgrading was observed to be accompanied by significantly higher rates of extra prostatic extension (p <0.001) and seminal vesicle invasion (p = 0.002).

Conclusions

Almost forty percent of tumors graded Gleason 6 at biopsy are Gleason 7 at surgery. Upgraded tumors significantly associated with adverse pathological features. The probability of Gleason score upgrade can be predicted using prostate weight and PSA density as independent parameters.

The Use of Immunohistochemistry for Biomarker Assessment—Can It Compete with Other Technologies?

A morphology-based assay such as immunohistochemistry (IHC) should be a highly effective means to define the expression of a target molecule of interest, especially if the target is a protein. However, over the past decade, IHC as a platform for biomarkers has been challenged by more quantitative molecular assays with reference standards but that lack morphologic context. For IHC to be considered a “top-tier” biomarker assay, it must provide truly quantitative data on par with non-morphologic assays, which means it needs to be run with reference standards. However, creating such standards for IHC will require optimizing all aspects of tissue collection, fixation, section thickness, morphologic criteria for assessment, staining processes, digitization of images, and image analysis. This will also require anatomic pathology to evolve from a discipline that is descriptive to one that is quantitative. A major step in this transformation will be replacing traditional ocular microscopes with computer monitors and whole slide images, for without digitization, there can be no accurate quantitation; without quantitation, there can be no standardization; and without standardization, the value of morphology-based IHC assays will not be realized.

Preoperative nomograms incorporating magnetic resonance imaging and spectroscopy for prediction of insignificant prostate cancer

Study Type--Prognosis (case series). Level of Evidence 4. What's known on the subject? And what does the study add? Nomograms are available that combine clinical and biopsy findings to predict the probability of pathologically insignificant prostate cancer in patients with clinically low-risk disease. Based on data from patients with Gleason score 6, clinical stage ≤ T2a and PSA <20 ng/ml, our group developed the first nomogram models for predicting insignificant prostate cancer that incorporated clinical data, detailed biopsy data and findings from MRI or MRI/MRSI (BJU Int. 2007;99(4):786-93). When tested retrospectively, these MR models performed significantly better than standard clinical models with and without detailed biopsy data. We prospectively validated the previously published MR-based nomogram models in a population of patients with Gleason score 6, clinical stage ≤ T2a and PSA <10 ng/ml. Based on data from this same population, we also developed two new models for predicting insignificant prostate cancer that combine MR findings and clinical data without detailed biopsy data. Upon initial testing, the new MR models performed significantly better than a clinical model lacking detailed biopsy data.

OBJECTIVES

• To validate previously published nomograms for predicting insignificant prostate cancer (PCa) that incorporate clinical data, percentage of biopsy cores positive (%BC+) and magnetic resonance imaging (MRI) or MRI/MR spectroscopic imaging (MRSI) results. • We also designed new nomogram models incorporating magnetic resonance results and clinical data without detailed biopsy data. Nomograms for predicting insignificant PCa can help physicians counsel patients with clinically low-risk disease who are choosing between active surveillance and definitive therapy.

PATIENTS AND METHODS

• In total, 181 low-risk PCa patients (clinical stage T1c-T2a, prostate-specific antigen level <10 ng/mL, biopsy Gleason score of 6) had MRI/MRSI before surgery. • For MRI and MRI/MRSI, the probability of insignificant PCa was recorded prospectively and independently by two radiologists on a scale from 0 (definitely insignificant) to 3 (definitely significant PCa). • Insignificant PCa was defined on surgical pathology. • There were four models incorporating MRI or MRI/MRSI and clinical data with and without %BC+ that were compared with a base clinical model without %BC and a more comprehensive clinical model with %BC+. Prediction accuracy was assessed using areas under receiver-operator characteristic curves.

RESULTS

• At pathology, 27% of patients had insignificant PCa, and the Gleason score was upgraded in 56.4% of patients. • For both readers, all magnetic resonance models performed significantly better than the base clinical model (P ≤ 0.05 for all) and similarly to the more comprehensive clinical model.

CONCLUSIONS

• Existing models incorporating magnetic resonance data, clinical data and %BC+ for predicting the probability of insignificant PCa were validated. • All MR-inclusive models performed significantly better than the base clinical model.

Pathological correlation between needle biopsy and radical prostatectomy specimen in patients with localized prostate cancer

OBJECTIVE

This study aims to evaluate the accuracy of transrectal ultrasound (TRUS) guided prostate biopsies in predicting pathological grading and tumour distribution in the final pathological specimen of patients who underwent radical prostatectomy for clinically localized prostate cancer. The study ultimately aims to gain more understanding of the pathological behaviour of prostate cancer and the limitations of the currently available diagnostic and prognostic tools.

MATERIAL AND METHODS

We reviewed the records of 100 patients with localized carcinoma of the prostate diagnosed by TRUS-guided prostate biopsy and treated with radical retropubic prostatectomy, comparing tumour laterality and Gleason score in core biopsies with tumour distribution and Gleason score of the surgical specimen. We then correlated both results to diagnostic and prognostic variables such as prostate specific antigen (PSA) values and surgical margins.

RESULTS

All 44 patients with bilateral disease on needle biopsy had bilateral disease on final pathology, with 15 of these patients (34%) having positive margins. Of the 56 patients with unilateral disease on biopsy, 37 (66%) had bilateral disease on final pathology; however, only 4 of them (7%) had positive margins (p < 0.001). Median Gleason score on final pathology was upgraded to 7, compared with a median score of 6 on biopsies. Stratifying patients to 2 groups based on their PSA level (group 1: PSA < 10 ng/mL, 72 patients; group 2: PSA > 10ng/mL, 28 patients), revealed that 57 patients (79%) in group 1 and 24 patients (85%) in group 2 had bilateral disease. In addition, 13 patients (18%) in group 1 and 6 patients (21%) in group 2 had positive margins.

CONCLUSIONS

Sixty-six percent of patients with unilateral disease on needle biopsy had bilateral disease on final pathology, but this does not increase their rate of having positive margins. Gleason score is upgraded from 6 to 7. PSA did not seem to affect laterality of disease in patients selected for radical prostatectomy.

Interactive digital slides with heat maps: a novel method to improve the reproducibility of Gleason grading

Our aims were to analyze reporting of Gleason pattern (GP) 3 and 4 prostate cancer with the ISUP 2005 Gleason grading and to collect consensus cases for standardization. We scanned 25 prostate biopsy cores diagnosed as Gleason score (GS) 6-7. Fifteen genitourinary pathologists graded the digital slides and circled GP 4 and 5 in a slide viewer. Grading difficulty was scored as 1-3. GP 4 components were classified as type 1 (cribriform), 2 (fused), or 3 (poorly formed glands). A GS of 5-6, 7 (3 + 4), 7 (4 + 3), and 8-9 was given in 29%, 41%, 19%, and 10% (mean GS 6.84, range 6.44-7.36). In 15 cases, at least 67% of observers agreed on GS groups (consensus cases). Mean interobserver weighted kappa for GS groups was 0.43. Mean difficulty scores in consensus and non-consensus cases were 1.44 and 1.66 (p = 0.003). Pattern 4 types 1, 2, and 3 were seen in 28%, 86%, and 67% of GP 4. All three coexisted in 16% (11% and 23% in consensus and non-consensus cases, p = 0.03). Average estimated and calculated %GP 4/5 were 29% and 16%. After individual review, the experts met to analyze diagnostic difficulties. Areas of GP 4 and 5 were displayed as heat maps, which were helpful for identifying contentious areas. A key problem was to agree on minimal criteria for small foci of GP 4. In summary, the detection threshold for GP 4 in NBX needs to be better defined. This set of consensus cases may be useful for standardization.

Investigating FTIR based histopathology for the diagnosis of prostate cancer

Prostate cancer is the most common gender specific cancer. The current gold standard for diagnosis, histopathology, is subjective and limited by variation between different pathologists. The diagnostic problems associated with the correct grading and staging of prostate cancer (CaP) has led to an interest in the development of spectroscopic based diagnostic techniques. FTIR microspectroscopy used in combination with a Principal Component Discriminant Function Analysis (PC-DFA) was applied to investigate FTIR based histopathology for the diagnosis of CaP. In this paper we report the results of a large patient study in which FTIR has been proven to grade CaP tissue specimens to a high degree of sensitivity and specificity.

Upgrading the Gleason score in extended prostate biopsy: implications for treatment choice

PURPOSE

To determine the incidence of overestimation of Gleason score (GS) in extended prostate biopsy, and consequently circumventing unnecessary aggressive treatment.

METHODS AND MATERIALS

This is a retrospective study of 464 patients who underwent prostate biopsy and radical prostatectomy between January 2001 and November 2007. The GS from biopsy and radical prostatectomy were compared. The incidence of overestimation of GS in biopsies and tumor volume were studied. Multivariate analysis was applied to find parameters that predict upgrading the GS in prostate biopsy.

RESULTS

The exact agreement of GS between prostate biopsy and radical prostatectomy occurred in 56.9% of cases. In 29.1% cases it was underestimated, and it was overestimated in 14%. One hundred and six (22.8%) patients received a diagnosis of high GS (8, 9, or 10) in a prostate biopsy. In 29.2% of cases, the definitive Gleason Score was 7 or lower. In cases in which GS was overestimated in the biopsy, tumors were significantly smaller. In multivariate analysis, the total percentage of tumor was the only independent factor in overestimation of GS. Tumors occupying less than 33% of cores had a 5.6-fold greater chance of being overestimated.

CONCLUSION

In the extended biopsy era and after the International Society of Urological Pathology consensus on GS, almost one third of tumors considered to have high GS at the biopsy may be intermediate-risk cancers. In that condition, tumors are smaller in biopsy. This should be remembered by professionals involved with prostate cancer to avoid overtreatment and undesirable side effects.

Comparing the Gleason prostate biopsy and Gleason prostatectomy grading system: the Lahey Clinic Medical Center experience and an international meta-analysis

BACKGROUND

The accuracy of the prostate biopsy Gleason grade to predict the prostatectomy Gleason grade varies tremendously in the literature.

OBJECTIVES

Determine the accuracy and distribution of the prostate biopsy Gleason grade and prostatectomy Gleason grade at LCMC (Lahey Clinic Medical Center) and worldwide.

DESIGN, SETTING, AND PARTICIPANTS

Participants included 2890 patients who had not received preoperative hormones, and for whom preoperative and postoperative Gleason sums were available. Participants underwent radical prostatectomy at LCMC, an academic referral center, from 1982-2007. Studies for the meta-analysis were selected from Medline: 1994-2007. Search criteria included keywords "Gleason," "biopsy," and "prostatectomy," >/=200 patients, and whether the biopsy and prostatectomy Gleason scores categorized into the predefined Gleason grades. The meta-analysis included 15 studies and the LCMC database for 14,839 total patients.

MEASUREMENTS

Gleason scores 2-6, 7, and 8-10 were converted to low, moderate, and high grade, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value were calculated. The kappa statistic and chi-square were used to compare biopsy and prostatectomy grades.

RESULTS AND LIMITATIONS

The percentage of patients in whom the prostatectomy grade was accurately predicted, upgraded, and downgraded was 58%, 36%, and 5% at LCMC and 63%, 30%, and 7% in the meta-analysis, respectively. The PPV for low-, moderate-, and high-grade cancer was 54%, 70%, and 60% for LCMC and 62%, 70%, and 50% for the meta-analysis, respectively. The sensitivity decreased with increasing Gleason grade (low, moderate, and high) for LCMC (91%, 38%, 28%) and the meta-analysis (90%, 40%, 33%), respectively. The distribution of low-, moderate-, and high-grade cancer on biopsy (69%, 25%, and 6%) and prostatectomy specimen (47%, 44%, and 9%) demonstrated only "fair" agreement (kappa, 0.37).

CONCLUSIONS

Patients and practitioners need to be cognizant of significant upgrading for low-grade disease and the downgrading for high-grade disease.

Well-differentiated prostate cancer in core biopsy specimens may be associated with extraprostatic disease

CONTEXT AND OBJECTIVE

Accurate determination of the Gleason score in prostate core biopsy specimens is crucial in selecting the type of prostate cancer treatment, especially for patients with well-differentiated tumors (Gleason score 2 to 4). For such patients, an inaccurate biopsy score may result in a therapeutic intervention that is too conservative. We evaluate the role of Gleason score 2-4 in prostate core-needle biopsies for predicting the final pathological staging following radical prostatectomy.

DESIGN AND SETTING

Retrospective study at Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo.

METHODS

We analyzed the medical records of 120 consecutive patients who underwent radical retropubic prostatectomy to treat clinical localized prostate cancer at our institution between December 2001 and July 2006. Thirty-two of these patients presented well-differentiated tumors (Gleason score 2 to 4) in biopsy specimens and were included in the study. The Gleason scores of the core-needle biopsies were compared with the pathological staging of the surgical specimens.

RESULTS

Sixteen of the 32 patients (50%) presented moderately differentiated tumors (Gleason score 5 to 7) in surgical specimens. Eighteen patients (56%) had tumors with involvement of the prostate capsule and ten (31%) had involvement of adjacent organs. Evaluating the 16 patients that maintained Gleason scores of 2 to 4 in the pathological staging of the surgical specimens, 11 (68.7%) had focal invasion of the prostate capsule and five (31.25%) had organ-confined disease.

CONCLUSION

Well-differentiated tumors (Gleason score 2 to 4) seen in biopsies are not predictive of organ-confined disease.

Prostate cancer volume at biopsy predicts clinically significant upgrading

PURPOSE

A significant proportion of patients with prostate cancer with Gleason score 6 disease at biopsy is upgraded to Gleason score 7 or higher after radical prostatectomy, increasing the risk of adverse outcome. We identified clinical and pathological parameters that predict pathological upgrading in this population.

MATERIALS AND METHODS

A total of 268 patients with biopsy Gleason score 6 prostate cancer who underwent biopsy and radical prostatectomy between October 1999 and January 2007 were included in the study. Pretreatment characteristics were used to identify predictors of pathological upgrading. Upgrading significance was established by comparing radical prostatectomy pathology between cases that were and were not upgraded.

RESULTS

A total of 134 patients (50%) were upgraded postoperatively to Gleason score 7 or higher. Preoperative prostate specific antigen greater than 5.0 ng/ml (p = 0.036), prostate weight 60 gm or less (p = 0.004) and more cancer volume at biopsy, defined by cancer involving greater than 5% of the biopsy tissue (p = 0.002), greater than 1 biopsy core (p <0.001) or greater than 10% of any core (p = 0.014), were associated with pathological upgrading. Upgraded patients were more likely to have extraprostatic extension and positive surgical margins at radical prostatectomy (p <0.001 and 0.001, respectively).

CONCLUSIONS

Prostate specific antigen, prostate volume and biopsy cancer volume predict clinically significant upgrading in patients diagnosed with Gleason score 6 disease. These parameters may be valuable in the pretreatment risk assessment of this patient population.

Does prostate biopsy Gleason score accurately express the biologic features of prostate cancer?

PURPOSE

To correlate Gleason grading in prostate biopsies with the final Gleason score in radical prostatectomy specimens, and to investigate predictors for concordance and preoperative undergrading.

MATERIALS AND METHODS

The charts of 303 patients who underwent radical retropubic prostatectomy between 1992 and 2002 were retrospectively reviewed. Prostate biopsy and surgical specimen Gleason scores and correlative clinical data were recorded, and a multivariate analysis model was applied.

RESULTS

Data were available in 293 cases (97%). The preoperative biopsy predicted the prostatectomy Gleason score accurately in 51% and undergraded them in 41% of the patients. Accuracy rates were significantly higher for Gleason scores 7-10 compared to low Gleason scores (2-4), concordance 90% and 6%, respectively (P < 0.01). Moreover, accuracy rates were higher in patients with prostate-specific antigen (PSA) higher than 10 ng/ml (85% vs. 40%; P < 0.01) and prostate glands smaller than 55 g (68% vs. 38%; P < 0.01). In 233 patients, the biopsy Gleason score did not include 4 or 5 components. Upgrading to 4 or 5 in 1 of the components was noted in 32 patients (14%). Multivariate analysis revealed that upgrading is associated with preoperative serum PSA (odds ratio 1.05; P < 0.05) and the percentage of positive cores in the biopsy (odds ratio 1.47; P < 0.001).

CONCLUSIONS

Biopsy Gleason scores of 2-4, low PSA, and a low percentage of positive cores in the biopsy can predict the biopsy driven biologically significant undergrading of 1 of the components of the Gleason score that may adversely affect therapeutic decisions.

Prognostic significance of Gleason score discrepancies between needle biopsy and radical prostatectomy

OBJECTIVES

Discordance between the Gleason score (GS) on needle biopsy (NB) and the GS of the radical prostatectomy (RP) specimen is a common finding. The objective of this study was to evaluate the prognostic significance of these discrepancies with respect to outcomes following RP.

METHODS

In the study, 6625 men treated by RP were categorized as having NB=RP (68.8%), NB<RP (25.0%) or NB>RP (6.2%) GS, and stratified for analyses into RP GS groups. The Kaplan-Meier method was used to analyze differences in biochemical recurrence-free survival (BRFS), and multivariate Cox analyses were performed to estimate the independent relative risk of progression associated with GS discrepancies.

RESULTS

Across multiple RP GS strata (3+4, 7, 8, 8-10), patients with a lower NB GS experienced significantly better BRFS than patients with equal NB and RP GS (all p<0.05). NB<RP GS was independently associated with better (pooled HR, 0.76, p=0.001) BRFS, within and across RP GS strata. Similarly, patients with NB>RP GS had poorer BRFS than patients with NB=RP GS across multiple RP GS strata (< or =3+3, 3+4, 7; all p<0.05). NB>RP GS was independently associated with worse (pooled HR, 1.91, p<0.001) BRFS probabilities, within and across RP GS strata.

CONCLUSIONS

Our data suggest that the GS of the NB adds additional prognostic value to the RP GS in a consistent manner that may be applicable to strategies of risk stratification and patient counseling after surgery.

Risk stratification of men with Gleason score 7 to 10 tumors by primary and secondary Gleason score: results from the SEARCH database

OBJECTIVES

Gleason score 4+3 prostate cancer is associated with worse clinicopathologic outcomes than is Gleason score 3+4. Whether the increased risk associated with Gleason score 4+3 disease is equivalent to that of Gleason score 4+4 or greater is unclear.

METHODS

We reviewed the data from two separate cohorts pulled from the Shared Equal Access Regional Cancer Hospital database. The first consisted of 374 men with biopsy Gleason score 3+4 or greater disease and the second of 636 men with radical prostatectomy (RP) Gleason score 3+4 or greater disease. We estimated the odds ratios of unfavorable surgical pathologic findings for the biopsy Gleason score categories using logistic regression analysis. Using a Cox proportional hazards regression model, we estimated the relative risk of biochemical progression associated with each biopsy and RP Gleason score category.

RESULTS

In the biopsy Gleason score cohort, a Gleason score of 4+3 was associated with an increased risk of extracapsular extension (P = 0.01) and seminal vesicle invasion (P <0.001) relative to a biopsy Gleason score of 3+4. A biopsy Gleason score of 4+3 was associated with a similar risk of adverse pathologic findings relative to a biopsy Gleason score of 4+4 or greater (all P >0.10), except for higher grade pathologic tumors among men with a biopsy Gleason score of 4+4 or more (P = 0.001). After adjusting for multiple clinical characteristics, a biopsy Gleason score of 4+3 was associated with an increased recurrence risk relative to a biopsy Gleason score of 3+4 (P = 0.001), but a similar progression risk as that for a biopsy Gleason score of 4+4 or more (P = 0.53). In the RP Gleason cohort, and after adjustment for multiple clinicopathologic features, an RP Gleason score of 4+3 was associated with increased progression risk relative to an RP Gleason score of 3+4 (P = 0.03), but similar progression risk as that for an RP Gleason score of 4+4 or more (P = 0.24).

CONCLUSIONS

In a multicenter database using pooled data from multiple pathologists, Gleason scores 4+3 and 4+4 or more exhibited similar clinicopathologic outcomes.

Reproducibility and reliability of tumor grading in urological neoplasms

Histopathologic tumor grading reflects the degree of differentiation of a given tumor and for most urological tumors grading is an important factor in predicting their biological aggressiveness. Consequently, the clinical management of tumor patients is often strongly influenced by the tumor grade, provided by pathologists. This implicates that an ideal grading system should not only be of high prognostic relevance, but also of high reproducibility among different pathologists. To this end individual histological grading systems have been developed for different tumor entities and even for a given tumor type several grading systems have been proposed. All of these grading systems possess an inherent degree of subjectivity and consequently, both intra- and interobserver variability exist. In this review, grading systems for the most frequent urological tumors (i.e. prostate cancer, renal cell carcinoma, and urothelial tumors) are mentioned and data on the reproducibility and reliability of the most commonly used grading systems are summarized.

Increasing the number of biopsies increases the concordance of Gleason scores of needle biopsies and prostatectomy specimens

PURPOSE

To determine the importance of increasing the number of biopsy cores to decrease the discrepancy of Gleason scores of needle biopsy and radical prostatectomy specimens.

MATERIALS AND METHODS

Between May 1998 and July 2005, 392 patients with clinically localized prostate cancer diagnosed by 18-gauge transrectal needle biopsy underwent radical prostatectomy. We categorized the cohort into 2 groups according to the number of the cores. Group 1 consisted of 206 patients diagnosed by extended biopsies (> or =10 cores, range 10-14, median 11). The remaining 186 patients who were diagnosed by sextant biopsies were categorized as being in group 2. Preoperative clinical variables, including patient age, digital rectal examination findings, serum prostate-specific antigen, and the number of cores positive for cancer the parameters, were assessed in both groups. The concordance of Gleason scores in both groups were analyzed by both individual Gleason scores and clinical subgroups of Gleason scores: 2-4 (well differentiated), 5-6 (moderately differentiated), 7 (intermediate), and 8-10 (poorly differentiated).

RESULTS

Needle biopsies revealed moderately differentiated tumors (Gleason 5-6) for the 2 groups (55.3% and 60.2%). Gleason scores of the needle biopsies were identical to that of the prostatectomy specimen in 116 (56.31%) and 76 cases (40.86%) for each group (kappa: 0.432 and 0.216 for each group, respectively). Gleason score of the needle biopsy differed by 1 grade in 56 (27.18%) and 84 cases (45.16%), and by > or =2 units in 34 (16.50%) and 26 cases (15.05%) for each group, respectively. Of the specimens, 34% were undergraded, and 10% were overgraded in group 1. These rates were 38% and 22% in group 2, respectively. A total of 70% in group 1 and 56% in group 2 remained in the same categorical group, 28% and 32% of the specimens were undergraded, and 4% and 12% were overgraded in groups 1 and 2, respectively. In group 1, the number of patients with Gleason scores of 2-4, 5-6, 7, and 8 were 9.7%, 55.3%, 21.4%, 13.6%, and 1.9%, 47.6%, 32%, 18.4%, graded by needle biopsies and radical prostatectomy specimens, respectively. However, in the sextant group, the change was the number of patients with Gleason scores of 2-4, 5-6, 7, and 8-10 was 5.4% 60.2%, 24.7%, and 9.7%, detected by needle biopsies, respectively. Radical prostatectomy specimens revealed the same Gleason categories in 4.3%, 41.9%, 38.7%, and 15.1%, respectively. There was no correlation between categorized prostate-specific antigen levels and concordance of the Gleason grade. Age and digital rectal examination results did not affect Gleason correlation.

CONCLUSIONS

We have shown that an extended biopsy scheme beyond its superior diagnostic capability also improves the concordance of Gleason scores of needle biopsies and radical prostatectomy specimens.

Upgrading and downgrading of prostate needle biopsy specimens: risk factors and clinical implications

OBJECTIVES

The prostate biopsy Gleason grade frequently differs from the radical prostatectomy (RP) grade. Given the critical role that needle biopsy plays in treatment decisions, we sought to determine the risk factors for upgrading and downgrading the prostate biopsy specimen.

METHODS

We determined the significant predictors of upgrading (worse RP grade than biopsy grade) and downgrading (better RP grade than biopsy grade) among 1113 men treated with RP from 1996 to 2005 within the Shared Equal Access Regional Cancer Hospital (SEARCH) database who had undergone at least sextant biopsy. The Gleason sum was examined as a categorical variable of 2 to 6, 3+4, and 4+3 or greater.

RESULTS

Overall, the disease of 299 men (27%) was upgraded and 123 (11%) was downgraded, and 691 men (62%) had identical biopsy and pathologic Gleason sum groups. Upgrading was associated with adverse pathologic features (P < or = 0.001) and the risk of biochemical progression (P = 0.001). Downgrading was associated with more favorable pathologic features (P < or = 0.01) and a decreased risk of progression (P = 0.04). On multivariate analysis, greater prostate-specific antigen levels (P < 0.001), more biopsy cores with cancer (P = 0.001), and obesity (P = 0.003) were all significantly and positively associated with upgrading. In contrast, biopsy Gleason sum 3+4 (P = 0.001) and obtaining eight or more biopsy cores (P = 0.01) were associated with a lower likelihood of upgrading.

CONCLUSIONS

Men whose disease was upgraded were at a greater risk of adverse pathologic features and biochemical progression. Men with "high-risk" cancer (greater prostate-specific antigen levels, more positive cores, and obese) were more likely to have their disease category upgraded, and obtaining more biopsy cores reduced the likelihood of upgrading.

Clinical impact of second pathology opinion: A longitudinal study of central genitourinary pathology review before prostate brachytherapy

PURPOSE

To evaluate the clinical impact of pathology review before prostate brachytherapy.

METHODS AND MATERIALS

Original and reviewing pathologists' reports were retrospectively collected from 1323 men treated with prostate brachytherapy between July 1998 and October 2005 at one institution. Statistical analysis was performed pre- and post-January 2002. The clinical impact of pathology review was evaluated.

RESULTS

Gleason Score (GS) change (GS(Delta)) occurred in 25.2% (334) of cases; GS increased in 21.6%, decreased in 2.4%, and diagnosed malignancy in 1.2% of cases. Post-2002, concordance in attributed GS improved, with GS(Delta) of 31.9-20.6%, respectively (p<0.001), and a reduction in the average GS(Delta) (p<0.001). The clinical impact was substantial with management changing in 14.8% of cases.

CONCLUSION

Concordance between the original and reviewing pathologists' GS has improved during the study period. Nevertheless, discordance persists in one of five cases. Pathology review remains essential, if treatment decisions hinge on GS.

Percentage of Gleason pattern 4 and 5 predicts survival after radical prostatectomy

BACKGROUND

Morphologic and clinical heterogeneity within tumor grades is well recognized in prostate cancer. The objective of the current study was to determine whether the combined percentage of Gleason patterns 4 and 5 in radical prostatectomy specimens is an independent predictor of cancer-specific survival in prostate cancer patients.

METHODS

The radical prostatectomy specimens were analyzed from 504 consecutive prostate cancer patients who were treated at Indiana University Medical Center between 1990 and 1998. Various clinical and pathologic characteristics were analyzed.

RESULTS

A higher combined percentage of Gleason patterns 4 and 5 was associated with older age, higher preoperative serum prostate-specific antigen level, higher pathologic stage, positive surgical margins, extraprostatic extension of tumor, higher Gleason score, perineural invasion, and lymph node metastasis. In the multivariate Cox regression model, the combined percentage of Gleason patterns 4 and 5 was found to be an independent predictor of cancer-specific survival (P = .04).

CONCLUSIONS

The combined percentage of Gleason patterns 4 and 5 is a powerful predictor of prostate cancer-specific survival. Assessment of high-grade cancer amounts may allow for better stratification of patients into appropriate prognostic groups and treatment protocols.

The significance of modified Gleason grading of prostatic carcinoma in biopsy and radical prostatectomy specimens

At an International Society of Urological Pathology consensus conference in 2005, the Gleason grading system for prostatic carcinoma underwent its first major revision. Gleason pattern 4 now includes most cribriform patterns and also fused and poorly formed glands. Our aims were to compare the grade distributions and assess the agreement between biopsy and radical prostatectomy specimens for the modified and conventional Gleason grading. More than 3,000 radical prostatectomy (RP), needle biopsies (NB) and transurethral resection specimens were assigned modified Gleason score (GS). In NB, modified GS 3 + 3 = 6 and 3 + 4 = 7a were almost equally common, while in RP, 3 + 4 = 7a was most common followed by 4 + 3 = 7b. After application of the modified GS on NB, a substantial shift in GS distribution occurred: The proportion of GS 6 and 7 were 48 and 26%, respectively, with conventional Gleason grading as compared to 22 and 68%, respectively, with modified grading. In 368 men, the agreement between NB and RP with a modified GS 6, 7a, 7b and 8-10 in NB was 28, 88, 68 and 64-100%, respectively. The overall agreement improved from 58 to 72% (p < 0.001) compared to conventional GS. The higher agreement with modified Gleason grading may facilitate therapeutic decisions.

Prostate Cancers Scored as Gleason 6 on Prostate Biopsy are Frequently Gleason 7 Tumors at Radical Prostatectomy: Implication on Outcome

PURPOSE

Differentiation between Gleason score 6 and 7 in prostate biopsy is important for treatment decision making. Nevertheless, under grading errors compared with the actual pathological grade at radical prostatectomy are common. We compared the characteristics and outcomes of tumors that were scored 6 on prostate biopsy but were 7 on subsequent radical prostatectomy pathological evaluation to those in tumors with a consistent rating of Gleason score 6 or 7 at biopsy and surgery.

MATERIALS AND METHODS

We performed a retrospective database analysis from our referral center (1989 to 2004). We compared pre-prostatectomy characteristics, radical prostatectomy pathological features and the post-radical prostatectomy prostate specific antigen failure rate, defined as any 2 consecutive detectable prostate specific antigen measurements, in 3 subgroups of patients, including 156 with matched Gleason score 6 in the prostate biopsy and radical prostatectomy, 205 with upgraded Gleason score 6/7, that is prostate biopsy Gleason score 6 and radical prostatectomy Gleason score 7, and 412 with matched Gleason score 7 in the prostate biopsy and radical prostatectomy.

RESULTS

Radical prostatectomy Gleason score matched the prostate biopsy score in 38.2% of biopsy Gleason score 6 and 81.4% of biopsy Gleason score 7 cases. Higher prostate specific antigen was associated and an increased percent of cancer in the prostate biopsy was predictive of discordance between the prostate biopsy and radical prostatectomy Gleason scores (p <0.001). Margin (p = 0.0075) or seminal vesicle involvement (p = 0.0002), cancer volume (p <0.001) and the prostate specific antigen failures rate (p = 0.014) were significantly higher in under graded Gleason score 7 cancer compared to those in matched Gleason score 6 cases. However, they were comparable to those with a matched Gleason score 7 tumor grade (p = 0.66).

CONCLUSIONS

Almost half of tumors graded Gleason score 6 at biopsy are Gleason score 7 at surgery. Upgraded Gleason score 6 to 7 tumors have outcomes similar to those of genuine Gleason score 7 cancer. For prostate biopsy Gleason score 6 tumors clinicians should consider the overall likelihood of tumor upgrading as well as specific patient characteristics, such as prostate specific antigen and the percent of tumor in the prostate biopsy, when contemplating treatments that are optimized for low grade tumors, including watchful waiting or brachytherapy.

Surgical pathology--second reviews, institutional reviews, audits, and correlations: what's out there? Error or diagnostic variation?

CONTEXT

A variety of methodologies have been used to report error rates in surgical pathology within the peer-reviewed medical literature. The media has selectively and superficially reported these error rates creating a climate of disinformation between physicians and the public.

OBJECTIVES

To review the medical literature on diagnostic error in surgical pathology and summarize and compare these data with selected reports in the print and broadcast media.

DESIGN

A search of the medical literature from the National Library of Medicine database using the heading "Error and Pathology Diagnosis."

RESULTS

Three thousand nine hundred ninety-two citations were found, of which 83 directly measured in some manner errors in surgical and cytopathology. Major error rates ranged from 1.5% to 5.7% globally for institutional consults. Error rates were less, 0.26% to 1.2% for global in-house prospective review and 4.0% for in-house and retrospective blinded review. Error rates also varied by anatomic site: skin, institutional consult, 1.4%; prostate, institutional consult, 0.5%; and thyroid, institutional consult, 7.0%. Error rates reported in citations used by the Wall Street Journal were as follows: prostate, Gleason score changed by 1 point, 44% and resultant change in treatment for prostate cancer, 10%; for breast, altered lumpectomy or mastectomy plan, 8%; and diagnosis changed for thyroid lesions, 18%. Errors in second opinion on breast lesions (single pathologist author for the study) fall within the range of global reviews. Errors for second opinions on prostate cancer were principally 81% upgrades in Gleason score for prostate core needle biopsies. However, this resulted in an upgrade of patient risk category in only 10.8% of patients. Data for the article on change in diagnosis of thyroid lesions were incomplete. There appeared to be 3 significant diagnostic errors (4.5%).

CONCLUSIONS

Pathology is not immune to the power of the media to create concern about accuracy of diagnosis in surgical pathology and cytopathology. Detailed analysis of the medical literature cited by the media determines that painting the big picture and hitting the highlights can be profoundly misleading.

Should Men with Serum Prostate-Specific Antigen ≤4 ng/ml and Normal Digital Rectal Examination Undergo a Prostate Biopsy?

The clinical significance of a prostate cancer (PCa) cannot be determined solely by tumor volume (< or =0.5 cm(3)), as small tumors of higher Gleason grade and tumors occurring in younger men may become clinically significant even though the initial volume at diagnosis is small. A certain number of these minimal cancers are likely to remain clinically insignificant; however, it is unpredictable how many can progress beyond the curable stage by the time there is a rise in serum prostate-specific antigen (PSA) values. Compared to clinically detected PCa, PCa detected exclusively by PSA screening (clinical stage T1c) are less likely to be advanced but no more likely to be insignificant in terms of volume, pathologic stage, and Gleason pattern. Only 10-15% of PSA-detected cancers have the features of PCa found at autopsy or in cystoprostatectomy specimens. Actually, 25-30% of PCa are detected with PSA values between 2.5 and 4 ng/ml, and most of these cancers are clinically significant. Evidence from both retrospective and longitudinal studies has shown that the risk of a PCa is dependent on the patient's age and the initial serum PSA. This allows an individualized approach to PCa screening programs, and PSA cutoff values for biopsy indication may be lowered in selected patients.

Increased accuracy of biopsy Gleason score obtained by extended needle biopsy

PURPOSE

Accurate tumor grading is critical for adequate prostate cancer treatment. Nonetheless, the Gleason score of standard sextant biopsy correctly predicts the Gleason score of the radical prostatectomy specimen in about 50% of cases. We investigated if extended needle biopsy could improve biopsy Gleason score accuracy.

MATERIALS AND METHODS

Laparoscopic transperitoneal radical prostatectomy was performed in 135 patients. Prostate cancer was diagnosed in 89 cases by standard sextant transrectal (6 to 8 cores) biopsy and in 46 by extended needle (12 core transperineal under transrectal guidance) biopsy. Preoperative evaluation included digital rectal examination, prostatic specific antigen measurement, transrectal ultrasonography and endorectal coil magnetic resonance imaging in all patients. All biopsy and prostatectomy specimens were reviewed by a single pathologist.

RESULTS

Clinical characteristics were similar in the 2 groups. The concordance between prostate biopsy and radical prostatectomy Gleason score was 32 of 46 cases (70%) and 44 of 89 (49%) for 12 core and standard transrectal biopsy, respectively (z test p = 0.0127). Biopsy under grading was found in 11 of 46 cases (24%) and 35 of 89 (39%) (z test p = 0.0366), and biopsy over grading was found in 3 of 46 (6%) and 10 of 89 (11%) (z test p = 0.1894) with 12 core and standard transrectal biopsy, respectively. Primary Gleason pattern was predicted exactly by biopsy in 40 of 46 cases (87%) and 56 of 89 (63%) with 12 core and standard sextant biopsy, respectively (z test p = 0.0018).

CONCLUSIONS

Extended needle biopsy significantly increases the accuracy of biopsy Gleason score for assessing final prostate cancer grade.

A study of Gleason score interpretation in different groups of UK pathologists; techniques for improving reproducibility

AIMS

To test the effectiveness of a teaching resource (a decision tree with diagnostic criteria based on published literature) in improving the proficiency of Gleason grading of prostatic cancer by general pathologists.

METHODS

A decision tree with diagnostic criteria was developed by a panel of urological pathologists during a reproducibility study. Twenty-four general histopathologists tested this teaching resource. Twenty slides were selected to include a range of Gleason score groups 2-4, 5-6, 7 and 8-10. Interobserver agreement was studied before and after a presentation of the decision tree and criteria. The results were compared with those of the panel of urological pathologists.

RESULTS

Before the teaching session, 83% of readings agreed within +/- 1 of the panel's consensus scores. Interobserver agreement was low (kappa = 0.33) compared with that for the panel (kappa = 0.62). After the presentation, 90% of readings agreed within +/- 1 of the panel's consensus scores and interobserver agreement amongst the pathologists increased to kappa = 0.41. Most improvement in agreement was seen for the Gleason score group 5-6.

CONCLUSIONS

The lower level of agreement among general pathologists highlights the need to improve observer reproducibility. Improvement associated with a single training session is likely to be limited. Additional strategies include external quality assurance and second opinion within cancer networks.

E-cadherin polymorphisms and haplotypes influence risk for prostate cancer

BACKGROUND

The E-cadherin (CDH1) gene has been implicated in prostate cancer (PCA) risk, however, the exact mechanism is unknown. Several polymorphisms, such as the C/A variant -160 base pairs from the transcription start site, in the CDH1 gene promoter region have been associated with cancer risk, mainly in European descent populations.

METHODS

We screened the entire coding region and 3.0 kilobases of the CDH1 promoter for polymorphisms in 48 African Americans using dHPLC. Twenty-one (21) polymorphisms were observed. Four polymorphisms, including -160C/A, were genotyped in a genetic association study using incident PCA cases (N = 427) and unaffected controls (N = 337) of similar age from three different ethnic groups consisting of African Americans, Jamaicans, and European Americans.

RESULTS

We observed a significantly higher frequency of the -160A allele among European American PCA patients (27.5%) compared to the control group (19.7%) (P = 0.04). More importantly, among men of European ancestry under the age of 65 who possess the -160 A allele there was over three times increased risk for prostate cancer (P = 0.05). Also, the AACT haplotype bearing the -160A allele was significantly associated with PCA in European Americans (P = 0.04).

CONCLUSIONS

Our data indicate that CDH1 likely is a low-penetrant PCA susceptibility gene, however, population differences in linkage disequilibrium within the CDH1 gene region may influence the effect of susceptibility alleles such as -160A.