Do robotic prostatectomy positive surgical margins occur in the same location as extraprostatic extension?

Prediction of extracapsular extension of prostate cancer by MRI radiomic signature: a systematic review

The objective of this review is to survey radiomics signatures for detecting pathological extracapsular extension (pECE) on magnetic resonance imaging (MRI) in patients with prostate cancer (PCa) who underwent prostatectomy. Scientific Literature databases were used to search studies published from January 2007 to October 2023. All studies related to PCa MRI staging and using radiomics signatures to detect pECE after prostatectomy were included. Systematic review was performed according to Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA). The risk of bias and certainty of the evidence was assessed using QUADAS-2 and the radiomics quality score. From 1247 article titles screened, 16 reports were assessed for eligibility, and 11 studies were included in this systematic review. All used a retrospective study design and most of them used 3 T MRI. Only two studies were performed in more than one institution. The highest AUC of a model using only radiomics features was 0.85, for the test validation. The AUC for best model performance (radiomics associated with clinical/semantic features) varied from 0.72-0.92 and 0.69-0.89 for the training and validation group, respectively. Combined models performed better than radiomics signatures alone for detecting ECE. Most of the studies showed a low to medium risk of bias. After thorough analysis, we found no strong evidence supporting the clinical use of radiomics signatures for identifying extracapsular extension (ECE) in pre-surgery PCa patients. Future studies should adopt prospective multicentre approaches using large public datasets and combined models for detecting ECE.

CRITICAL RELEVANT STATEMENT

The use of radiomics algorithms, with clinical and AI integration, in predicting extracapsular extension, could lead to the development of more accurate predictive models, which could help improve surgical planning and lead to better outcomes for prostate cancer patients.

PROTOCOL OF SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021272088. Published: https://doi.org/10.1136/bmjopen-2021-052342 .

KEY POINTS

Radiomics can extract diagnostic features from MRI to enhance prostate cancer diagnosis performance. The combined models performed better than radiomics signatures alone for detecting extracapsular extension. Radiomics are not yet reliable for extracapsular detection in PCa patients.

Detection of extraprostatic extension by transperineal multiparametric magnetic resonance imaging-ultrasound fusion targeted combined with systemic template prostate biopsy

BACKGROUND

Extraprostatic extension (EPE) of prostate cancer (PCa) on transrectal (TR) needle core biopsy (Bx) is a rare histopathological finding that can help in clinical decision-making. The detection efficiency of the transperineal (TP) approach is yet to be explored.

METHODS

We retrospectively reviewed 2848 PCa cases using concomitant systemic template biopsy (SBx) and multiparametric magnetic resonance imaging (MRI)-ultrasound fusion-targeted biopsy (TBx) using the TR (n = 1917) or TP (n = 931) approach at our institution between January 2015 and July 2022. We assessed and compared clinical, MRI, and biopsy characteristics using different approaches (TP and TR) and methods (SBx and TBx).

RESULTS

In total, 40 EPE cases were identified (40/2848, 1.4%). TP showed a significantly higher EPE detection rate compared to TR in SBx (TR:0.7% vs. TP:1.6%; p = 0.028) and TBx (TR:0.5% vs. TP:1.2%; p = 0.033), as well as the combined methods (2.1% vs. 1.1%, p = 0.019). A significantly higher incidence of EPEs was found at non-base sites in TP than in TR (76.7% vs. 50%, p = 0.038). SBx showed a higher EPE detection rate than TBx; however, the difference was not statistically significant. TP showed higher prostate-specific antigen density (0.35 vs. 0.17, p = 0.005), higher frequency of GG4-5 in the cores with EPE (65.0% vs. 50.0%, p = 0.020), and more PCa-positive SBx cores (10 vs. 8, p = 0.023) compared to the TR.

CONCLUSIONS

TP may improve EPE detection compared with TR and should be applied to patients with adverse pre-biopsy features.

Machine learning in predicting extracapsular extension (ECE) of prostate cancer with MRI: a protocol for a systematic literature review

INTRODUCTION

In patients with prostate cancer (PCa), the detection of extracapsular extension (ECE) and seminal vesicle invasion is not only important for selecting the appropriate therapy but also for preoperative planning and patient prognosis. It is of paramount importance to stage PCa correctly before surgery, in order to achieve better surgical and outcome results. Over the last years, MRI has been incorporated in the classical prostate staging nomograms with clinical improvement accuracy in detecting ECE, but with variability between studies and radiologist's experience.

METHODS AND ANALYSIS

The research question, based on patient, index test, comparator, outcome and study design criteria, was the following: what is the diagnostic performance of artificial intelligence algorithms for predicting ECE in PCa patients, when compared with that of histopathological results after radical prostatectomy. To answer this question, we will use databases (EMBASE, PUBMED, Web of Science and CENTRAL) to search for the different studies published in the literature and we use the QUADA tool to evaluate the quality of the research selection.

ETHICS AND DISSEMINATION

This systematic review does not require ethical approval. The results will be disseminated through publication in a peer-review journal, as a chapter of a doctoral thesis and through presentations at national and international conferences.

PROSPERO REGISTRATION NUMBER

CRD42020215671.

Prostate Magnetic Resonance Imaging Analyses, Clinical Parameters, and Preoperative Nomograms in the Prediction of Extraprostatic Extension

Introduction: Proper planning of laparoscopic radical prostatectomy (RP) in patients with prostate cancer (PCa) is crucial to achieving good oncological results with the possibility of preserving potency and continence. Aim: The aim of this study was to identify the radiological and clinical parameters that can predict the risk of extraprostatic extension (EPE) for a specific site of the prostate. Predictive models and multiparametric magnetic resonance imaging (mpMRI) data from patients qualified for RP were compared. Material and methods: The study included 61 patients who underwent laparoscopic RP. mpMRI preceded transrectal systematic and cognitive fusion biopsy. Martini, Memorial Sloan-Kettering Cancer Center (MSKCC), and Partin Tables nomograms were used to assess the risk of EPE. The area under the curve (AUC) was calculated for the models and compared. Univariate and multivariate logistic regression analyses were used to determine the combination of variables that best predicted EPE risk based on final histopathology. Results: The combination of mpMRI indicating or suspecting EPE (odds ratio (OR) = 7.49 (2.31–24.27), p < 0.001) and PSA ≥ 20 ng/mL (OR = 12.06 (1.1–132.15), p = 0.04) best predicted the risk of EPE for a specific side of the prostate. For the prediction of ipsilateral EPE risk, the AUC for Martini’s nomogram vs. mpMRI was 0.73 (p < 0.001) vs. 0.63 (p = 0.005), respectively (p = 0.131). The assessment of a non-specific site of EPE by MSKCC vs. Partin Tables showed AUC values of 0.71 (p = 0.007) vs. 0.63 (p = 0.074), respectively (p = 0.211). Conclusions: The combined use of mpMRI, the results of the systematic and targeted biopsy, and prostate-specific antigen baseline can effectively predict ipsilateral EPE (pT3 stage).

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.

Prostate MRI prior to radical prostatectomy: effects on nerve sparing and pathological margin status

OBJECTIVES

The aim of this study was to assess the positive surgical margin (PSM) and nerve sparing (NS) rates in patients who underwent prostate MRI (pMRI) prior to radical prostatectomy (RP) and compare them with matched, nonimaged control RP patients.

METHODS

We identified 204 men who underwent preoperative pelvic MRI (pelMRI), of whom 176 (86.3%) underwent pMRIs, within 60 days of RP, and compared them (1:1) with a nonim-aged control group matched by surgeon, age, race, body mass index (BMI), prostate-specific antigen (PSA), pathological Gleason score, prostate specimen weight, and RP year.

RESULTS

The rates of nonfocal extracapsular extension (nfECE) on RP pathology in the MRI and control groups were similar. PSM rates were lower in the MRI group (13.7% vs 19.3%; P=0.14), but the difference did not meet statistical significance; this was also the case in patients with nfECE on RP pathology (27.7% vs 39.5%; P=0.3). NS rates were similar between groups. In the MRI group, 54 (26.5%) patients had an MRI suspicious for nfECE; their PSM rate (20.4%) was higher than that of patients with an MRI not suspicious for nfECE (11.3%; P=0.11), but the difference lacked statistical significance; the former group had significantly lower rates of NS. Limitations of the study include sample power and nonuniform heeding of MRI results by each surgeon.

CONCLUSION

MRI did not significantly decrease the rates of PSM, including in the subset of patients with nfECE on final pathology. Even wider resection may be necessary in patients with MRIs suggesting locally-advanced disease. Studies with greater power are needed.

Impact of the extent of extraprostatic extension defined by Epstein's method in patients with negative surgical margins and negative lymph node invasion

BACKGROUND

To assess the impact of the degree of extraprostatic extension (EPE) on biochemical recurrence (BCR) and utility of the original Epstein's criteria to define EPE in a cohort of pT3aN0 without positive surgical margin (PSM).

METHODS

A two-center retrospective analysis was performed on data from 490 pT3aN0 patients who underwent radical prostatectomy between 2000 and 2012. Patients with neoadjuvant and/or adjuvant therapy, detectable PSA and PSM were excluded. Our pathologists used Epstein's criteria to report the degree of EPE. When pathology reports did not reflect the terms 'focal' or 'established' (non-focal), slides were analyzed by a single genitourinary pathologist for final evaluation. The end point was defined by BCR.

RESULTS

Selection criteria yielded 247 patients. Mean follow-up was 56.3±4.6 months; mean age at surgery was 62.5 years. Sixty-one (24.7%) patients experienced BCR during follow-up. Patients with focal extension had a 5-year recurrence-free survival of 89% versus 80% for those with non-focal extension (P=0.0018). In multivariate analysis, both pathologic Gleason score (hazard ratio 2.5; 95% confidence interval 1.4-4.5; P=0.002) and the extent of EPE (hazard ratio 1.8; 95% confidence interval 1.1-3.5; P=0.029) were significant predictors of BCR.

CONCLUSIONS

The extent of EPE is an independent predictor of BCR in pT3aN0 prostate cancer without PSM. This study reinforces the utility of the subjective Epstein approach already adopted by most pathologists for quantification of the extent of EPE.

Association of Anterior and Lateral Extraprostatic Extensions with Base-Positive Resection Margins in Prostate Cancer

Introduction

Positive surgical margins (PSM) detected in the radical prostatectomy specimen increase the risk of biochemical recurrence (BCR). Still, with formidable number of patients never experiencing BCR in their life, the reason for this inconsistency has been attributed to the artifacts and to the spontaneous regression of micrometastatic site. To investigate the origin of margin positive cancers, we have looked into the influence of extraprostatic extension location on the resection margin positive site and its implications on BCR risk.

Materials & Methods

The clinical information and follow-up data of 612 patients who had extraprostatic extension and positive surgical margin at the time of robot assisted radical prostatectomy (RARP) in the single center between 2005 and 2014 were modeled using Fine and Gray’s competing risk regression analysis for BCR. Extraprostatic extensions were divided into categories according to location as apex, base, anterior, posterior, lateral, and posterolateral. Extraprostatic extensions were defined as presence of tumor beyond the borders of the gland in the posterior and posterolateral regions. Tumor admixed with periprostatic fat was additionally considered as having extraprostatic extension if capsule was vague in the anterior, apex, and base regions. Positive surgical margins were defined as the presence of tumor cells at the inked margin on the inspection under microscopy. Association of these classifications with the site of PSM was evaluated by Cohen’s Kappa analysis for concordance and logistic regression for the odds of apical and base PSMs.

Results

Median follow-up duration was 36.5 months (interquartile range[IQR] 20.1–36.5). Apex involvement was found in 158 (25.8%) patients and base in 110 (18.0%) patients. PSMs generally were found to be associated with increased risk of BCR regardless of location, with BCR risk highest for base PSM (HR 1.94, 95% CI 1.40–2.68, p<0.001) after adjusting for age, initial prostate-specific antigen, pathologic Gleason score, and pathologic T stage in the multivariate model. Logistic regression for PSM site revealed no significant correlation of apex PSM with extraprostatic extension location, while base PSM was associated with increased odds of anterior (OR 2.513, 95% CI 1.425–4.430, p = 0.001) and lateral (OR 2.715, 95% CI 1.735–4.250, p<0.001) extraprostatic extension.

Conclusion

Extension into the extraprostatic tissue on some specific locations do not share the same recur risk due to the different anatomical structures surrounding the organ. Anterior and lateral EPEs are prone to leave PSM on the base of the prostate, probably because of the lack of anatomical barricades slowing down the direct invasion process. More study on the pattern of spread of the tumors found to have extraprostatic extension is suggested for optimal planning of the operation extent and of the adjuvant radiotherapy.

Prevalence and risk factors of contralateral extraprostatic extension in men undergoing radical prostatectomy for unilateral disease at biopsy: A global multi-institutional experience

INTRODUCTION

We assessed the incidence of contralateral prostate cancer (cPCa), contralateral EPE (cEPE) and contralateral positive surgical margins (cPSM) in patients diagnosed preoperatively with unilateral prostate cancer and evaluated risk factors predictive of contralateral disease extension.

METHODS

The occurrence of cPCa, cEPE and cPSM and the side-specific nerve-sparing technique performed were collected postoperatively from 327 men diagnosed with unilateral prostate cancer at biopsy. Parameters, such as the localization, proportion, and percentage of cancer in positive cores, were prospectively collected.

RESULTS

Overall, 50.5% of patients had bilateral disease, and were at higher risk when associated with a positive biopsy core at the apex (p = 0.016). The overall incidence of ipsilateral EPE and cEPE were 21.4% and 3.4%, respectively (p < 0.001). Compared to cPCa, ipsilateral disease was at an almost 4-fold higher risk of extending out of the prostate (p < 0.001). None of the criteria tested were identified as useful predictors for cEPE. The low incidence of cEPE in our cohort could limit our ability to detect significance. The overall incidence of ipsilateral PSM and cPSM were 15.3% and 5.8%, respectively (p < 0.001). More aggressive nerve-sparing was not associated with a higher incidence of PSM. Prostate sides selected for more aggressive nerve-sparing were associated with younger patients (p < 0.001), a smaller prostate (p = 0.006), and a lower percentage of cancer in biopsy material (p = 0.008).

CONCLUSION

Although the risk of cPCa is high in patients diagnosed with unilateral prostate cancer at biopsy, the risk of cEPE and cPSM is low, yet not insignificant. Contralateral aggressive nerve-sparing should be used with caution and should not compromise oncological outcome.