Clinical Usefulness of Total Length of Gleason Pattern 4 on Biopsy in Men with Grade Group 2 Prostate Cancer

Amount of Gleason Pattern 3 Is Not Predictive of Risk in Grade Group 2-4 Prostate Cancer

We investigated whether total Gleason pattern 3 or the proportion of Gleason pattern 4 on biopsy is a significant predictor of adverse pathology. Our findings suggest that quantifying the amount rather than the proportion of Gleason pattern 4 would improve grade group assignment for decision-making in localized prostate cancer.

The oncologic risk of magnetic resonance imaging-targeted and systematic cores in patients treated with radical prostatectomy

BACKGROUND

Magnetic resonance imaging (MRI)-targeted prostate biopsy (MRI-biopsy) detects high-Grade Group (GG) prostate cancers not identified by systematic biopsy (S-biopsy). However, questions have been raised whether cancers detected by MRI-biopsy and S-biopsy, grade-for-grade, are of equivalent oncologic risk. The authors evaluated the relative oncologic risk of GG diagnosed by S-biopsy and MRI-biopsy.

METHODS

This was a retrospective analysis of all patients who had both MRI-biopsy and S-biopsy and underwent with prostatectomy (2014-2022) at Memorial Sloan Kettering Cancer Center. Three logistic regression models were used with adverse pathology as the primary outcome (primary pattern 4, any pattern 5, seminal vesicle invasion, or lymph node involvement). The first model included the presurgery prostate-specific antigen level, the number of positive and negative S-biopsy cores, S-biopsy GG, and MRI-biopsy GG. The second model excluded MRI-biopsy GG to obtain the average risk based on S-biopsy GG. The third model excluded S-biopsy GG to obtain the risk based on MRI-biopsy GG. A secondary analysis using Cox regression evaluated the 12-month risk of biochemical recurrence.

RESULTS

In total, 991 patients were identified, including 359 (36%) who had adverse pathology. MRI-biopsy GG influenced oncologic risk compared with S-biopsy GG alone (p < .001). However, if grade was discordant between biopsies, then the risk was intermediate between grades. For example, the average risk of advanced pathology for patients who had GG2 and GG3 on S-biopsy was 19% and 66%, respectively, but the average risk was 47% for patients who had GG2 on S-biopsy and patients who had GG3 on MRI-biopsy. The equivalent estimates for 12-month biochemical recurrence were 5.8%, 15%, and 10%, respectively.

CONCLUSIONS

The current findings cast doubt on the practice of defining risk group based on the highest GG. Because treatment algorithms depend fundamentally on GG, further research is urgently required to assess the oncologic risk of prostate tumors depending on detection technique.

PLAIN LANGUAGE SUMMARY

Using magnetic resonance imaging (MRI) to help diagnose prostate cancer can help identify more high-grade cancers than using a systematic template biopsy alone. However, we do not know if high-grade cancers diagnosed with the help of an MRI are as dangerous to the patient as high-grade cancers diagnosed with a systematic biopsy. We examined all of our patients who had an MRI biopsy and a systematic biopsy and then had their prostates removed to find out if these patients had risk factors and signs of aggressive cancer (cancer that spread outside the prostate or was very high grade). We found that, if there was a difference in grade between the systematic biopsy and the MRI-targeted biopsy, the risk of aggressive cancer was between the two grades.

Quantification of Gleason Pattern 4 at MRI-Guided Biopsy to Predict Adverse Pathology at Radical Prostatectomy in Intermediate-Risk Prostate Cancer Patients

BACKGROUND

Data on Gleason pattern 4 (GP4) amount in biopsy tissue is important for prostate cancer (PC) risk assessment. We aim to investigate which GP4 quantification method predicts adverse pathology (AP) at radical prostatectomy (RP) the best in men diagnosed with intermediate-risk (IR) PC at magnetic resonance imaging (MRI)-guided biopsy.

METHODS

We retrospectively included 123 patients diagnosed with IR PC (prostate-specific antigen <20 ng/mL, grade group (GG) 2 or 3, no iT3 on MRI) at MRI-guided biopsy, who underwent RP. Twelve GP4 amount-related parameters were developed, based on GP4 quantification method (absolute, relative to core, or cancer length) and site (overall, targeted, systematic biopsy, or worst specimen). Additionally, we calculated PV×GP4 (prostate volume × GP4 relative to core length in overall biopsy), aiming to represent the total GP4 volume in the prostate. The associations of GP4 with AP (GG ≥ 4, ≥pT3a, or pN1) were investigated.

RESULTS

AP was reported in 39 (31.7%) of patients. GP4 relative to cancer length was not associated with AP. Of the 12 parameters, the highest ROC AUC value was seen for GP4 relative to core length in overall biopsy (0.65). an even higher AUC value was noted for PV × GP4 (0.67), with a negative predictive value of 82.8% at the optimal threshold.

CONCLUSIONS

The lack of an association of GP4 relative to cancer length with AP, contrasted with the better performance of other parameters, indicates directions for future research on PC risk stratification to accurately identify patients who may not require immediate treatment. Incorporating formulas aimed at GP4 volume assessment may lead to obtaining models with the best discrimination ability.

Active surveillance should not be routinely considered in ISUP grade group 2 prostate cancer

Active surveillance has been proposed as a therapeutic option in selected intermediate risk patients with biopsy grade group 2 prostate cancer. However, its oncologic safety in this setting is debated. Therefore, we conducted a non-systematic literature research of contemporary surveillance protocols including patients with grade group 2 disease to collect the most recent evidence in this setting. Although no randomized controlled trial compared curative-intent treatments, namely radical prostatectomy and radiotherapy vs. active surveillance in patients with grade group 2 disease, surgery is associated with a benefit in terms of disease control and survival when compared to expectant management in the intermediate risk setting. Patients with grade group 2 on active surveillance were at higher risk of disease progression and treatment compared to their grade group 1 counterparts. Up to 50% of those patients were eventually treated at 5 years, and the metastases-free survival rate was as low as 85% at 15-years. When considering low- and intermediate risk patients treated with radical prostatectomy, grade group 2 was one of the strongest predictors of grade upgrading and adverse features. Available data is insufficient to support the oncologic safety of active surveillance in all men with grade group 2 prostate cancer. Therefore, those patients should be counselled regarding the oncologic efficacy of upfront active treatment modalities and the lack of robust long-term data supporting the safety of active surveillance in this setting.

Outcomes of Grade Group 2 and 3 Prostate Cancer on Initial Versus Confirmatory Biopsy: Implications for Active Surveillance

BACKGROUND

Active surveillance (AS) is recommended as the preferred treatment for men with low-risk disease. In order to optimize risk stratification and exclude undiagnosed higher-grade disease, most AS protocols recommend a confirmatory biopsy.

OBJECTIVE

We aimed to compare outcomes among men with grade group (GG) 2/3 prostate cancer on initial biopsy with those among men whose disease was initially GG1 but was upgraded to GG2/3 on confirmatory biopsy.

DESIGN, SETTING, AND PARTICIPANTS

We reviewed patients undergoing radical prostatectomy (RP) in two cohorts: "immediate RP group," with GG2/3 cancer on diagnostic biopsy, and "AS group," with GG1 cancer on initial biopsy that was upgraded to GG2/3 on confirmatory biopsy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Probabilities of biochemical recurrence (BCR) and salvage therapy were determined using multivariable Cox regression models with risk adjustment. Risks of adverse pathology at RP were also compared using logistic regression.

RESULTS AND LIMITATIONS

The immediate RP group comprised 4009 patients and the AS group comprised 321 patients. The AS group had lower adjusted rates of adverse pathology (27% vs 35%, p = 0.003). BCR rates were lower in the AS group, although this did not reach conventional significance (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.50-1.06, p = 0.10) compared with the immediate RP group. Risk-adjusted 1- and 5-yr BCR rates were 4.6% (95% CI 3.0-6.5%) and 10.4% (95% CI 6.9-14%), respectively, for the AS group compared with 6.3% (95% CI 5.6-7.0%) and 20% (95% CI 19-22%), respectively, in the immediate RP group. A nonsignificant association was observed for salvage treatment-free survival favoring the AS group (HR 0.67, 95% CI 0.42, 1.06, p = 0.087).

CONCLUSIONS

We found that men with GG1 cancer who were upgraded on confirmatory biopsy tend to have less aggressive disease than men with the same grade found at initial biopsy. These results must be confirmed in larger series before recommendations can be made regarding a more conservative approach in men with upgraded pathology on surveillance biopsy.

PATIENT SUMMARY

We studied men with low-risk prostate cancer who were initially eligible for active surveillance but presented with more aggressive cancer on confirmatory biopsy. We found that outcomes for these men were better than the outcomes for those diagnosed initially with more serious cancer.

Blood Prostate-specific Antigen by Volume of Benign, Gleason Pattern 3 and 4 Prostate Tissue

OBJECTIVE

To evaluate how blood levels of prostate-specific antigen (PSA) relate to prostate volume of benign tissue, Gleason pattern 3 (GP3) and Gleason pattern 4 (GP4) cancer.

METHODS

The cohort included 2209 consecutive men undergoing radical prostatectomy at 2 academic institutions with pT2N0, Grade Group 1-4 prostate cancer and an undetectable postoperative PSA. Volume of benign, GP3, and GP4 were estimated. The primary analysis evaluated the association between PSA and volume of each type of tissue using multivariable linear regression. R2, a measure of explained variation, was calculated using a multivariable model.

RESULTS

Estimated contribution to PSA was 0.04/0.06 ng/mL/cc for benign, 0.08/0.14 ng/mL/cc for GP3, and 0.62/0.80 ng/ml/cc for GP4 for the 2 independent cohorts, respectively. GP4 was associated with 6 to 8-fold more PSA per cc compared to GP3 and 15-fold higher compared to benign tissue. We did not observe a difference between PSA per cc for GP3 vs. benign tissue (P = 0.2). R2 decreased only slightly when removing age (0.006/0.018), volume of benign tissue (0.051/0.054) or GP3 (0.014/0.023) from the model. When GP4 was removed, R2 decreased 0.051/0.310. PSA density (PSA divided by prostate volume) was associated with volume of GP4 but not GP3, after adjustment for benign volume.

CONCLUSION

Gleason pattern 4 cancer contributes considerably more to PSA and PSA density per unit volume compared to GP3 and benign tissue. Contributions from GP3 and benign are similar. Further research should examine the utility of determining clinical management recommendations by absolute volume of GP4 rather than the ratio of GP3 to GP4.

The highest percentage of Gleason Pattern 4 is a predictor in intermediate-risk prostate cancer

Objectives

This study aims to clarify the clinicopathological significance of several novel pathological markers, including the percentage of Gleason pattern 4 and small/non-small cribriform pattern, in intermediate-risk Gleason score 3 + 4 = 7 prostate cancer.

Subjects and Methods

Two-hundred and twenty-eight patients with Gleason score 3 + 4 = 7 intermediate-risk prostate cancer who underwent radical prostatectomy between 2009 and 2019 at our institute were selected. Preoperative clinicopathological characteristics, including serum prostate-specific antigen level, clinical T stage, percentage of cancer-positive cores at biopsy, small/non-small cribriform pattern, the highest percentage of Gleason pattern 4, the total length of Gleason pattern 4 and percentage of Gleason score 7 cores were examined in univariate/multivariate logistic regression analysis to determine their predictive value for postoperative adverse pathological findings, defined as an upgrade to Gleason score 4 + 3 = 7 or higher, pN1 or pT3b disease.

Results

Fifty-four cases (23.7%) showed adverse pathological findings. Although a non-small cribriform pattern, highest Gleason pattern 4 percentage and total length of Gleason pattern 4 were predictive of adverse pathological findings in univariate analysis, only the highest Gleason pattern 4 percentage was an independent predictive factor in multivariate analysis (odds ratio: 1.610; 95% confidence interval: 1.260-2.070; P = 0.0002).

Conclusion

The highest Gleason pattern 4 percentage was a potent predictive parameter for Gleason score 3 + 4 = 7 intermediate-risk prostate cancer and should be considered in the risk classification scheme for prostate cancer.

Genitourinary tumors

Memorial Sloan Kettering Cancer Center (MSK) has made many notable contributions to the scientific understanding and care of patients with common urologic cancers. Many of the advances represented paradigm shifts in management and established new standards of care. This review highlights the surgical procedures and treatment strategies originated and pioneered by urologic surgeons and colleagues at MSK during the past 50 years.

Prediction of Adverse Pathology at Radical Prostatectomy in Grade Group 2 and 3 Prostate Biopsies Using Machine Learning

PURPOSE

There is ongoing clinical need to improve estimates of disease outcome in prostate cancer. Machine learning (ML) approaches to pathologic diagnosis and prognosis are a promising and increasingly used strategy. In this study, we use an ML algorithm for prediction of adverse outcomes at radical prostatectomy (RP) using whole-slide images (WSIs) of prostate biopsies with Grade Group (GG) 2 or 3 disease.

METHODS

We performed a retrospective review of prostate biopsies collected at our institution which had corresponding RP, GG 2 or 3 disease one or more cores, and no biopsies with higher than GG 3 disease. A hematoxylin and eosin-stained core needle biopsy from each site with GG 2 or 3 disease was scanned and used as the sole input for the algorithm. The ML pipeline had three phases: image preprocessing, feature extraction, and adverse outcome prediction. First, patches were extracted from each biopsy scan. Subsequently, the pre-trained Visual Geometry Group-16 convolutional neural network was used for feature extraction. A representative feature vector was then used as input to an Extreme Gradient Boosting classifier for predicting the binary adverse outcome. We subsequently assessed patient clinical risk using CAPRA score for comparison with the ML pipeline results.

RESULTS

The data set included 361 WSIs from 107 patients (56 with adverse pathology at RP). The area under the receiver operating characteristic curves for the ML classification were 0.72 (95% CI, 0.62 to 0.81), 0.65 (95% CI, 0.53 to 0.79) and 0.89 (95% CI, 0.79 to 1.00) for the entire cohort, and GG 2 and GG 3 patients, respectively, similar to the performance of the CAPRA clinical risk assessment.

CONCLUSION

We provide evidence for the potential of ML algorithms to use WSIs of needle core prostate biopsies to estimate clinically relevant prostate cancer outcomes.

Oncologic Outcomes of Total Length Gleason Pattern 4 on Biopsy in Men with Grade Group 2 Prostate Cancer

PURPOSE

Gleason Score 7 prostate cancer comprises a wide spectrum of disease risk, and precise substratification is paramount. Our group previously demonstrated that the total length of Gleason pattern (GP) 4 is a better predictor than %GP4 for adverse pathological outcomes at radical prostatectomy. We aimed to determine the association of GP4 length on prostate biopsy with post-prostatectomy oncologic outcomes.

MATERIALS AND METHODS

We compared 4 GP4 quantification methods-including maximum %GP4 in any single core, overall %GP4, total length GP4 (mm) across all cores and length GP4 (mm) in the highest volume core-for prediction of biochemical recurrence-free survival after radical prostatectomy using multivariable Cox proportional hazards regression.

RESULTS

A total of 457 men with grade group 2 prostate cancer on biopsy subsequently underwent radical prostatectomy. The 3-year biochemical recurrence-free survival probability was 85% (95% CI 81-88). On multivariable analysis, all 4 GP4 quantification methods were associated with biochemical recurrence-maximum %GP4 (HR=1.30; 95% CI 1.07-1.59; p=0.009), overall %GP4 (HR=1.61; 95% CI 1.21-2.15; p=0.001), total length GP4 (HR=2.48; 95% CI 1.36-4.52; p=0.003) and length GP4 in highest core (HR=1.32; 95% CI 1.11-1.57; p=0.001). However, we were unable to identify differences between methods of quantification with a relatively low event rate.

CONCLUSIONS

These findings support further studies on GP4 quantification in addition to the ratio of GP3 and GP4 to classify prostate cancer risk. Research should also be conducted on whether GP4 quantification could provide a surrogate endpoint for disease progression for trials in active surveillance.

Association between Incidental Pelvic Inflammation and Aggressive Prostate Cancer

The impact of pelvic inflammation on prostate cancer (PCa) biology and aggressive phenotype has never been studied. Our study objective was to evaluate the role of pelvic inflammation on PCa aggressiveness and its association with clinical outcomes in patients following radical prostatectomy (RP). This study has been conducted on a retrospective single-institutional consecutive cohort of 2278 patients who underwent robot-assisted laparoscopic prostatectomy (RALP) between 01/2013 and 10/2019. Data from 2085 patients were analyzed to study the association between pelvic inflammation and adverse pathology (AP), defined as Gleason Grade Group (GGG) > 2 and ≥ pT3 stage, at resection. In a subset of 1997 patients, the association between pelvic inflammation and biochemical recurrence (BCR) was studied. Alteration in tumor transcriptome and inflammatory markers in patients with and without pelvic inflammation were studied using microarray analysis, immunohistochemistry, and culture supernatants derived from inflamed sites used in functional assays. Changes in blood inflammatory markers in the study cohort were analyzed by O-link. In univariate analyses, pelvic inflammation emerged as a significant predictor of AP. Multivariate cox proportional-hazards regression analyses showed that high pelvic inflammation with pT3 stage and positive surgical margins significantly affected the time to BCR (p ≤ 0.05). PCa patients with high inflammation had elevated levels of pro-inflammatory cytokines in their tissues and in blood. Genes involved in epithelial-to-mesenchymal transition (EMT) and DNA damage response were upregulated in patients with pelvic inflammation. Attenuation of STAT and IL-6 signaling decreased tumor driving properties of conditioned medium from inflamed sites. Pelvic inflammation exacerbates the progression of prostate cancer and drives an aggressive phenotype.

Active surveillance in favorable intermediate risk prostate cancer: outstanding questions and controversies

PURPOSE OF REVIEW

Active surveillance has become the preferred management strategy for patients with low risk prostate cancer, but it is unclear if active surveillance can be safely extended to favorable intermediate risk (FIR) prostate cancer patients. Furthermore, defining a favorable intermediate risk prostate cancer population safe for active surveillance remains elusive due to paucity of high-level data in this population. This article serves to review relevant data, particularly the safety of active surveillance in grade group 2 patients, and what tools are available to aid in selecting a favorable subset of intermediate risk patients.

RECENT FINDINGS

Active surveillance studies with long-term data appear to report worsened survival outcomes in intermediate risk patients when compared to those undergoing definitive treatment, but there exists a subset of intermediate risk patients with nearly equivalent outcomes to low risk patients on active surveillance. Tools such as percentage and total length of Gleason pattern 4, tumor volume, prostate specific antigen density, magnetic resonance imaging, and genomic modifiers may help to select a favorable subset of intermediate risk prostate cancer appropriate for active surveillance.

SUMMARY

Active surveillance is a viable strategy in select patients with low volume group grade 2 (GG2) prostate cancer. Prospective and retrospective data in the FIR population appear to be mostly favorable in regards to survival outcomes, but there exists some heterogeneity with respect to long-term outcomes in this patient population.

Histopathological Study of the Prostate Cancer Growth Patterns in Relation with the Grading Systems

Prostate adenocarcinomas are common lesions with a high incidence and variable prognosis, which can be assessed using tumor grading systems. In this study, we analyzed 329 prostate adenocarcinomas in relation to tumor variants, growth patterns, classical and updated grading systems. The study indicated statistical associations of atrophic, pseudohyperplastic and microcystic variants with low grading scores, the associations of glomeruloid, cribriform with or without necrosis and signet ring-like cell variants with high grading scores, and also of single growth patterns with intermediate scores, which supports the accordance and usefulness of existing grading systems for the identification of aggressive prostate tumor lesions.

Expression of Ganglioside Disialosyl Globopentaosyl Ceramide in Prostate Biopsy Specimens as a Predictive Marker for Recurrence after Radical Prostatectomy

Carbohydrate antigens are associated with carcinogenesis, cancer invasion, and metastasis and their expression reflect biological activities of various cancers. We previously reported that expression of disialosyl globopentaosyl ceramide (DSGb5), one of carbohydrate antigens, in radical prostatectomy specimens independently predicted biochemical recurrence (i.e., elevating serum prostate specific antigen without recurrent lesions in the image) after radical prostatectomy. However, it is important to evaluate the prognosis at the diagnosis. In this study we investigated DSGb5 expression in prostate biopsy specimens to develop a novel biomarker for providing appropriate management. Between 2005 and 2011, patients who underwent both prostate biopsy and radical prostatectomy in our institution were included. The median follow-up period was 88 months. DSGb5 expression was assessed by immunohistochemical staining and defined 116 patients as high DSGb5 expression (42 patients) or low DSGb5 expression (74 patients). High DSGb5 expression was significantly associated with lymphovascular invasion in radical prostatectomy specimens on both univariate and multivariable analyses (p = 0.028, 0.027). On multivariable analysis, Gleason Score in prostatectomy specimen, positive resection margin, and DSGb5 expression in the biopsy specimen were independently associated with biochemical recurrence-free survival following radical prostatectomy (p = 0.004, 0.008, 0.024). When targeting only patients with negative resection margin, DSGb5 expression was significantly associated with biochemical recurrence-free survival on both univariate and multivariable analyses (p = 0.006, 0.007). DSGb5 expression in prostate biopsy specimens is predictive of lymphovascular invasion and biochemical recurrence-free survival following radical prostatectomy. DSGb5 is a potential biomarker for preoperatively predicting oncological outcomes of prostate cancer.

Optimal Method for Reporting Prostate Cancer Grade in MRI-targeted Biopsies

When multiple cores are biopsied from a single magnetic resonance imaging (MRI)-targeted lesion, Gleason grade may be assigned for each core separately or for all cores of the lesion in aggregate. Because of the potential for disparate grades, an optimal method for pathology reporting MRI lesion grade awaits validation. We examined our institutional experience on the concordance of biopsy grade with subsequent radical prostatectomy (RP) grade of targeted lesions when grade is determined on individual versus aggregate core basis. For 317 patients (with 367 lesions) who underwent MRI-targeted biopsy followed by RP, targeted lesion grade was assigned as (1) global Grade Group (GG), aggregated positive cores; (2) highest GG (highest grade in single biopsy core); and (3) largest volume GG (grade in the core with longest cancer linear length). The 3 biopsy grades were compared (equivalence, upgrade, or downgrade) with the final grade of the lesion in the RP, using κ and weighted κ coefficients. The biopsy global, highest, and largest GGs were the same as the final RP GG in 73%, 68%, 62% cases, respectively (weighted κ: 0.77, 0.79, and 0.71). For cases where the targeted lesion biopsy grade scores differed from each other when assigned by global, highest, and largest GG, the concordance with the targeted lesion RP GG was 69%, 52%, 31% for biopsy global, highest, and largest GGs tumors (weighted κ: 0.65, 0.68, 0.59). Overall, global, highest, and largest GG of the targeted biopsy show substantial agreement with RP-targeted lesion GG, however targeted global GG yields slightly better agreement than either targeted highest or largest GG. This becomes more apparent in nearly one third of cases when each of the 3 targeted lesion level biopsy scores differ. These results support the use of global (aggregate) GG for reporting of MRI lesion-targeted biopsies, while further validations are awaited.

The 2019 Genitourinary Pathology Society (GUPS) White Paper on Contemporary Grading of Prostate Cancer

CONTEXT.—

Controversies and uncertainty persist in prostate cancer grading.

OBJECTIVE.—

To update grading recommendations.

DATA SOURCES.—

Critical review of the literature along with pathology and clinician surveys.

CONCLUSIONS.—

Percent Gleason pattern 4 (%GP4) is as follows: (1) report %GP4 in needle biopsy with Grade Groups (GrGp) 2 and 3, and in needle biopsy on other parts (jars) of lower grade in cases with at least 1 part showing Gleason score (GS) 4 + 4 = 8; and (2) report %GP4: less than 5% or less than 10% and 10% increments thereafter. Tertiary grade patterns are as follows: (1) replace "tertiary grade pattern" in radical prostatectomy (RP) with "minor tertiary pattern 5 (TP5)," and only use in RP with GrGp 2 or 3 with less than 5% Gleason pattern 5; and (2) minor TP5 is noted along with the GS, with the GrGp based on the GS. Global score and magnetic resonance imaging (MRI)-targeted biopsies are as follows: (1) when multiple undesignated cores are taken from a single MRI-targeted lesion, an overall grade for that lesion is given as if all the involved cores were one long core; and (2) if providing a global score, when different scores are found in the standard and the MRI-targeted biopsy, give a single global score (factoring both the systematic standard and the MRI-targeted positive cores). Grade Groups are as follows: (1) Grade Groups (GrGp) is the terminology adopted by major world organizations; and (2) retain GS 3 + 5 = 8 in GrGp 4. Cribriform carcinoma is as follows: (1) report the presence or absence of cribriform glands in biopsy and RP with Gleason pattern 4 carcinoma. Intraductal carcinoma (IDC-P) is as follows: (1) report IDC-P in biopsy and RP; (2) use criteria based on dense cribriform glands (>50% of the gland is composed of epithelium relative to luminal spaces) and/or solid nests and/or marked pleomorphism/necrosis; (3) it is not necessary to perform basal cell immunostains on biopsy and RP to identify IDC-P if the results would not change the overall (highest) GS/GrGp part per case; (4) do not include IDC-P in determining the final GS/GrGp on biopsy and/or RP; and (5) "atypical intraductal proliferation (AIP)" is preferred for an intraductal proliferation of prostatic secretory cells which shows a greater degree of architectural complexity and/or cytological atypia than typical high-grade prostatic intraepithelial neoplasia, yet falling short of the strict diagnostic threshold for IDC-P. Molecular testing is as follows: (1) Ki67 is not ready for routine clinical use; (2) additional studies of active surveillance cohorts are needed to establish the utility of PTEN in this setting; and (3) dedicated studies of RNA-based assays in active surveillance populations are needed to substantiate the utility of these expensive tests in this setting. Artificial intelligence and novel grading schema are as follows: (1) incorporating reactive stromal grade, percent GP4, minor tertiary GP5, and cribriform/intraductal carcinoma are not ready for adoption in current practice.

Extent of High-Grade Prostatic Adenocarcinoma in Multiparametric Magnetic Resonance Imaging-Targeted Biopsy Enhances Prediction of Pathologic Stage

CONTEXT.—

Multiparametric magnetic resonance imaging (mpMRI) of prostate with targeted biopsy has enhanced detection of high-grade prostatic adenocarcinoma (HG PCa). However, utility of amount of HG PCa (Gleason pattern 4/5) in mpMRI-targeted biopsies versus standard 12-core biopsies in predicting adverse outcomes on radical prostatectomy (RP) is unknown.

OBJECTIVE.—

To examine the utility of amount of HG PCa in mpMRI-targeted biopsies versus standard 12-core biopsies in predicting adverse RP outcomes.

DESIGN.—

We performed a retrospective review of prostate biopsies, which had corresponding RP, 1 or more mpMRI-targeted biopsy, and grade group 2 disease or higher. For the 169 cases identified, total millimeters of carcinoma and HG PCa, and longest length HG PCa in a single core were recorded for 12-core biopsies and each set of mpMRI-targeted biopsies. For RP specimens, Gleason grade, extraprostatic extension, seminal vesicle involvement, and lymph node metastasis were recorded. The main outcome studied was prostate-confined disease at RP. A logistic regression model was used to test which pre-RP variables related to this outcome.

RESULTS.—

Univariate analysis showed significant associations with adverse RP outcomes in 5 of 8 quantifiable variables; longest millimeter HG PCa in a single 12-core biopsy, highest grade group in any core, and total millimeter HG in mpMRI-targeted biopsies showed no statistical association (P = .54, P = .13, and P = .55, respectively). In multivariate analysis, total millimeter carcinoma in all cores, highest GrGrp in any core, and longest millimeter HG PCa in a single mpMRI-targeted core provided additional predictive value (P < .001, P = .004, and P = .03, respectively).

CONCLUSIONS.—

Quantitation of HG PCa in mpMRI-targeted biopsies provides additional value over 12-core biopsies alone in predicting nonorgan confined prostate cancer at RP. Linear millimeters of HG PCa in mpMRI-targeted biopsies is a significant parameter associated with higher pathologic stage and could be of value in risk models.

Comparative influence of cribriform growth and percent Gleason 4 in prostatic biopsies with Gleason 3+4 cancer

The International Society of Urological Pathology endorses specifying presence of cribriform architecture in Gleason (G)4 prostate cancer because of cribriform's aggressiveness. The relative effect of cribriform presence versus percentage G4 within grade group (GG)2 or 3 was uncertain. 194 men's biopsies with GG2 with or without cribriform (excluding glomeruloid from cribriform) and GG3 without cribriform (controls) from 4 years were reviewed. 173 cases had follow-up including 147 GG2 (15/147 or 10% had cribriform) and 26 GG3. Effects of total tumor specimen involvement, %Gleason 4, and cribriform were stratified into prostatectomy (n = 90), radiotherapy (n = 61), and watching waiting (n = 22) groups. Median follow-up duration was 3.32 years (range 1.90-6.18). Biochemical failures in the above 3 cohorts numbered 9 (9/90; 10%), 5 (5/61; 8%), and 13 (13/22; 59%) respectively. In all groups, (GG2+ GG3, n = 173), the HR for C pattern was 1.64. In GG2, cribriform presence (considering glomeruloid as non-cribriform) conferred a hazard ratio (HR) of 1.51 (p = 0.48). It was 1.38, excluding glomeruloid. In watchful waiting cohort only, presence of C conferred a HR of 2.62 (p = 0.086). All remaining comparisons including percent G4, remained not significant. Thus, only in WW group did cribriform pattern presence approach significance. Detection of differences otherwise was not feasible, probably because: 1) biochemical failure is too rare in GG2 cancer; 2) cribriform frequency was only 10% in GG2 (in current study), less than in higher-grade cancer. 3) Use of biopsy tissue is subject to sampling variation which may undersample cribriform pattern, though biopsy forms the basis of treatment decisions.

A Comparison of Genitourinary Society Pathology and International Society of Urological Pathology Prostate Cancer Guidelines

In 2019, the Genitourinary Pathology Society (GUPS) and International Society of Urological Pathology (ISUP) held their own consensus conferences on prostate cancer grading and reporting, with separately published manuscripts. The majority of GUPS and ISUP grading recommendations are compatible, but for some issues there is a lack of concordance or recommendations between the societies. As a result, both in practice and in research, these differences may manifest in difficulties when comparing pathology reports or data.

The 2019 International Society of Urological Pathology (ISUP) Consensus Conference on Grading of Prostatic Carcinoma

Five years after the last prostatic carcinoma grading consensus conference of the International Society of Urological Pathology (ISUP), accrual of new data and modification of clinical practice require an update of current pathologic grading guidelines. This manuscript summarizes the proceedings of the ISUP consensus meeting for grading of prostatic carcinoma held in September 2019, in Nice, France. Topics brought to consensus included the following: (1) approaches to reporting of Gleason patterns 4 and 5 quantities, and minor/tertiary patterns, (2) an agreement to report the presence of invasive cribriform carcinoma, (3) an agreement to incorporate intraductal carcinoma into grading, and (4) individual versus aggregate grading of systematic and multiparametric magnetic resonance imaging-targeted biopsies. Finally, developments in the field of artificial intelligence in the grading of prostatic carcinoma and future research perspectives were discussed.

Combination of total length of Gleason pattern 4 and number of Gleason score 3 + 4 = 7 cores detects similar outcome group to Gleason score 6 cancers among cases with ≥5% of Gleason pattern 4

Expanding the inclusion criteria for active prostate cancer surveillance to include cases with a Gleason score (GS) of 3 + 4 = 7 has been discussed. GS 3 + 4 = 7 cases with a percentage of Gleason pattern 4 (%GP4) <5% were shown to be associated with similar outcomes with those of GS 6 cases. We examined the clinicopathological significance of %GP4 ≥5% with a limited amount of GP4. A total of 315 radical prostatectomy cases with GS 6 or 3 + 4 = 7 in a prior biopsy, were reviewed. The cases with the highest %GP4 ≥5% were subcategorized using the total length of GP4 (GP4-TL) and number of GS 3 + 4 = 7 cores. As outcome measures, the frequency of adverse pathology (AP) and the risk of biochemical recurrence (BCR) were compared between the GS 6 and 3 + 4 = 7 subgroups. In the %GP4 ≥5% subgroup, only cases with both GP4-TL <0.5 mm and 1 core of GS 3 + 4 = 7 showed similar outcome measures with those of GS 6 cancers. However, all other subgroups showed a higher frequency of AP and/or risk of BCR than GS 6 cancers. Our results suggest that cases with %GP4 ≥5% with a limited amount of GP4 should be considered for inclusion in the active surveillance category.

Diagnostic performance of a nomogram incorporating cribriform morphology for the prediction of adverse pathology in prostate cancer at radical prostatectomy

The aim of the present study was to develop a novel nomogram that incorporated clinical factors, imaging parameters and biopsy pathological factors (including cribriform morphology) to predict adverse pathology in prostate cancer (PCa). A total of 223 patients with PCa, who had undergone preoperative multi-parametric magnetic resonance imaging and had a biopsy of Gleason pattern (GP) 4, absence of GP 5 and pure Grade Group (GG) 3 [Gleason score (GS) 3+4, GS 4+3, GS 4+4], were retrospectively enrolled onto the study. The contribution of GG to the biopsy and Prostate Imaging Reporting and Data System (PI-RADS) score for PCa harboring adverse pathology were analyzed. Univariate and multivariate logistic regression analyses were performed to determine significant pathology predictors of adverse pathology for nomogram development. The nomogram was internally validated using bootstrapping with 1,000 iterations. The diagnostic performance of the nomogram was analyzed by receiver operating characteristics (ROC) analysis and decision curve analysis (DCA). A higher biopsy GG and PI-RADS score were associated with an increased likelihood of adverse pathology. Prostate specific antigen density (PSAD), biopsy GG, cribriform morphology on biopsy and PI-RADS score were significant predictors and were included in the nomogram. The ROC area under the curve of the nomogram was 0.88 (95% confidence interval, 0.84-0.91), with a high specificity (0.91) and moderate sensitivity (0.72). The novel nomogram was shown to have a higher net benefit for the prediction of adverse pathology in PCa, compared with any individual factors determined by DCA. Overall, a novel nomogram incorporating PSAD, PI-RADS score, biopsy GG and cribriform morphology on biopsy was shown to perform well in the prediction of PCa harboring adverse pathology at the time of radical prostatectomy.

Cases Having a Gleason Score 3+4=7 With <5% of Gleason Pattern 4 in Prostate Needle Biopsy Show Similar Failure-free Survival and Adverse Pathology Prevalence to Gleason Score 6 Cases in a Radical Prostatectomy Cohort

Recent discussions have suggested expanding the inclusion criteria for active prostate cancer surveillance to include cases with a Gleason score (GS) of 3+4=7. In this study, we examined this proposed use of a limited percent Gleason pattern 4 (%GP4) to identify candidates of active surveillance among 315 patients who underwent radical prostatectomy for prostate cancer with a GS of 6 or 3+4=7 via needle biopsy. The latter cases were divided into 4 groups using highest or overall %GP4 cut-off values of 5% and 10% as determined from prostate needle biopsies. The frequency of adverse pathology and risk of biochemical recurrence were compared between the GS 6 and both GS 3+4=7 groups. Adverse pathology was defined as a GS 4+3=7 or higher, pT3b staging or positive lymph node metastasis. Notably, the Gleason pattern 4 <5% and GS 6 groups did not differ significantly in terms of the frequency of adverse pathology and risk of biochemical recurrence by the highest method. However, other highest Gleason pattern 4 categories had significantly higher frequencies and risks. Using the overall method, even the Gleason pattern 4 <5% group had a significantly higher frequency of adverse pathology and risk of biochemical recurrence relative to the GS 6 group. In conclusion, our findings suggest that patients with a GS 3+4=7 on biopsy with a highest %GP4 <5% are similar candidates for active surveillance to men with GS 6 cancers.

Risk of Metastasis in Men with Grade Group 2 Prostate Cancer Managed with Active Surveillance at a Tertiary Cancer Center

PURPOSE

We studied the risk of metastatic prostate cancer development in men with Grade Group 2 disease managed with active surveillance at Memorial Sloan Kettering Cancer Center.

MATERIALS AND METHODS

A total of 219 men with Grade Group 2 prostate cancer had disease managed with active surveillance between 2000 and 2017. Biopsy was performed every 2 to 3 years, or upon changes in magnetic resonance imaging, prostate specific antigen level or digital rectal examination. The primary outcome was development of distant metastasis. The Kaplan-Meier method was used to estimate treatment-free survival.

RESULTS

Median age at diagnosis was 67 years (IQR 61-72), median prostate specific antigen was 5 ng/ml (IQR 4-7) and most patients (69%) had nonpalpable disease. During followup 64 men received treatment, including radical prostatectomy in 36 (56%), radiotherapy in 20 (31%), hormone therapy in 3 (5%) and focal therapy in 5 (8%). Of the 36 patients who underwent radical prostatectomy 32 (89%) had Grade Group 2 disease on pathology and 4 (11%) had Grade Group 3 disease. Treatment-free survival was 61% (95% CI 52-70) at 5 years and 49% (95% CI 37-60) at 10 years. Three men experienced biochemical recurrence, no men had distant metastasis and no men died of prostate cancer during the followup. Median followup was 3.1 years (IQR 1.9-4.9).

CONCLUSIONS

Active surveillance appears to be a safe initial management strategy in the short term for carefully selected and closely monitored men with Grade Group 2 prostate cancer treated at a tertiary cancer center. Definitive conclusions await further followup.

Clinical significance and predictors of oncologic outcome after radical prostatectomy for invisible prostate cancer on multiparametric MRI

Background

The objective of our study was to evaluate the clinical significance of invisible prostate cancer (iPCa) on multiparametric magnetic resonance imaging (mpMRI) by analyzing clinical parameters and oncologic outcomes.

Methods

We retrospectively reviewed the records of patients treated with radical prostatectomy (RP) from 2010 to 2015 at our institution. Before RP, all patients were confirmed to have prostate cancer based on prostate biopsy. We excluded patients who underwent neoadjuvant therapy. Additionally, we excluded patients who had incomplete mpMRI based on PI-RADS (Prostate Imaging Reporting and Data System). iPCa was defined as having no grade 3 or higher region of interests using a scoring system established by PI-RADS without limitations on interpretation from mpMRI by radiologists. We selected patients with iPCa using this protocol. We analyzed data using univariate and multivariate cox regression analysis, logistic analysis, Kaplan-Meier curves, and receiver operator characteristic curves to predict biochemical recurrence (BCR).

Results

A total of 213 patients with iPCa were selected according to the patient selection protocol. Among them, pathological findings showed that Gleason score (GS) G6, G7 and ≥ G8 were present in 115 cases (54.0%), 78 cases (36.6%), and 20 cases (9.4%), respectively. Further, extracapsular extension (ECE), positive surgical margins (PSM), and lymphovascular invasion (LVI) were present in 28 (13.1%), 18 (8.5%), and 3 cases (1.4%), respectively. Seminal vesicle invasion (SVI) was observed in one case (0.5%). During a median follow-up time of 51 months, BCR was observed 29 cases. Adverse pathology (AP) was defined as GS ≥8, ECE, SVI and LVI. AP and prostate specific antigen (PSA) were significantly associated with BCR. Moreover, PSA > 6.2 ng/ml was suggested as a cut-off value for predicting BCR.

Conclusions

In our results, cases of iPCa had clinically significant PCa, and AP and poor prognosis were also observed in some. Additionally, we found that PSA is the most clinically reliable predictor of oncologic outcome. We suggest that active treatment and diagnosis should be considered for patients with iPCa with PSA > 6.2 ng/ml.