Prostate Cancer Risk Stratification by Simple Scoring of the Current pT3 Lesions: A Proposal for a New Pathologic T-Staging System

Cancer spread beyond the prostate, including extraprostatic extension (other than seminal vesicle or bladder invasion; EPE)/microscopic bladder neck invasion and seminal vesicle invasion (SVI) currently classified as pT3a and pT3b lesions, respectively, does not uniformly indicate poor oncologic outcomes. Accurate risk stratification of current pT3 disease is therefore required. We herein further determined the prognostic impact of these histopathologic lesions routinely assessed and reported by pathologists, particularly their combinations. We assessed consecutive 2892 patients undergoing radical prostatectomy for current pT2 (n = 1692), pT3a (n = 956), or pT3b (n = 244) disease at our institution between 2009 and 2018. Based on our preliminary findings, point(s) were given (1 point to focal EPE, microscopic bladder neck invasion, or unilateral SVI; 2 points to nonfocal/established EPE or bilateral SVI) and summed up in each case. Our cohort had 0 point (n = 1692, 58.5%; P0), 1 point (n = 243, 8.4%; P1), 2 points (n = 657, 22.7%; P2), 3 points (n = 192, 6.6%; P3), 4 points (n = 76, 2.6%; P4), and 5 points (n = 32, 1.1%; P5). Univariate analysis revealed associations of higher points with significantly worse biochemical progression-free survival, particularly when P4 and P5 were combined. In multivariable analysis (P0 as a reference), P1 (hazard ratio [HR], 1.57; P = .033), P2 (HR, 3.25; P < .001), P3 (HR, 4.01; P < .001), and P4 + P5 (HR, 5.99; P < .001) showed significance for the risk of postoperative progression. Meanwhile, Harrell C-indexes for the current pT staging, newly developed point system, and the Cancer of the Prostate Risk Assessment post-Surgical (CAPRA-S) score were 0.727 (95% CI, 0.706-0.748), 0.751 (95% CI, 0.729-0.773), and 0.774 (95% CI, 0.755-0.794), respectively, for predicting progression. We believe our data provide a logical rationale for a novel pathologic T-staging system based on the summed points, pT1a (0 point), pT1b (1 point), pT2 (2 points), pT3a (3 points), and pT3b (4 or 5 points), which more accurately stratifies the prognosis of prostate cancer.

Risk of Biochemical Recurrence in Patients With Grade Group 1 Prostate Cancer With Extraprostatic Extension Treated With Radical Prostatectomy

PURPOSE

We sought to examine the association of extraprostatic extension (EPE) with biochemical recurrence (BCR) separately in men with Grade Group (GG) 1 and GG2 prostate cancer (PCa) treated with radical prostatectomy.

MATERIALS AND METHODS

We reviewed our institutional database of patients who underwent radical prostatectomy for PCa between 2005 and 2022 and identified patients with GG1 and GG2 disease on final pathology. Fine-Gray competing risk models with an interaction between EPE (yes vs no) and GG (GG1 vs GG2) were used to examine the relationship between disease group and BCR-free survival.

RESULTS

The cohort consisted of 6309 men, of whom 169/2740 (6.2%) with GG1 disease had EPE while 1013/3569 (28.4%) with GG2 disease had EPE. Median follow-up was 4 years. BCR occurred in 400/6309 (6.3%) patients. For men with GG1, there was no statistically significant difference in BCR-free survival for men with vs without EPE (subdistribution HR = 0.88; 95% CI: 0.37-2.09). However, for GG2 patients BCR-free survival was significantly worse for those with vs without EPE (subdistribution HR = 1.97, 95% CI: 1.54-2.52).

CONCLUSIONS

Although there is a subset of GG1 PCas capable of invading through the prostatic capsule, patients with GG1 PCa and EPE at prostatectomy experience similar biochemical recurrence and survival outcomes compared to GG1 patients without EPE. However, among men with GG2, EPE connotes a worse prognosis.

Amide proton transfer imaging has added value for predicting extraprostatic extension in prostate cancer patients

Background

Prostate cancer invades the capsule is a key factor in selecting appropriate treatment methods. Accurate preoperative prediction of extraprostatic extension (EPE) can help achieve precise selection of treatment plans.

Purpose

The aim of this study is to verify the diagnostic efficacy of tumor size, length of capsular contact (LCC), apparent diffusion coefficient (ADC), and Amide proton transfer (APT) value in predicting EPE. Additionally, the study aims to investigate the potential additional value of APT for predicting EPE.

Method

This study include 47 tumor organ confined patients (age, 64.16 ± 9.18) and 50 EPE patients (age, 61.51 ± 8.82). The difference of tumor size, LCC, ADC and APT value between groups were compared. Binary logistic regression was used to screen the EPE predictors. The receiver operator characteristic curve analysis was performed to assess the diagnostic performance of variables for predicting EPE. The diagnostic efficacy of combined models (model I: ADC+LCC+tumor size; model II: APT+LCC+tumor size; and model III: APT +ADC+LCC+tumor size) were also analyzed.

Results

APT, ADC, tumor size and the LCC were independent predictors of EPE. The area under the curve (AUC) of APT, ADC, tumor size and the LCC were 0.752, 0.665, 0.700 and 0.756, respectively. The AUC of model I, model II, and model III were 0.803, 0.845 and 0.869, respectively. The cutoff value of APT, ADC, tumor size and the LCC were 3.65%, 0.97×10-3mm2/s, 17.30mm and 10.78mm, respectively. The sensitivity/specificity of APT, ADC, tumor size and the LCC were 76%/89.4.0%, 80%/59.6%, 54%/78.9%, 72%/66%, respectively. The sensitivity/specificity of model I, Model II and Model III were 74%/72.3%, 82%/72.5% and 84%/80.9%, respectively.

Data conclusion

Amide proton transfer imaging has added value for predicting EPE. The combination model of APT balanced the sensitivity and specificity.

Comprehensive analysis of predictive factors for upstaging in intraprostatic cancer after radical prostatectomy: Different patterns of spread exist in lesions at different locations

BACKGROUND

Accurate assessment of the clinical staging is crucial for determining the need for radical prostatectomy (RP) in prostate cancer (PCa). However, the current methods for PCa staging may yield incorrect results. This study aimed to comprehensively analyze independent predictors of postoperative upstaging of intraprostatic cancer.

METHODS

We conducted a retrospective analysis of data from intraprostatic cancer patients who underwent radical surgery between March 2019 and December 2022. Intraprostatic cancer was defined as a lesion confined to the prostate, excluding cases where multiparameter magnetic resonance imaging (mpMRI) showed the lesion in contact with the prostatic capsule. We assessed independent predictors of extraprostatic extension (EPE) and analyzed their association with positive surgical margin (PSM) status. In addition, based on the distance of the lesion from the capsule on mpMRI, we divided the patients into non-transition zone and transition zone groups for further analysis.

RESULTS

A total of 500 patients were included in our study. Logistic regression analysis revealed that biopsy Gleason grade group (GG) (odds ratio, OR: 1.370, 95% confidence interval, CI: 1.093-1.718) and perineural invasion (PNI) (OR: 2.746, 95% CI: 1.420-5.309) were predictive factors for postoperative EPE. Both biopsy GG and PNI were associated with lateral (GG: OR: 1.270, 95% CI: 1.074-1.501; PNI: OR: 2.733, 95% CI: 1.521-4.911) and basal (GG: OR: 1.491, 95% CI: 1.194-1.862; PNI: OR: 3.730, 95% CI: 1.929-7.214) PSM but not with apex PSM (GG: OR: 1.176, 95% CI: 0.989-1.399; PNI: OR: 1.204, 95% CI: 0.609-2.381) after RP. Finally, PNI was an independent predictor of EPE in the transition zone (OR: 11.235, 95% CI: 2.779-45.428) but not in the non-transition zone (OR: 1.942, 95% CI: 0.920-4.098).

CONCLUSION

PNI and higher GG may indicate upstaging of tumors in patients with intraprostatic carcinoma. These two factors are associated with PSM in locations other than the apex of the prostate. Importantly, cancer in the transition zone of the prostate is more likely to spread externally through nerve invasion than cancer in the non-transition zone.

Predictors of Extraprostatic Extension in Patients with Prostate Cancer

PURPOSE

To identify effective factors predicting extraprostatic extension (EPE) in patients with prostate cancer (PCa).

METHODS

This retrospective cohort study recruited 898 consecutive patients with PCa treated with robot-assisted laparoscopic radical prostatectomy. The patients were divided into EPE and non-EPE groups based on the analysis of whole-mount histopathologic sections. Histopathological analysis (ISUP biopsy grade group) and magnetic resonance imaging (MRI) (PI-RADS v2.1 scores [1-5] and the Mehralivand EPE grade [0-3]) were used to assess the prediction of EPE. We also assessed the clinical usefulness of the prediction model based on decision-curve analysis.

RESULTS

Of 800 included patients, 235 (29.3%) had EPE, and 565 patients (70.7%) did not (non-EPE). Multivariable logistic regression analysis showed that the biopsy ISUP grade, PI-RADS v2.1 score, and Mehralivand EPE grade were independent risk factors for EPE. In the regression assessment of the models, the best discrimination (area under the curve of 0.879) was obtained using the basic model (age, serum PSA, prostate volume at MRI, positive biopsy core, clinical T stage, and D'Amico risk group) and Mehralivand EPE grade 3. Decision-curve analysis showed that combining Mehralivand EPE grade 3 with the basic model resulted in superior net benefits for predicting EPE.

CONCLUSION

Mehralivand EPE grades and PI-RADS v2.1 scores, in addition to basic clinical and demographic information, are potentially useful for predicting EPE in patients with PCa.

Significance of extraprostatic extension by Grade Groups 1-3 prostatic carcinoma on needle biopsy

BACKGROUND

It is rare for extraprostatic extension (EPE) on biopsy to be seen with Grade Groups (GG) 1-3 (Gleason scores 3 + 3 = 6; 3 + 4 = 7; 4 + 3 = 7) prostatic adenocarcinoma, and there is no data whether this finding should be a contraindication for performing radical prostatectomy (RP).

METHODS

Thirty eight cases with GG 1-3 prostatic adenocarcinoma as the highest grade in the case with EPE on biopsy were identified from our consultation files. Highly unfavorable findings at RP were those that if they could have been predicted preoperatively, might have factored into the decision of whether to proceed with surgery. For these purposes, highly unfavorable pathology at RP was defined as either the presence of seminal vesicle invasion or lymph node metastases or GG5 (Gleason score 9-10).

RESULTS

Among 37 patients with clinical follow-up data, 18 (49%) received radiation and/or hormonal therapy (RT/HT), 13 patients (35%) either underwent (n = 11) or are planning (n = 2) RP, and 6 patients (16%) received either ablation therapy or active surveillance. Based on the 11 RP pathology reports, 8 were GG2, one GG3 with tertiary pattern 5, and two GG3. Ten cases were reported to have EPE and six cases had positive margins. Only one had highly unfavorable pathology with pT3bN1 disease. The only difference between the RP and the RT/HT groups in their pretreatment parameters was the mean age of the RP patients was 61 compared with 69 for the RT/HT men (p = 0.02); the lack of many cases with highly unfavorable pathology at RP cannot be attributable to a selection bias of men with lower volume cancer on biopsy or lower serum prostate-specific antigen levels choosing RP over RT/HT.

CONCLUSIONS

Despite EPE on biopsy, most men do not have highly unfavorable pathology at RP, and this treatment should remain an option in this setting.

[Comparison of the efficiency of surgical excision methods for detecting extraprostatic extension and positive resection margin in prostate cancer]

On the samples of 26 prostatectomies, the method of excision of the prostate gland according to Kim was tested. This method increased the number of blocks by 30.2% and increased the detectability of extraprostatic extension by 41.7% and positive surgical margin by 40.0% compared to the method of alternate prostate sections. Also, the method according to Kim reduced the number of blocks of prostate tissue by 34.3% compared to the method of complete prostate excision.

Computational Detection of Extraprostatic Extension of Prostate Cancer on Multiparametric MRI Using Deep Learning

The localization of extraprostatic extension (EPE), i.e., local spread of prostate cancer beyond the prostate capsular boundary, is important for risk stratification and surgical planning. However, the sensitivity of EPE detection by radiologists on MRI is low (57% on average). In this paper, we propose a method for computational detection of EPE on multiparametric MRI using deep learning. Ground truth labels of cancers and EPE were obtained in 123 patients (38 with EPE) by registering pre-surgical MRI with whole-mount digital histopathology images from radical prostatectomy. Our approach has two stages. First, we trained deep learning models using the MRI as input to generate cancer probability maps both inside and outside the prostate. Second, we built an image post-processing pipeline that generates predictions for EPE location based on the cancer probability maps and clinical knowledge. We used five-fold cross-validation to train our approach using data from 74 patients and tested it using data from an independent set of 49 patients. We compared two deep learning models for cancer detection: (i) UNet and (ii) the Correlated Signature Network for Indolent and Aggressive prostate cancer detection (CorrSigNIA). The best end-to-end model for EPE detection, which we call EPENet, was based on the CorrSigNIA cancer detection model. EPENet was successful at detecting cancers with extraprostatic extension, achieving a mean area under the receiver operator characteristic curve of 0.72 at the patient-level. On the test set, EPENet had 80.0% sensitivity and 28.2% specificity at the patient-level compared to 50.0% sensitivity and 76.9% specificity for the radiologists. To account for spatial location of predictions during evaluation, we also computed results at the sextant-level, where the prostate was divided into sextants according to standard systematic 12-core biopsy procedure. At the sextant-level, EPENet achieved mean sensitivity 61.1% and mean specificity 58.3%. Our approach has the potential to provide the location of extraprostatic extension using MRI alone, thus serving as an independent diagnostic aid to radiologists and facilitating treatment planning.

Diagnostic Performance of Extraprostatic Extension Grading System for Detection of Extraprostatic Extension in Prostate Cancer: A Diagnostic Systematic Review and Meta-Analysis

Purpose

To evaluate the diagnostic performance of the extraprostatic extension (EPE) grading system for detection of EPE in patients with prostate cancer (PCa).

Materials and Methods

We performed a literature search of Web of Science, MEDLINE (Ovid and PubMed), Cochrane Library, EMBASE, and Google Scholar to identify eligible articles published before August 31, 2021, with no language restrictions applied. We included studies using the EPE grading system for the prediction of EPE, with histopathological results as the reference standard. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR−), and diagnostic odds ratio (DOR) were calculated with the bivariate model. Quality assessment of included studies was performed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

Results

A total of 4 studies with 1,294 patients were included in the current systematic review. The pooled sensitivity and specificity were 0.82 (95% CI 0.76–0.87) and 0.63 (95% CI 0.51–0.73), with the area under the hierarchical summary receiver operating characteristic (HSROC) curve of 0.82 (95% CI 0.79–0.85). The pooled LR+, LR−, and DOR were 2.20 (95% CI 1.70–2.86), 0.28 (95% CI 0.22–0.36), and 7.77 (95% CI 5.27–11.44), respectively. Quality assessment for included studies was high, and Deeks’s funnel plot indicated that the possibility of publication bias was low (p = 0.64).

Conclusion

The EPE grading system demonstrated high sensitivity and moderate specificity, with a good inter-reader agreement. However, this scoring system needs more studies to be validated in clinical practice.

International Society of Urological Pathology (ISUP)-Grade Grouping in Prostatic Adenocarcinoma and its Prognostic Implications

In this study, we evaluated the association of ISUP/WHO-grade groups with various pathological prognostic parameters and cancer-specific survival in patients with prostatic adenocarcinoma. We found 27 (15.7%) cases of grade group 1, 22 (12.8%) grade group 2, 30 (17.4%) grade group 3, 40 (23.3%) grade group 4 and 53 (30.8%) grade group 5 prostatic adenocarcinoma. We found that high-grade tumors (grade 3-5) had a higher frequency of perineural invasion and higher tumor volumes (>50%). Moreover, a significant association of tumor grade was noted with cancer-specific survival of patients, signifying prognostic significance of grade grouping in prostatic adenocarcinoma.

The relationship between amount of extra-prostatic extension and length of capsular contact: performances from MR images and radical prostatectomy specimens

Backround/aim

In prostate cancer, extraprostatic extension (EPE) is an unfavorable prognostic factor, and the grade of EPE is correlated with the prognosis. This study aims to evaluate the utility of length of capsular contact (LCC ) in predicting the grade of EPE by correlating the measurements from MRI images and the measurements performed from radical prostatectomy specimens.

Materials and methods

MR images and specimens of 110 tumors are analyzed retrospectively. The specimens are used as reference to validate the presence of EPE and to measure the ground truth LCC. MR images are evaluated by two radiologists to identify the presence of EPE and to predict the LCC indirectly. Reliability, accuracy, sensitivity, and specificity of the evaluations are analyzed in comparison with the findings obtained from the specimens.

Results

In detection of EPE existence, the radiologists achieve almost the same performance (all AUCs = 0.73) with optimal cut-off values lead to moderate sensitivity and specificity pairs (For cut-off = 15.8 mm; Se = 0.69, Sp = 0.68 and for cut-off of 14.5 mm: Se = 0.77, Sp = 0.62). In distinguishing high-grade EPE from low-grade EPE, the radiologists accomplish very similar performances (AUCs = 0.73 and 0.72) Optimal thresholds of 20.0 mm and 18.5 mm for the readers retrospectively reveal medium sensitivity and specificity pairs (Se = 0.64, Sp = 0.67; Se = 0.64, Sp = 0.67).

Conclusion

Consistent LCC estimates can be obtained from MR images providing a beneficial metric for detecting the existence of EPE and for discriminating the grades of EPE.

Clinical and oncologic findings of extraprostatic extension on needle biopsy in de novo metastatic prostate cancer

This study aimed to explore the clinical and oncologic findings in patients with de novo metastatic prostate cancer (mPCa) and extraprostatic extension (EPE) on biopsy. We retrospectively evaluated data on 630 patients with de novo mPCa between January 2009 and December 2017 in the West China Hospital (Chengdu, China), including evaluating the relationships between EPE and other variables and the association of EPE with survival outcomes by the Chi-square test, Kaplan-Meier curves, and the Cox proportional-hazards model. EPE was found in 70/630 patients, making a prevalence of 11.1%. The presence of EPE on biopsy was associated with higher Gleason scores and higher incidence of neuroendocrine differentiation (NED), intraductal carcinoma of the prostate (IDC-P), and perineural invasion (PNI). Compared with those without EPE, patients with EPE had shorter castration-resistant prostate cancer-free survival (CFS; median: 14.1 vs 17.1 months, P = 0.015) and overall survival (OS; median: 43.7 vs 68.3 months, P = 0.032). According to multivariate analysis, EPE was not an independent predictor for survival. Subgroup analyses demonstrated that patients with favorable characteristics, including negative NED or IDC-P status, Eastern Cooperative Oncology Group (ECOG) score <2, and prostate-specific antigen (PSA) <50 ng ml^-1, had worse prognoses if EPE was detected. In patients with PSA <50 ng ml^-1, EPE was a negative independent predictor for OS (hazard ratio [HR]: 4.239, 95% confidence interval [CI]: 1.218-14.756, P = 0.023). EPE was strongly associated with other aggressive clinicopathological features and poorer CFS and OS. These data suggest that EPE may be an indicator of poor prognosis, particularly in patients, otherwise considered likely to have favorable survival outcomes.

Combining the Tumor Contact Length and Apparent Diffusion Coefficient Better Predicts Extraprostatic Extension of Prostate Cancer with Capsular Abutment: A 3 Tesla MR Imaging Study

Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).

Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm²) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.

Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10^–3 mm²/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).

Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA.

External Validation of the Extraprostatic Extension Grade on MRI and Its Incremental Value to Clinical Models for Assessing Extraprostatic Cancer

Objectives

To externally validate the extraprostatic extension (EPE) grade criteria on MRI and analyze the incremental value of EPE grade to clinical models of prostate cancer.

Methods

A consecutive 130 patients who underwent preoperative prostate MRI followed by radical prostatectomy between January 2015 to January 2020 in our institution were retrospectively enrolled. The EPE grade, Cancer of the Prostate Risk Assessment (CAPRA), and Memorial Sloan Kettering Cancer Center nomogram (MSKCCn) score for each patient were assigned. Significant clinicopathological factors in univariate and multivariate analyses were combined with EPE grade to build the Clinical + EPE grade model, and the CAPRA and MSKCCn score were also combined with EPE grade to build the CAPRA + EPE grade and MSKCCn + EPE grade model, respectively. The area under the curve (AUC), sensitivity and specificity of these models were calculated to evaluate their diagnostic performance. Calibration and decision curve analyses were used to analyze their calibration performance and clinical utility.

Results

The AUC for predicting EPE was 0.767–0.778 for EPE grade, 0.704 for CAPRA, and 0.723 for MSKCCn. After combination with EPE grade, the AUCs of these clinical models increased significantly than using clinical models along (P < 0.05), but was comparable with using EPE grade alone (P > 0.05). The calibration curves of EPE grade, clinical models and combined models showed that these models are well-calibrated for EPE. In the decision curve analysis, EPE grade showed slightly higher net benefit than MSKCCn and CAPRA.

Conclusion

The EPE grade showed good performance for evaluating EPE in our cohort and possessed well clinical utility. Further combinations with the EPE grade could improve the diagnostic performance of clinical models.

Multiparametric MRI in the management of prostate cancer: an update-a narrative review

The growing interest in multiparametric MRI is leading to important changes in the diagnostic process of prostate cancer. MRI-targeted biopsy is likely to become a standard for the diagnosis of prostate cancer in the next years. Despite it is well known that MRI has no role as a staging technique, it is clear that multiparametric MRI may be of help in active surveillance protocols. Noteworthy, MRI in active surveillance is not recommended, but a proper understanding of its potential may be of help in achieving the goals of a delayed treatment strategy. Moreover, the development of minimally invasive techniques, like laparoscopic and robotic surgery, has led to greater expectations as regard to the functional outcomes of radical prostatectomy. Multiparametric MRI may play a role in planning surgical strategies, with the aim to provide the highest oncologic outcome with a minimal impact on the quality of life. We maintain that a proper anatomic knowledge of prostate lesions may allow the surgeon to achieve a better result in planning as well as in performing surgery and help the surgeon and the patient engage in a shared decision in planning a more effective strategy for prostate cancer control and treatment. This review highlights the advantages and the limitations of multiparametric MRI in prostate cancer diagnosis, in active surveillance and in planning surgery.

Radiomics Based on Multiparametric Magnetic Resonance Imaging to Predict Extraprostatic Extension of Prostate Cancer

Background: To develop a radiomics model based on multiparametric MRI (mpMRI) for preoperative prediction of extraprostatic extension (EPE) in patients with prostate cancer (PCa). Methods: Ninety-five pathology-confirmed PCa patients with 115 lesions (49 positive and 66 negative) were retrospectively enrolled. A 3.0T MR scanner was used to perform T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced imaging (DCE). Radiomics features extracted from T2WI, DWI, apparent diffusion coefficient (ADC), and DCE were used to build a radiomics model. Patients' clinical and pathological variables were also obtained to build a clinical model. The radiomics model and clinical model were further integrated to build a combined nomogram. All lesions were randomly divided into the training group (82 lesions) and the validation group (33 lesions). A least absolute shrinkage and selection operator (LASSO) regression algorithm was applied to build the radiomics model. The diagnostic performance of different models was assessed by calculating the area under the curve (AUC) and compared using the Delong test. The calibration curve and decision curve analyses were used to assess the calibration and clinical usefulness of the radiomics model. Results: The AUC values for the radiomics model in the training and validation group were 0.919 and 0.865, respectively, with a good calibration performance. The decision curve analysis confirmed the clinical utility of the radiomics model. The accuracy, sensitivity, and specificity were 81.8, 71.4, and 89.5% in the validation group. In the validation group, the radiomics model outperformed the clinical model (AUC = 0.658, P = 0.020), and was comparable with the combined nomogram (AUC = 0.857, P = 0.644). Conclusion: The radiomics model based on mpMRI could different EPE and non-EPE lesions with satisfactory diagnostic performance, and this model might assist in predicting EPE before prostatectomy.

Can Extraprostatic Extension Be Predicted by Tumor-Capsule Contact Length in Prostate Cancer? Relationship With International Society of Urological Pathology Grade Groups

OBJECTIVE. The objective of our study was to evaluate the relationship between the tumor-capsule contact length, defined as tumor contact length (TCL), and extraprostatic extension (EPE) using the MRI-based TCL measurements and the real TCL measurements from pathology and to determine whether the International Society of Urological Pathology (ISUP) grade group of the tumors influenced this relationship. MATERIALS AND METHODS. In this retrospective study, we reviewed prostate multiparametric MRI (mpMRI) studies performed between 2012 and 2018 of 1576 patients and found that 134 patients also underwent radical prostatectomy (RP) after mpMRI. Finally, 86 patients with index lesions in contact with the prostate capsule in RP specimens were enrolled in the study. ROC analysis was used to evaluate the cutoff values of TCLs measured at pathology and TCLs measured on MRI in terms of EPE according to ISUP grade groups. RESULTS. There was no statistically significant cutoff value for pathology-based TCL measurements in individual ISUP grade groups and subgroups. Although not statistically significant, pathology-based TCL cutoff values decreased (from 21.0 to 11.0 mm) as ISUP grade group increased in terms of EPE positivity. When the relationship between MRI-based TCL measurements and EPE was considered, statistically significant cutoff values (range, 14.5-16.6 mm) could be determined in many groups and subgroups with low ISUP grades (sensitivity, 66.7-100%; specificity, 52.8-93.0%; p = 0.006-0.042). However, no statistically significant cutoff value was found for high ISUP grades. CONCLUSION. ISUP grade groups may have an effect on the TCL-EPE relationship. When the MRI-based TCL and EPE relationship is evaluated independent of ISUP grade group, a cutoff value around 15-16 mm may be usable to predict EPE.

Comparison of preoperative locoregional Ga-68 PSMA-11 PET-CT and mp-MRI results with postoperative histopathology of prostate cancer

BACKGROUND

Conventional imaging modalities are inadequate to evaluate locoregional extension of prostate cancer (PCa). The aim of the current retrospective study was to investigate the diagnostic efficacy of Gallium-68 prostate-specific membrane antigen-11 (Ga-68 PSMA-11) positron emission tomography/computed tomography (PET/CT) and multiparametric magnetic resonance imaging (mp-MRI) for staging preoperative PCa patients with correlating histopathology.

MATERIALS AND METHODS

Twenty-four patients with histologically proven PCa underwent both Ga-68 PSMA-11 PET/CT and mp-MRI before robot-assisted laparoscopic radical prostatectomy. For each tumor area, correlations with histopathological results were defined for tumor localization, extraprostatic extension (EPE) of the tumor, invasion of seminal vesicle (SVI) and bladder neck invasion (BNI). In patients with regional lymph node (LN) dissection, histopathological results were also correlated with imaging modalities.

RESULTS

Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for detection of EPE and SVI were higher for mp-MRI than Ga-68 PSMA-11 PET/CT. On the other hand Ga-68 PSMA-11 PET/CT had significant successful results for detection of LN metastases when compared with mp-MRI. But for BNI detection both modalities had same insufficient results. Ga-68 PSMA-11 PET/CT had strong results for appropriate tumor localization in the gland.

CONCLUSION

Ga-68 PSMA PET/CT has superior results for assessing local LN metastases and for intraprostatic tumor localization. Whereas, mp-MRI must be the preferred modality for determining SVI and EPE. But both imaging modalities failed for determining BNI accurately. Both modalities should be used in conjunction with each other for better treatment planning.

Apparent diffusion coefficient in extraprostatic extension of prostate cancer: a systematic review and diagnostic meta-analysis

Objective: To evaluate the diagnostic performance of apparent diffusion coefficient (ADC) for local staging of prostate cancer.

Methods: Databases of Web of Science, MEDLINE (Ovid and PubMed), Cochrane Library, EMBASE, and Google Scholar were searched up to May 31, 2018, with language restricted to English. All studies concerning multiparametric magnet resonance imaging (mpMRI) with ADC for detection of extracapsular extension (ECE, T3a) and/or extraprostatic extension (EPE, overall stage of T3) were identified by two reviewers independently, and quality of included studies was evaluated using Quality Assessment of Diagnostic Accuracy Studies-2 tool. True positive, false positive, false negative and true negative of each study were extracted to reconstruct the 2×2 tables for evaluating diagnostic accuracy. Summary estimates of sensitivity, specificity, and corresponding 95% CIs were calculated with bivariate model and hierarchical summary receiver operating characteristic model, then presented in forest plots. Multiple subgroup analyses and meta-regression were performed, and publication bias was evaluated with Deeks funnel.

Results: A total of 18 studies were included, with 6 involved ECE and 12 for EPE. Pooled sensitivity was 80.5% (95% CI 76.5–83.9%) with specificity of 69.1% (95% CI 62.3–75.2%). Multiple subgroup analyses showed that if ADC and length of capsular contact are regarded as independent predictors, pooled sensitivity was 85% (95% CI 77–90%) and 81.1% (95% CI 76.0–85.3%), with specificity of 70.8% (95% CI 56.3–82.0%) and 66.6% (95% CI 57.6–74.5%), respectively. Meta-regression demonstrated that there was no substantially significant difference in types of coil, magnet field strength (1.5T versus 3.0T), and analysis method (per-lesion versus per-patient).

Conclusion: By introducing ADC to MRI, we could obtain favorable sensitivity for diagnostic performance of EPE, but with a little decreased specificity.

3.0-T multiparametric magnetic resonance imaging modifies the template of endoscopic, conventional radical prostatectomy in all cancer risk categories

INTRODUCTION

We aimed to evaluate the diagnostic performance of 3.0-T multiparametric magnetic resonance imaging (mpMRI) in preoperative staging of prostate cancer (PCa) and its influence on the extent of resection during endoscopic radical prostatectomy (ERP) among cancer risk groups.

MATERIAL AND METHODS

The data of 154 patients with PCa in whom mpMRI was performed prior to ERP between 2011 and 2015 were included. The initial decision whether to perform neurovascular bundle (NVB) sparing surgery was based on EAU guidelines. mpMRI images were reevaluated prior to prostatectomy to modify the surgical template. Imaging was compared with pathological reports to investigate the diagnostic performance of mpMRI.

RESULTS

The surgical template was modified in 69 (44.8%) patients after reevaluation of mpMRI. More preserving NVB sparing was attempted in 17 (11.0%) men, in whom NVB would have been resected if mpMRI had not been available. More aggressive NVB resection was performed in 52 (33.8%) men, in whom innervation would have been spared if basing solely based on guidelines. Among all PCa risk groups mpMRI had an impact on the surgical template with more aggressive surgery in 63.0% and 33.3% of men in the low- and intermediate-risk group, respectively, and more preserving in 21.4% of the high-risk patients. The change in extent of resection was not correlated with a higher risk of positive surgical margins (p = 0.196).

CONCLUSIONS

Preoperative mpMRI exerts a significant impact on decision making concerning the extent of resection during ERP irrespective of the PCa risk group.

Prognostic significance and biopsy characteristics of prostate cancer with seminal vesicle invasion on radical prostatectomy: a nationwide population-based study

The objective of this study was to evaluate the prognostic significance of seminal vesicle invasion (SVI, pT3b) compared with extraprostatic extension (EPE) alone (pT3a) after radical prostatectomy, and to correlate pre-operative biopsy pathology with SVI and EPE. The National Prostate Cancer Register includes all prostate cancers diagnosed in Sweden. We analysed 4063 cases with stage category pT3a and 1371 cases with pT3b at radical prostatectomy between 2000 and 2012. Associations between pT3a and pT3b and progression were evaluated and adjusted for year, age, biopsy grade and s-PSA. Needle biopsy findings in these stages were compared. Patients with pT3b (n=1371) had a higher risk of death from prostate cancer (HR 2.3, 95% CI 1.5-3.3, p<0.001) and death from any cause (HR 1.5, 95% CI 1.2-1.8, p<0.001) than those with pT3a (n=4063). They were also more likely to be treated with post-operative radiotherapy (HR 1.5, 95% CI 1.4-1.7, p<0.001) or androgen deprivation therapy (HR 3.0, 95% CI 2.5-3.7, p<0.001), indicating clinical progression. Yet, disease-specific survival of patients with stage pT3b was 94% after 6 years. Median cancer extent in pre-operative biopsies of pT3a and pT3b was 14 and 24 mm (p<0.001), number of positive cores was four and five, (p<0.001) and biopsy Gleason score was 8-10 in 11.6% and 27.3%, respectively (p<0.001). SVI of prostate cancer is associated with worse outcome after radical prostatectomy than EPE alone. However, few patients with SVI die within 6 years from surgery, suggesting that radical prostatectomy may be curative in locally advanced cancers.

Evaluation of MRI for diagnosis of extraprostatic extension in prostate cancer

PURPOSE

To assess the ability of magnetic resonance imaging (MRI) to diagnose extraprostatic extension (EPE) in prostate cancer.

MATERIALS AND METHODS

With Institutional Review Board (IRB) approval, 149 men with 170 ≥0.5 mL tumors underwent preoperative 3T MRI followed by radical prostatectomy (RP) between 2012-2015. Two blinded radiologists (R1/R2) assessed tumors using Prostate Imaging Reporting and Data System (PI-RADS) v2, subjectively evaluated for the presence of EPE, measured tumor size, and length of capsular contact (LCC). A third blinded radiologist, using MRI-RP-maps, measured whole-lesion: apparent diffusion coefficient (ADC) mean/centile and histogram features. Comparisons were performed using chi-square, logistic regression, and receiver operator characteristic (ROC) analysis.

RESULTS

The subjective EPE assessment showed high specificity (SPEC = 75.4/91.3% [R1/R2]), low sensitivity (SENS = 43.3/43.6% [R1/R2]), and area-under (AU) ROC curve = 0.67 (confidence interval [CI] 0.61-0.73) R1 and 0.61 (CI 0.53-0.70) R2; (k = 0.33). PI-RADS v2 scores were strongly associated with EPE (P < 0.001 / P = 0.008; R1/R2) with AU-ROC curve = 0.72 (0.64-0.79) R1 and 0.61 (0.53-0.70) R2; (k = 0.44). Tumors with EPE were larger (18.8 ± 7.8 [median 17, range 6-51] vs. 18.8 ± 4.9 [12, 6-28] mm) and had greater LCC (21.1 ± 14.9 [16, 1-85] vs. 13.6 ± 6.1 [11.5, 4-30] mm); P < 0.001 and 0.002, respectively. AU-ROC for size was 0.73 (0.64-0.80) and LCC was 0.69 (0.60-0.76), respectively. Optimal SENS/SPEC for diagnosis of EPE were: size ≥15 mm = 67.7/66.7% and LCC ≥11 mm = 84.9/44.8%. 10^th -centile ADC and ADC entropy were both associated with EPE (P = 0.02 and < 0.001), with AU-ROC = 0.56 (0.47-0.65) and 0.76 (0.69-0.83), respectively. Optimal SENS/SPEC for diagnosis of EPE with entropy ≥6.99 was 63.3/75.0%. 25^th -centile ADC trended towards being significantly lower with EPE (P = 0.06) with no difference in other ADC metrics (P = 0.25-0.88). Size, LCC, and ADC entropy improved sensitivity but reduced specificity compared with subjective analysis with no difference in overall accuracy (P = 0.38).

CONCLUSION

Measurements of tumor size, capsular contact, and ADC entropy improve sensitivity but reduce specificity for diagnosis of EPE compared to subjective assessment.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:176-185.

MRI assessment of pathological stage and surgical margins in anterior prostate cancer (APC) using subjective and quantitative analysis

PURPOSE

To evaluate magnetic resonance imaging (MRI) for assessment of extraprostatic extension (EPE) and positive surgical margins (PSM) in anterior prostate cancer (APC).

MATERIALS AND METHODS

With Institutional Review Board approval, 25 APC (>2/3 of tumor anterior to urethra) were assessed using 3T MRI by two blinded radiologists for: size and maximal leading edge of tumor (relative to anterior fibromuscular stroma [AFMS]) on b ≥1000 sec/mm² echo-planar-MRI fused onto T₂ -weighted-MRI, invasion of AFMS and EPE. Comparisons were performed between APCs by EPE/PSM using chi-square, multivariable analysis, and receiver operator characteristic (ROC) analysis.

RESULTS

The prevalence of EPE and PSM were 52% (13/25) and 36% (9/25). Tumor sizes were larger with EPE (22.5 ± 8.4 vs. 14.7 ± 6.3, P = 0.02) and PSM (23.0 ± 9.3 vs. 16.4 ± 7.0, P = 0.06). Area under ROC curve (AUC-ROC) for the diagnosis of EPE by tumor size was 0.77 (95% confidence interval [CI] 0.58-0.95); ≥16 mm size = sensitivity/specificity 69.2/66.7%. Maximal leading edge of tumor was greater with EPE (2.4 ± 2.2 vs. -0.2 ± 3.0) and PSM (2.8 ± 2.3 vs. -0.3 ± 2.5), (P = 0.023, 0.031). AUC-ROC for diagnosis of EPE/PSM by leading edge was 0.78 (CI 0.57-0.97) and 0.75 (CI 0.56-0.94). A ≥1 mm leading edge yielded sensitivity/specificity of 76.9/75.0% and 77.8/62.5% for diagnosis of EPE/PSM. 60-72% (15-18/25) tumors invaded AFMS (k = 0.74), which was not associated with EPE/PSM (P = 0.12-0.14). Radiologists' assessment of EPE had sensitivity/specificity of 61.5-69.2/50.0-75.0% (k = 0.53).

CONCLUSION

Tumor size and leading edge of tumor relative to AFMS may enable diagnosis of EPE and positive surgical margins in APC.

LEVEL OF EVIDENCE

2 J. MAGN. RESON. IMAGING 2017;45:1296-1303.

Extraprostatic extension (EPE) of prostatic carcinoma: is its proximity to the surgical margin or Gleason score important?

OBJECTIVE

To examine the association between histopathological factors of extraprostatic prostate cancer and outcome.

PATIENTS AND METHODS

Patients with extraprostatic extension (EPE) without positive margins, seminal vesicle or lymph node involvement were analysed from a consecutive radical prostatectomy cohort of 1136 (2002-2006) for: (i) distance of EPE from the margin; (ii) Gleason score of the EPE; and (iii) extent of EPE. Log-rank, Kaplan-Meier, and Cox regression analyses were performed.

RESULTS

The study included 194 pT3a, pN0, R0 patients with a median follow-up of 5.4 years, with 37 (19%) patients experiencing biochemical relapse (BCR). On univariable analysis, patients with a Gleason score of ≥8 in the extraprostatic portion showed increased incidence of BCR compared with those with Gleason scores of ≤7 (P = 0.03). The proximity of the EPE to the margin (0.01-7.5 mm) did not correlate with BCR. On multivariable analysis, the extent of EPE, the Gleason score of the dominant nodule or of the EPE portion did not correlate with BCR.

CONCLUSION

Data from this study using current International Society of Urological Pathology Gleason scoring and EPE criteria indicate that close proximity of EPE to the margin is not associated with recurrence. Gleason score ≥8 within EPE is associated with an increased BCR risk on univariable analysis, but larger studies are required to confirm whether extensive Gleason pattern 4 in an EPE indicates increased risk in an otherwise overall Gleason score 7 cancer.

Prognostic significance of histopathological features of extraprostatic extension of prostate cancer

AIMS

The 2009 International Society of Urological Pathology consensus conference recommended reporting the extent of extraprostatic extension (EPE) for the prediction of outcome in prostate cancer. Our aim was to stratify EPE into prognostic groups.

METHODS AND RESULTS

We reviewed 1051 radical prostatectomy (RP) specimens from 1998 to 2005. EPE was classified according to the extent, laterality and presence of perineural invasion (PNI) at the site of EPE. Cox regression was used to explore associations with biochemical recurrence. EPE was observed in 470 cases (44.7%), and predicted a higher progression rate than for organ-confined cancer [hazard ratio (HR) 1.4, 95% confidence interval (CI) 1.1-1.8, P = 0.007]. Focal versus established EPE according to Epstein (HR 2.0, 95% CI 1.1-3.5, P = 0.027) and Wheeler (HR 2.2, 95% CI 1.2-3.9, P = 0.010), and the radial distance of EPE dichotomized by the median (1.1 mm) (HR 1.5, 95% CI 1.1-2.2, P = 0.015), were all predictive of recurrence; but PNI at the site of EPE, circumferential length of EPE, number of sections and foci with EPE, and bilateral versus unilateral EPE were not.

CONCLUSIONS

The radial extent of EPE predicts recurrence after RP, but circumferential extent, PNI at the site of EPE, number of sections or foci of EPE, and laterality do not. If validated, the proposed radial extent method may allow for more reproducible quantitation of EPE.

Extraprostatic extension into periprostatic fat is a more important determinant of prostate cancer recurrence than an invasive phenotype

PURPOSE

Although micrometastasis development correlates closely with the depth of invasion of many tumor types, it is unclear whether invasion into but not through the prostatic pseudocapsule has a negative impact on prognosis, similar to extraprostatic extension. We defined the impact of pseudocapsular invasion on the risk of post-prostatectomy biochemical recurrence.

MATERIALS AND METHODS

Patients with pT2-3a prostate cancer were identified from a prospectively recorded database. Those with pT2 disease were categorized according to pseudocapsular invasion presence or absence. The impact of pseudocapsular invasion on biochemical recurrence was determined by univariable and multivariable Cox regression analysis.

RESULTS

In a cohort of 1,338 patients we identified 595 with organ confined cancer positive for pseudocapsular invasion. Compared to tumors without evidence of invasion, pseudocapsular invasion was positively associated with higher Gleason grade and tumor volume (1.2 vs 1.9 cc, each p<0.001). On univariable analysis there was no difference in biochemical recurrence-free survival between patients with vs without pseudocapsular invasion, although those with extraprostatic extension had significantly lower biochemical recurrence-free survival (p<0.001). This was confirmed on multivariable analysis, which revealed that extraprostatic extension was a significant independent predictor of biochemical recurrence (HR 1.53, p=0.018). The presence of pseudocapsular invasion had no effect (HR 0.81, p=0.33).

CONCLUSIONS

Pseudocapsular invasion is not a pathological feature associated with an adverse outcome after prostatectomy. Thus, the depth of tumor invasion is not a continuum of risk and access to periprostatic adipose tissue is a more important determinant of disease behavior than an invasive phenotype.

Adjuvant and salvage radiotherapy after prostatectomy: AUA/ASTRO Guideline

PURPOSE

The purpose of this guideline is to provide a clinical framework for the use of radiotherapy after radical prostatectomy as adjuvant or salvage therapy.

MATERIALS AND METHODS

A systematic literature review using the PubMed®, Embase, and Cochrane databases was conducted to identify peer-reviewed publications relevant to the use of radiotherapy after prostatectomy. The review yielded 294 articles; these publications were used to create the evidence-based guideline statements. Additional guidance is provided as Clinical Principles when insufficient evidence existed.

RESULTS

Guideline statements are provided for patient counseling, the use of radiotherapy in the adjuvant and salvage contexts, defining biochemical recurrence, and conducting a re-staging evaluation.

CONCLUSIONS

Physicians should offer adjuvant radiotherapy to patients with adverse pathologic findings at prostatectomy (i.e., seminal vesicle invasion, positive surgical margins, extraprostatic extension) and should offer salvage radiotherapy to patients with prostatic specific antigen or local recurrence after prostatectomy in whom there is no evidence of distant metastatic disease. The offer of radiotherapy should be made in the context of a thoughtful discussion of possible short- and long-term side effects of radiotherapy as well as the potential benefits of preventing recurrence. The decision to administer radiotherapy should be made by the patient and the multi-disciplinary treatment team with full consideration of the patient's history, values, preferences, quality of life, and functional status. Please visit the ASTRO and AUA websites (http://www.redjournal.org/webfiles/images/journals/rob/RAP%20Guideline.pdf and http://www.auanet.org/education/guidelines/radiation-after-prostatectomy.cfm) to view this guideline in its entirety, including the full literature review.

Predictive factors of oncologic outcomes in patients who do not achieve undetectable prostate specific antigen after radical prostatectomy. J Urol. 2013;190:1750-1756. [PMID: 23643600 DOI: 10.1016/j.juro.2013.04.073]

PURPOSE

We identified factors predicting oncologic outcomes in cases of persistently detectable prostate specific antigen.

MATERIALS AND METHODS

We reviewed the charts of patients treated with radical prostatectomy between 1998 and 2011 at a total of 14 centers. Study inclusion criteria were radical prostatectomy for presumed localized prostate cancer, absent positive nodes and detectable prostate specific antigen, defined as prostate specific antigen 0.1 ng/ml or greater 6 weeks postoperatively. Of the 9,735 radical prostatectomy cases reviewed 496 (5.1%) were eligible for analysis. Predictive factors for oncologic outcomes were assessed in time dependent analyses using the Kaplan-Meier method and Cox regression models.

RESULTS

At 6 weeks prostate specific antigen was 0.1 to 6.8 ng/ml. Biochemical progression was noted in 74.4% of patients and clinical metastasis was noted in 5%. The 2 most powerful predictors of general salvage treatment (vs radiotherapy) were postoperative prostate specific antigen greater than 1 ng/ml (OR 3.46, p=0.032) and prostate specific antigen velocity greater than 0.2 ng/ml per year (HR 6.01, p=0.001). Positive prostate specific antigen velocity was the single factor that independently correlated with the risk of failed salvage therapy (HR 2.6, p=0.001). The 5-year disease-free survival rate was 81.0% in patients with stable or negative prostate specific antigen velocity compared with 58.4% in those with positive prostate specific antigen velocity (p<0.001).

CONCLUSIONS

Patients with detectable prostate specific antigen after radical prostatectomy have a poor biochemical outcome. We identified postoperative prostate specific antigen and prostate specific antigen velocity as independent predictors of progression and failed salvage treatment. In addition to pathological prognostic factors, these factors should be considered early to better stratify patients for adjuvant therapy.