Utility of intraoperative frozen section analysis of surgical margins in region of neurovascular bundles at radical prostatectomy

Intraoperative pathology consultation during urological surgery: Impact on final margin status and pitfalls of frozen section diagnosis

Despite recent improvements in diagnostic and surgical techniques in urological oncology, positive resection margin remains a significant concern for surgeons. Meanwhile, intraoperative pathology consultation with frozen section assessment (FSA), particularly for histological diagnosis of the lesions incidentally found or enlarged or sentinel lymph nodes, generally provides critical information which enables immediate decision making for optimal patient care. The intraoperative evaluation of surgical margins is also often requested, although there are some differences in its application between institutions and surgeons. Importantly, it remains to be determined whether intraoperative FSA indeed contributes to reducing the risk of final positive margins and thereby improving long-term patient outcomes. This review summarizes available data indicating the potential impact of FSA at the surgical margins during urological surgeries, including radical or partial cystectomy, partial nephrectomy, radical prostatectomy, penectomy, and orchiectomy. The accuracy and pitfalls of the intraoperative consultation/FSA diagnosis are also discussed.

Intraoperative assessment and reporting of radical prostatectomy specimens to guide nerve-sparing surgery in prostate cancer patients (NeuroSAFE)

Aims

Radical prostatectomy for prostate cancer is frequently complicated by urinary incontinence and erectile dysfunction. Nerve‐sparing surgery reduces the risk of postoperative complications and can be optimised by the use of intraoperative frozen sections of the adjacent neurovascular structure (NeuroSAFE). The aims of this study were to evaluate the pathological outcomes of the NeuroSAFE technique and to develop a comprehensive algorithm for intraoperative clinical decision‐making.

Methods and results

Between September 2018 and May 2019, 491 NeuroSAFE procedures were performed in 258 patients undergoing radical prostatectomy; 74 of 491 (15.1%) NeuroSAFE specimens had positive surgical margins. As compared with the corresponding paraffin sections, NeuroSAFE had a positive predictive value and negative predictive value of 85.1% and 95.4%, respectively. In 72.2% of secondary neurovascular bundle resections prompted by a NeuroSAFE positive surgical margin, no tumour was present. These cases more often had a positive surgical margin of ≤1 mm (48.7% versus 20.0%; P = 0.001) and only one positive slide (69.2% versus 33.3%; P = 0.008). None of the nine patients with Gleason pattern 3 at the surgical margin, a positive surgical margin length of ≤1 mm and one positive slide had tumour in the secondary resection.

Conclusions

This study provides a systematic reporting template for pathological intraoperative NeuroSAFE evaluation, supporting intraoperative clinical decision‐making and comparison between prostate cancer operation centres.

"Real-time" Assessment of Surgical Margins During Radical Prostatectomy: State-of-the-Art

Histopathologic examination of the pathologic specimens using hematoxylin & eosin stains represents the backbone of the modern pathology. It is time-consuming; thus, "real-time" assessment of prostatic and periprostatic tissue has gained special interest in the diagnosis and management of prostate cancer. The current study focuses on the review of the different available techniques for "real-time" evaluation of surgical margins during radical prostatectomy (RP). We performed a comprehensive search of the Medline database to identify all the articles discussing "real-time" or intraoperative assessment of surgical margins during RP. Several filters were applied to the search to include only English articles performed on human subjects and published between January 2000 and March 2019. The search revealed several options for pathologic assessment of surgical margins including intraoperative frozen sections, confocal laser endomicroscopy, optical spectroscopy, photodynamic diagnosis, optical coherence tomography, multiphoton microscopy, structured illumination microscopy, 3D augmented reality, and ex vivo fluorescence confocal microscope. Frozen section represents the gold standard technique for real-time pathologic examinations of surgical margins during RP; however, several other options showed promising results in the initial clinical trials, and considering the rapid development in the field of molecular and cellular imaging, some of these options may serve as an alternative to frozen section.

NeuroSAFE robot-assisted laparoscopic prostatectomy versus standard robot-assisted laparoscopic prostatectomy for men with localised prostate cancer (NeuroSAFE PROOF): protocol for a randomised controlled feasibility study

INTRODUCTION

Robot-assisted laparoscopic prostatectomy (RALP) offers potential cure for localised prostate cancer but is associated with considerable toxicity. Potency and urinary continence are improved when the neurovascular bundles (NVBs) are spared during a nerve spare (NS) RALP. There is reluctance, however, to perform NS RALP when there are concerns that the cancer extends beyond the capsule of the prostate into the NVB, as NS RALP in this instance increases the risk of a positive surgical margin (PSM). The NeuroSAFE technique involves intraoperative fresh-frozen section analysis of the posterolateral aspect of the prostate margin to assess whether cancer extends beyond the capsule. There is evidence from large observational studies that functional outcomes can be improved and PSM rates reduced when the NeuroSAFE technique is used during RALP. To date, however, there has been no randomised controlled trial (RCT) to substantiate this finding. The NeuroSAFE PROOF feasibility study is designed to assess whether it is feasible to randomise men to NeuroSAFE RALP versus a control arm of 'standard of practice' RALP.

METHODS

NeuroSAFE PROOF feasibility study will be a multicentre, single-blinded RCT with patients randomised 1:1 to either NeuroSAFE RALP (intervention) or standard RALP (control). Treatment allocation will occur after trial entry and consent. The primary outcome will be assessed as the successful accrual of 50 men at three sites over 15 months. Secondary outcomes will be used to aid subsequent power calculations for the definitive full-scale RCT and will include rates of NS; PSM; biochemical recurrence; adjuvant treatments; and patient-reported functional outcomes on potency, continence and quality of life.

ETHICS AND DISSEMINATION

NeuroSAFE PROOF has ethical approval (Regional Ethics Committee reference 17/LO/1978). NeuroSAFE PROOF is supported by National Institute for Healthcare Research Research for Patient Benefit funding (NIHR reference PB-PG-1216-20013). Findings will be made available through peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03317990.

The impact on oncological outcomes after radical prostatectomy for prostate cancer of converting soft tissue margins at the apex and bladder neck from tumour-positive to -negative

OBJECTIVES

To assess the impact of conversion from histologically positive to negative soft tissue margins at the apex and bladder neck on biochemical recurrence-free survival (BCRFS) and distant metastasis-free survival (DMFS) after radical prostatectomy (RP) for prostate cancer.

MATERIALS AND METHODS

The records of 2 013 patients who underwent RP and intra-operative frozen section (IFS) analysis between July 2007 and June 2016 were reviewed. IFS analysis of the urethra and bladder neck was performed, and if malignant or atypical cells remained, further resection with the aim of achieving histological negativity was carried out. Patients were divided into three groups according to the findings: those with a negative surgical margin (NSM), a positive surgical margin converted to negative (NCSM) and a persistent positive surgical margin (PSM).

RESULTS

Among the 2 013 patients, rates of NSMs, NCSMs and PSMs were 75.1%, 4.9%, and 20.0%, respectively. The 5-year BCRFS rates of patients with NSMs, NCSMs and PSMs were 89.6%, 85.1% and 57.1%, respectively (P < 0.001). In both pathological (p)T2 and pT3 cancers, the 5-year BCRFS rate for patients with NCSMs was similar to that for patients with NSMs, and higher than for patients with PSMs. The 7-year DMFS rates of patients with NSMs, NCSMs and PSMs were 97.8%, 99.1% and 89.4%, respectively (P < 0.001). Among patients with pT3 cancers, the 7-year DMFS rate was significantly higher in the NCSM group than in the PSM group (98.0% vs 86.7%; P = 0.023), but not among those with pT2 cancers (100% vs 96.9%; P = 0.616). The 5-year BCRFS rate for the NCSM group was not significantly different from that of the NSM group among the patients with low- (96.3% vs 95.8%) and intermediate-risk disease (91.1% vs 82.8%), but was lower than that of the NSM group among patients in the high-risk group (73.2% vs 54.7%).

CONCLUSIONS

Conversion of the soft tissue margin at the prostate apex and bladder neck from histologically positive to negative improved the BCRFS and DMFS after RP for prostate cancer; however, the benefit of conversion was not apparent in patients in the high-risk group.

Prostate Cancer Detection Using Composite Impedance Metric

Prostate cancer (PCa) recurrences are often predicted by assessing the status of surgical margins (SM)- positive surgical margins (PSM) increase the chances of biochemical recurrence by 2-4 times which may lead to PCa recurrence. To this end, an electrical impedance acquisition system with a microendoscopic probe was employed in an ex-vivo study of human prostates. This system measures the tissue bioimpedance over a range of frequencies (1 kHz to 1MHz), and computes a number of Composite Impedance Metrics (CIM). A classifier trained using CIM data can be used to classify tissue as benign or cancerous. The system was used to collect the impedance spectra from 14 excised prostates, which were obtained from men undergoing radical prostatectomy, for a total of 23 cancerous and 53 benign measurements. The data revealed statistically significant (p < 0.05) differences in the impedance properties of the benign and tumorous tissues, and among the measurements taken on the apical, base, and lateral surface of the prostate. Further, in the leave-one-patient-out cross validation, a maximum predictive accuracy of 90.79% was achieved by combining high frequency CIM phase data to train a support vector machine classifier with a radial basis function kernel. The observations are consistent with the physiology and morphology of benign and malignant prostate tissue. CIMs were found to be an effective tool in distinguishing benign from cancerous tissues.

Clinical benefits of frozen section assessment during urological surgery: Does it contribute to improving surgical margin status and patient outcomes as previously thought?

Despite significant advances in patient selection as well as surgical technique over the past few decades, it is still not uncommon for patients with urological malignancy and positive surgical margins to be observed. Meanwhile, intraoperative pathology consultation with frozen section assessment, which generally provides useful information for the optimal procedure, has been widely utilized for the assessment of surgical margins during urological surgeries. Thus, it remains unanswered whether intraoperative frozen section assessment has an impact on final surgical margin status as well as long-term oncological outcomes. The present review summarizes and discusses available data assessing the utility of frozen section assessment of the surgical margins during urological surgeries, such as radical prostatectomy, partial nephrectomy and radical cystectomy. The current findings suggest that select patients might benefit from the routine frozen section assessment.

Multiparametric magnetic resonance imaging and frozen-section analysis efficiently predict upgrading, upstaging, and extraprostatic extension in patients undergoing nerve-sparing robotic-assisted radical prostatectomy

To evaluate the role of multiparametric magnetic resonance imaging (mpMRI) in predicting upgrading, upstaging, and extraprostatic extension in patients with low-risk prostate cancer (PCa). MpMRI may reduce positive surgical margins (PSM) and improve nerve-sparing during robotic-assisted radical prostatectomy (RARP) for localized prostate cancer PCa.This was a retrospective, monocentric, observational study. We retrieved the records of patients undergoing RARP from January 2012 to December 2013 at our Institution. Inclusion criteria were: PSA <10 ng/mL; clinical stage <T3a; biopsy Gleason score <7; prostate mpMRI performed preoperatively at our Institution; intraoperative FSA of the posterolateral aspects of the specimen.All the identified lesions were scored according to the Prostate Imaging Reporting and Data System (PIRADS). We considered the lesion with the highest PIRADS score as index lesion. All the included patients underwent nerve-sparing RARP. During surgery, the specimen was sent for FSA of the posterolateral aspects. The surgeon, according to the localization scheme provided by the mpMRI, inked the region of the posterolateral aspect of the prostate that had to be submitted to FSA.We evaluated association between clinical features and PSM, upgrading, upstaging, and presence of unfavorable disease.Two hundred fifty-four patients who underwent nerve-sparing RARP were included. PSM rate was 29.13% and 15.75% at FSA and final pathology respectively. Interestingly, the use of FSA reduced PSM rate in pT3 disease (25.81%). Higher PIRADS scores demonstrated to be related to high probability of upgrading and upstaging. This significativity remains even when considering PIRADS 2-3 versus 4 versus 5 and PIRADS 2-3 versus 4-5. Also PSM at FSA were associated with higher probability of upgrading and upstaging.PIRADS score and FSA resulted to be strictly related to grading and staging, thus being able to predict upgrading and/or upstaging at final pathology.

Light Reflectance Spectroscopy to Detect Positive Surgical Margins on Prostate Cancer Specimens

PURPOSE

Intraoperative frozen section analysis is not routinely performed to determine positive surgical margins at radical prostatectomy due to time requirements and unproven clinical usefulness. Light reflectance spectroscopy, which measures light intensity reflected or backscattered from tissues, can be applied to differentiate malignant from benign tissue. We used a novel light reflectance spectroscopy probe to evaluate positive surgical margins on ex vivo radical prostatectomy specimens and correlate its findings with pathological examination.

MATERIALS AND METHODS

Patients with intermediate to high risk disease undergoing radical prostatectomy were enrolled. Light reflectance spectroscopy was performed on suspected malignant and benign prostate capsule immediately following organ extraction. Each light reflectance spectroscopy at 530 to 830 nm was analyzed and correlated with pathological results. A regression model and forward sequential selection algorithm were developed for optimal feature selection. Eighty percent of light reflectance spectroscopy data were selected to train a logistic regression model, which was evaluated by the remaining 20% data. This was repeated 5 times to calculate averaged sensitivity, specificity and accuracy.

RESULTS

Light reflectance spectroscopy analysis was performed on 17 ex vivo prostate specimens, on which a total of 11 histologically positive and 22 negative surgical margins were measured. Two select features from 700 to 830 nm were identified as unique to malignant tissue. Cross-validation when performing the predictive model showed that the optical probe predicted positive surgical margins with 85% sensitivity, 86% specificity, 86% accuracy and an AUC of 0.95.

CONCLUSIONS

Light reflectance spectroscopy can identify positive surgical margins accurately in fresh ex vivo radical prostatectomy specimens. Further study is required to determine whether such analysis may be used in real time to improve surgical decision making and decrease positive surgical margin rates.

Number of positive preoperative biopsy cores is a predictor of positive surgical margins (PSM) in small prostates after robot-assisted radical prostatectomy (RARP)

OBJECTIVE

To determine the impact of prostate size on positive surgical margin (PSM) rates after robot-assisted radical prostatectomy (RARP) and the preoperative factors associated with PSM.

PATIENTS AND METHODS

In all, 1229 men underwent RARP by a single surgeon, from 2005 to August of 2013. Excluded were patients who had transurethral resection of the prostate, neoadjuvant therapy, clinically advanced cancer, and the first 200 performed cases (to reduce the effect of learning curve). Included were 815 patients who were then divided into three prostate size groups: <31 g (group 1), 31-45 g (group 2), >45 g (group 3). Multivariate analysis determined predictors of PSM and biochemical recurrence (BCR).

RESULTS

Console time and blood loss increased with increasing prostate size. There were more high-grade tumours in group 1 (group 1 vs group 2 and group 3, 33.9% vs 25.1% and 25.6%, P = 0.003 and P = 0.005). PSM rates were higher in prostates of <45 g with preoperative PSA levels of >20 ng/dL, Gleason score ≥7, T3 tumour, and ≥3 positive biopsy cores. In group 1, preoperative stage T3 [odds ratio (OR) 3.94, P = 0.020] and ≥3 positive biopsy cores (OR 2.52, P = 0.043) were predictive of PSM, while a PSA level of >20 ng/dL predicted the occurrence of BCR (OR 5.34, P = 0.021). No preoperative factors predicted PSM or BCR for groups 2 and 3.

CONCLUSION

A preoperative biopsy with ≥3 positive cores in men with small prostates predicts PSM after RARP. In small prostates with PSM, a PSA level of >20 ng/dL is a predictor of BCR. These factors should guide the choice of therapy and indicate the need for closer postoperative follow-up.

Safe-R: a novel score, accounting for oncological safe nerve-sparing at radical prostatectomy for localized prostate cancer

OBJECTIVES

The objectives of the study were to describe a novel score (safe-R), combining information on surgical margin status (SM) and extend of nerve-sparing (NS) applicable for all patients undergoing radical prostatectomy (RP), and to test the impact of our frozen-section navigated nerve-sparing approach (NeuroSAFE) on safe-R score.

METHODS

We retrospectively analyzed 9,635 RPs performed at our center between 2002 and 2011. Of these, 47 % were conducted with NeuroSAFE. Proportions of NS and SM status were assessed. Subsequently, a score for oncological safe NS (safe-R) was developed; Safe-R was categorized as 3 (for negative SM and bilateral NS), 2 (for negative SM and unilateral NS), 1 (for negative SM without NS), and 0 (for patients with positive SM), respectively. The impact of NeuroSAFE on safe-R was analyzed by chi-square test and confirmed by multinomial logistic regression, adjusting for preoperative risk factors.

RESULTS

Applying NeuroSAFE resulted in enhanced safe-R score, indicating lower rates of positive SM and higher rates of NS, across all risk categories (all p < 0.001). For example in high-risk patients, NeuroSAFE resulted in lower proportions of safe-R 0 (27.6 vs. 33.6 %) and higher proportions of safe-R 3 (32.4 vs. 17.1 %, p < 0.001). Linkage between the NeuroSAFE approach and safe-R was confirmed after multinomial logistic adjustment for preoperative risk factors. All results were confirmed in a propensity-matched cohort (matched for preoperative risk factors and year of surgery, data not shown).

CONCLUSION

Safe-R represents a novel tool to assess and report on oncological safe nerve-sparing in RP. NeuroSAFE is associated with enhanced safe-R scores.

Impiego Dell'esame Estemporaneo al Congelatore per la Valutazione dei Margini Chirurgici in Corso di Prostatectomia Radicale

Introduction

At present there is no consensus on the use of frozen sections (FS) during radical prostatectomy. Several groups have proposed the benefit of FS although the studies differ widely in sampling methods and sites where FS were taken. This study aims to evaluate the usefulness and reliability of standard assessment of FS in multiple sites during radical prostatectomy.

Methods

During open radical prostatectomy in all patients we sampled tissue from the urethral stump, the neurovascular bundles, the Denonvillier fascia and the bladder neck after removing the prostate. Where FS showed positive margins, further periprostatic tissue was resected from the prostatic bed until negative margins were achieved. The results of FS were compared with margin status of final pathology.

Results

From 1998 to 2004 we performed FS during 250 consecutive open radical prostatectomies (104 nerve sparing procedures). 66 patients had positive FS (26.4%) and 53 patients had positive surgical margins at final pathology (21.2%). All patients with positive FS had negative margins when further tissue was resected in the prostatic bed. During nerve sparing procedures positive FS were found in 14 patients. In these cases the procedure was converted into standard prostatectomy by resecting the neurovascular bundles. Sensibility and specificity were both 90%. Positive and negative predictive values were respectively 72% and 97%.

Conclusions

Standard assessment of FS in multiple sites during radical prostatectomy achieved sensibility and specificity as high as 90%. Although the resection of urethral stump and tissue close to the neurovascular bundles could compromise functional results, standard assessment of FS in multiple sites could help the surgeon to reduce the positive surgical margins, to monitor the oncological safety of a nerve sparing procedure and to improve the pathological staging.

Quantitative, spectrally-resolved intraoperative fluorescence imaging

Intraoperative visual fluorescence imaging (vFI) has emerged as a promising aid to surgical guidance, but does not fully exploit the potential of the fluorescent agents that are currently available. Here, we introduce a quantitative fluorescence imaging (qFI) approach that converts spectrally-resolved data into images of absolute fluorophore concentration pixel-by-pixel across the surgical field of view (FOV). The resulting estimates are linear, accurate, and precise relative to true values, and spectral decomposition of multiple fluorophores is also achieved. Experiments with protoporphyrin IX in a glioma rodent model demonstrate in vivo quantitative and spectrally-resolved fluorescence imaging of infiltrating tumor margins for the first time. Moreover, we present images from human surgery which detect residual tumor not evident with state-of-the-art vFI. The wide-field qFI technique has broad implications for intraoperative surgical guidance because it provides near real-time quantitative assessment of multiple fluorescent biomarkers across the operative field.

Detection of prostate cancer by radio-frequency near-field spectroscopy in radical prostatectomy ex vivo specimens

BACKGROUND

The aim of radical prostatectomy (RP) is the complete removal of the prostate gland with negative surgical margins. The presence of cancer at the surgical margin is associated with higher probability of disease progression. Current methods of intraoperative margin assessment are inaccurate or time-consuming.The study goal was to evaluate the ability of a novel device (Dune Medical Devices) to differentiate between cancer and BPH.

METHODS

A total of 49 patients undergoing RP in four medical centers between November 2007 and May 2008 were enrolled in this study.The device was applied to numerous intra- and extra-capsular sites of freshly excised RP specimens. Measurement sites were accurately marked and analyzed histologically. The ability of the device to differentiate between malignant and nonmalignant sites was assessed.

RESULTS

A total of 15,156 measurements from 45 patients were analyzed. Differentiation of the intra-capsular malignant sites from extra-capsular nonmalignant sites (bladder neck and apex regions) depends on the cancer feature size. Differentiation was achieved with sensitivity and specificity of 93.6 (95% confidence interval (CI): 88-98) and 94.1 (95% CI: 93-95), respectively, at feature sizes at or >0.8 mm in diameter. The device was able to discriminate between all intra-capsular malignant (with feature sizes down to a few cells) and nonmalignant measurement sites, with sensitivity and specificity of 80.8 (95% CI: 73-87) and 68.4 (95% CI: 67-69), respectively.

CONCLUSIONS

First results from a radio-frequency near-field spectroscopy sensor look promising for differentiation between cancer and benign prostate tissue. The sensor's dimensions (radius of ~ 1 mm) and design enable use in open, laparoscopic and robotic RP to evaluate the surgical margins intraoperatively.

Neurovascular structure-adjacent frozen-section examination (NeuroSAFE) increases nerve-sparing frequency and reduces positive surgical margins in open and robot-assisted laparoscopic radical prostatectomy: experience after 11,069 consecutive patients

BACKGROUND

Intraoperative frozen-section analysis allows real-time histologic assessment of surgical margins (SMs) and identification of candidates for nerve-sparing (NS) procedures.

OBJECTIVE

To examine the efficacy and oncologic safety of a systematic neurovascular structure-adjacent frozen-section examination (NeuroSAFE) during NS radical prostatectomy (RP).

DESIGN, SETTING, AND PARTICIPANTS

From January 2002 to June 2011, 11 069 consecutive RPs were performed at the University Medical Center Hamburg-Eppendorf. Of these, 5392 (49%) were conducted with NeuroSAFE.

SURGICAL PROCEDURE

Our NeuroSAFE approach included the whole laterorectal circumference of the prostate to determine the SM status of the complete neurovascular tissue-corresponding prostatic surface.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The impact of NeuroSAFE on NS frequency, SM status, and biochemical recurrence (BCR) was analyzed by chi-square test, and by Kaplan-Meier analyses in propensity score-based matched cohorts.

RESULTS AND LIMITATIONS

Positive SMs (PSMs) were detected in 1368 (25%) NeuroSAFE RPs, leading to a secondary resection of the ipsilateral neurovascular tissue. Secondary wide resection resulted in conversion to a definitive negative SM (NSM) status in 1180 (86%) patients. In NeuroSAFE RPs, frequency of NS was significantly higher (all stages: 97% vs 81%; pT2: 99% vs 92%; pT3a: 94% vs 72%; pT3b: 88% vs 40%; p<0.0001) and PSM rates were significantly lower (all stages: 15% vs 22%; pT2: 7% vs 12%; pT3a: 21% vs 32%; p<0.0001) than in the matched non-NeuroSAFE RPs. In propensity score-based comparisons, NeuroSAFE had no negative impact on BCR (pT2, p=0.06; pT3a, p=0.17, pT3b, p=0.99), and BCR-free survival of patients with conversion to NSM did not differ significantly from patients with primarily NSM (pT2, p=0.16; pT3, p=0.26). The accuracy of our NeuroSAFE approach was 97% with a false-negative rate of 2.5%. The major limitations of this study are its retrospective nature and relatively short follow-up.

CONCLUSIONS

NeuroSAFE enables real-time histologic monitoring of the oncologic safety of a NS procedure. Systematic NeuroSAFE significantly increases NS frequencies and reduces PSMs. Patients with a NeuroSAFE-detected PSM could be converted to a prognostically more favorable NSM status by secondary wide resection.

Label-free high-resolution imaging of prostate glands and cavernous nerves using coherent anti-Stokes Raman scattering microscopy

A custom built coherent anti-Stokes Raman scattering (CARS) microscope was used to image prostatic glands and nerve structures from 17 patients undergoing radical prostatectomy. Imaging of glandular and nerve structures showed distinctive cellular features that correlated to histological stains. Segmentation of cell nucleus was performed to establish a cell feature-based model to separate normal glands from cancer glands. In this study, we use a single parameter, average cell neighbor distance based on CARS imaging, to characterize normal and cancerous glandular structures. By combining CARS with our novel classification model, we are able to characterize prostate glandular and nerve structures in a manner that potentially enables real-time, intra-operative assessment of surgical margins and neurovascular bundles. As such, this method could potentially improve outcomes following radical prostatectomy.

Preoperative nomograms for predicting extracapsular extension in Korean men with localized prostate cancer: a multi-institutional clinicopathologic study

We developed a nomogram to predict the probability of extracapsular extension (ECE) in localized prostate cancer and to determine when the neurovascular bundle (NVB) may be spared. Total 1,471 Korean men who underwent radical prostatectomy for prostate cancer between 1995 and 2008 were included. We drew nonrandom samples of 1,031 for nomogram development, leaving 440 samples for nomogram validation. With multivariate logistic regression analyses, we made a nomogram to predicts the ECE probability at radical prostatectomy. Receiver operating characteristic (ROC) analyses were also performed to assess the predictive value of each variable alone and in combination. The internal validation was performed from 200 bootstrap re-samples and the external validation was also performed from the another cohort. Overall, 314 patients (30.5%) had ECE. Age, Prostate specific antigen (PSA), biopsy Gleason score, positive core ratio, and maximum percentage of biopsy tumor were independent predictors of the presence of ECE (all P values <0.05). The nomogram predicted ECE with good discrimination (an area under the ROC curve of 0.777). Our nomogram allows for the preoperative identification of patients with an ECE and may prove useful in selecting patients to receive nerve sparing radical prostatectomy.

Value of frozen section biopsies during radical prostatectomy: significance of the histological results

PURPOSE

To review the evidence about frozen sections during radical prostatectomy (RP) and its ability to decrease the incidence of positive margins, the impact on PSA postoperatively and the significance of residual benign prostatic cells after prostatectomy.

METHODS

The information for this review was compiled by searching the Pubmed database. We used Mesh Terms "Prostatectomy" and "Prostatic Neoplasms" and we added "frozen sections" and/or "hyperplasic cells" and/or "benign cells" and/or "positive margins". Furthermore, we review the articles referenced in those studies and editorials letters.

RESULTS

Several groups have studied the performance of frozen section during RP to try and assess the risk of positive margins intraoperatively. The controversial sites where they should be performed are the apex, the dorsolateral zones and the bladder neck. They have been performed routinely or when the surgeon decides it, depending on the preoperative or intraoperative findings.

CONCLUSIONS

At the present time there is no standardisation in the number, the site and the type of patient where this procedure should be done. The improvement in functional outcomes and biochemical control is not proven.

[Frozen section in urological oncology]

The indications of Frozen section diagnosis (FS) in surgery due to urologic neoplasia are quite specific, and this explains the fact that they amount to a mere 7.3% of the FSs performed in general hospitals. This also makes the knowledge of their usefulness necessary, and thus we are submitting the present review. Generally speaking, FS is not warranted to identify the nature of a tumoral mass, with the following exceptions: (1) Renal masses of a doubtf ul parenchymal origin, or in the urinary tract: (2) Intesticular neoplasias,when the possibility of a conservative treatment arises; (3) Determination of the presence of a prostate adenocarcinoma in an organ donor with high serum PSA; but even in these circumstances its need is widely controversial. Intraoperative determination of surgical margins is particularly useful in: (1) Partial nephrectomies (it may be limited to inspection after dyeing the margin with Indian ink--bed freezing is very seldom needed); (2) Urethral margins in women with total cystectomies and orthotopic substitution; (3) In partial penectomies (always studying the urethral margin and the cavernosal and spongIosal corpora margins). The study of the nodes is a widely debated issue, and except for those cases in which unexpectedly increased node size is found, systematic FS is indicated neither of the bladder nor of the prostate. The situation regarding penis carcinoma is different, as in the groups with intermediate and high risk of node metastasis, even though there is around 16%-18% of false negatives FS is recommended, particularly of radioisotope-marked sentinel nodes.

Nerve Advancement with End-to-End Reconstruction after Partial Neurovascular Bundle Resection:A Feasibility Study

BACKGROUND AND PURPOSE

It is clear that some patients with prostate cancer require a total or partial neurovascular bundle (NVB) resection for oncologic safety to be guaranteed. Nerve grafting is an alternative for these patients to maintain erectile function; however, we report on a feasible option where the NVB is released, and both terminal nerve fibers are approximated; this is the "nerve advancement technique (NAT)."

PATIENTS AND METHODS

Since 2005, a total of 215 men aged 48 to 70 years (mean 59 years) with a Sexual Health Inventory for Men (SHIM) score of 22 have undergone robotic radical prostatectomy for cancer. We selected prospectively seven men to have NAT performed because of clinical high-risk criteria (serum prostate specific antigen [PSA] concentration >20 mg/dL, Gleason score = 8, and stage cT(2c) or higher), intraoperative criteria (difficulty separating the tissues around the prostate), and evidence of extracapsular extension (ECE) on magnetic resonance imaging. We performed unilateral partial resection, nerve advancement, and, finally, end-to-end anastomosis in six patients, whereas in one patient, we did a bilateral partial excision. We analyzed the results in terms of oncologic safety (positive surgical margins and PSA) and SHIM score after 18 months of follow-up.

RESULTS

Pathologic examination revealed stage T3 disease in six patients; one had a positive surgical margin. Two patients are receiving salvage radiotherapy for PSA relapse, and five continue to have undetectable PSA concentrations after a median follow-up of 20 months. Five of the seven men recovered erectile potency with or without a phosphodiesterase inhibitor, and their median SHIM score is 18.

CONCLUSIONS

We are encouraged by the initial results of NAT. The procedure may be an alternative for men who require extensive NVB dissection. However, further experience, longer follow-up, and independent trials are necessary.

Frozen Section for the Management of Intraoperatively Detected Palpable Tumor Lesions During Nerve-Sparing Scheduled Radical Prostatectomy

OBJECTIVES

The intraoperative finding of palpable tumor lesions has been described as a contraindication for nerve-sparing (NS) radical prostatectomy (RP). However, its evaluation is subjective. Especially in patients with a strong demand to regain postoperative erectile function, a surgeon might be reluctant to sacrifice neurovascular bundles (NVBs) based on this information. We investigated the use of frozen section (FS) analysis to monitor the safety and efficiency of NS during RP in patients with intraoperatively identified subcapsular tumor lesions.

METHODS

In 83 of 608 patients, who underwent NS-RP, intraoperative FS was performed because of a lesion palpable close to the capsule. A wedge of 4cm in diameter including the lesion was cut off and stained differently for capsule and intraprostatic margin. In case of presence of carcinoma adherent to the capsule, the NVB was resected; otherwise, the NVB remained in situ.

RESULTS

Patients with palpable tumor lesions had pT3 tumors in 36% and 61% had Gleason 4 pattern, compared to 18% and 42% for the control group. Carcinoma was found in 93% of the FS specimens. In 42% of the FS samples, tumor had contact with the capsule and 14% of secondary resected NVB specimens demonstrated a carcinoma invasion. In 52% NVBs could be preserved despite an ipsilateral nodule without negatively affecting the margin status. However, the false-negative rate of the FSs was 6%. Conversely, FSs set the intraoperative decision to remove the NVB in 42% of FS patients, resulting in an additional 36% of negative margins.

CONCLUSIONS

In patients with intraoperatively detected tumor lesions during a NS planned RP, FS objectively supports the decision of secondary NVB resection as well as preservation.

Key issues in handling and reporting radical prostatectomy specimens

CONTEXT

Patients with prostatic adenocarcinoma commonly undergo radical prostatectomy, and it is often difficult and time consuming to handle the resulting specimens and to report the findings. Pathologic information derived from the radical prostatectomy specimen is used for selecting adjuvant therapy, such as radiotherapy and hormone therapy, and for determining a patient's prognosis. The prostate specimen must be handled in a systematic fashion to derive the appropriate prognostic parameters.

OBJECTIVE

To review the prognostic factors of relevance in classifying radical prostatectomy specimens, using the College of American Pathologists categorization system, including a detailed survey of the morphologic-based factors but excluding other factors such as DNA ploidy and novel phenotypic and genotypic markers.

CONCLUSIONS

Gleason score, pathologic stage, and margin status are considered category 1 prognostic factors, which are of proven prognostic significance and are useful in patient management. Factors such as tumor volume (intraglandular extent) and tumor subtype are considered category 2 prognostic factors, which show significant promise but require validation in multivariate analysis. Lymphovascular space invasion is a promising category 3 prognostic factor that needs additional study. Perineural invasion is an almost ubiquitous finding in radical prostatectomy specimens and is considered a category 3 prognostic factor. After prognostic factors have been analyzed at the histologic level, it is critical to report the findings in a clear and unambiguous fashion. The synoptic style of reporting is ideal for describing complex cancer resection specimens. A synoptic report based on an evidence-based checklist, such as the one developed by the College of American Pathologists, effectively communicates complex cancer-related data, such as radical prostatectomy specimen findings. This information is used not only for individual case management with respect to treatment and prognostication but also for purposes such as education, research, quality monitoring, and system planning.

Prognostic factors and reporting of prostate carcinoma in radical prostatectomy and pelvic lymphadenectomy specimens

This paper, based on the activity of the Morphology-Based Prognostic Factors Committee of the 2004 World Health Organization-sponsored International Consultation, describes various methods of handling radical prostatectomy specimens for both routine clinical use and research purposes. The correlation between radical prostatectomy findings and postoperative failure is discussed in detail. This includes issues relating to pelvic lymph node involvement, detected both at the time of frozen section and in permanent sections. Issues of seminal vesicle invasion, including its definition, routes of invasion and relationship to prognosis, are covered in detail. The definition, terminology and incidence of extra-prostatic extension are elucidated, along with its prognostic significance relating to location and extent. Margins of resection are covered in terms of their definition, the etiology, incidence and sites of positive margins, the use of frozen sections to assess the margins and the relationship between margin positivity and prognosis. Issues relating to grade within the radical prostatectomy specimen are covered in depth, including novel ways of reporting Gleason grade and the concept of tertiary Gleason patterns. Tumor volume, tumor location, vascular invasion and perineural invasion are the final variables discussed relating to the prognosis of radical prostatectomy specimens. The use of multivariate analysis to predict progression is discussed, together with proposed modifications to the TNM system. Finally, biomarkers to predict progression following radical prostatectomy are described, including DNA ploidy, microvessel density, Ki-67, neuroendocrine differentiation, p53, p21, p27, Bcl-2, Her-2/neu, E-cadherin, CD44, retinoblastoma proteins, apoptotic index, androgen receptor status, expression of prostate-specific antigen and prostatic-specific acid phosphatase and nuclear morphometry.

Is intraoperative frozen section analysis an efficient way to reduce positive surgical margins?

OBJECTIVES

To assess the accuracy and efficiency of frozen section analysis to detect positive surgical margins (+SMs) during radical prostatectomy.

METHODS

In a consecutive series of 760 patients treated with radical prostatectomy from 1998 to 2002, areas suspicious for +SMs on the surface of the removed prostate were examined by frozen section analysis. In a subset of 520 patients, the surgeon's level of suspicion for +SMs was scored and recorded during radical prostatectomy.

RESULTS

Overall, 259 patients underwent frozen section examination. Of these, 55 patients (21%) had +SMs on permanent section examination compared with 50 (10%) of 501 patients with no frozen section analysis (P <0.005). Cancer was present in 23 (8.9%) frozen section specimens, all of which were confirmed on permanent section analysis. Frozen section examination missed 32 +SMs in 236 patients with negative frozen section results. The sensitivity, specificity, and positive and negative predictive value of frozen section analysis to identify +SMs was 42%, 100%, 100%, and 86%, respectively. However, the sensitivity of frozen section analysis was much lower (23 of 105, 22%) when analyzed for the entire population, including those who did not have frozen section analysis. Among the subset of 520 patients with the level of suspicion recorded, 79 had a +SM on permanent section examination. However, 51 (64%) of these were in patients with no suspicious area in the prostatectomy specimen.

CONCLUSIONS

Although the positive predictive value of frozen section analysis for +SMs is high, the sensitivity is too low to expect that a policy of routine frozen section analysis of suspicious areas will reduce the rate of +SMs substantially.

Laparoscopic Radical Prostatectomy: The Value of Intraoperative Frozen Sections

OBJECTIVE

To examine the clinical and pathological value of intraoperative frozen section (IFS) in patients undergoing laparoscopic radical prostatectomy (L-RPE) for clinically localized prostate cancer.

METHODS

The study includes 198 consecutive cases of L-RPE. After removal of the prostate, a 2-3mm circumferential specimen was obtained from the apical and bladder neck soft-tissue margin and submitted for IFS examination. In cases suspicious for capsular incision (n=57), IFS were taken from the neurovascular bundle/lateral pedicle.

RESULTS

The IFS diagnosis from the apical, bladder neck, and neurovascular bundle/lateral pedicle soft-tissue margins was adenocarcinoma in 12 (6%), 1 (0.5%), and 2 (1%) cases, respectively. Patient age, clinical stage, and mean specimen weight were not associated with cancer at the apical IFS. The accuracy, sensitivity, specificity, positive and negative predictive value of the apical IFS to predict cancer in the permanent section of the apical soft-tissue margin was 96%, 70%, 97%, 58%, and 98%, respectively. All the patients (n=15) with cancer at IFS had wide resections of additional tissue in the area of positive soft-tissue margin and all had no cancer in the additional resected tissue. Especially at the apex, IFS decreases the overall PSM status on surgical specimen by 5.1% (apical PSM from 8.6% to 3.5%).

CONCLUSION

Because of the low predictive value of IFS of bladder neck and neurovascular bundle/lateral pedicle their use is not recommended. IFS of the apex should be performed to reduce the PSM rate.

[Prognostic implications of positive margins in radical prostatectomy specimens]

To evaluate the histopathologic implication of positive margins of prostatectomy specimens in the biochemical recurrence.

MATERIAL AND METHODS

The study group consisted of 290 patients with clinically localized prostate cancer who were treated by radical retropubic prostatectomy. Patients with neoadjuvant hormonal therapy and positive lymph nodes were excluded. The mean age at the time of surgery was 63 years (range 47-73); 166 (57.2%) patients were T1c and 124 (42.8%) T2; the average time of folow-up was of 4 years (range 1-12). Positive surgical margins were defined as the presence of cancer cells at the surface inked of prostatectomy specimens. They were classified as: Margin for capsular incision (without extraprostatic extension evidence)/ margin for extraprostatic extension, margin with smooth rounded surface/margin with irregular surface, margin < or = 4 mm/margin > 4 mm, unifocal margin/multifocal margin. We define biochemical recurrence if the PSA exceeds 0.20 ng/ml in two consecutive determinations.

RESULTS

The overall rate of positive margins was 65/290 (22.4%). The 5-year survival free of biochemical recurrence was as follows: Negative margins 71% vs positive margins 44% (p < 0.001); positive margins for capsular incision 84% vs positive margins for extraprostatic extension 33% (p < 0.01); positive margins with smooth rounded surface 58% vs positive margins with irregular surface 26% (p < 0.01); positive margins < or = 4 mm 57% vs positive margins > 4 mm 32% (p < 0.05); unifocal margins 53% vs multifocal margins 0% (p < 0.01). The multivariate analysis revealed that preoperative PSA, Gleason score and pathological classification were the best predictors of biochemical recurrence.

CONCLUSIONS

Two groups are established of positive margin. The first group with high probability of biochemical recurrence: margin for extraprostatic. The second group with less probability of biochemical recurrence: margin for capsular incision, margin with smooth rounded surface, margin < or = 4 mm and unifocal margin.

Prediction of extraprostatic extension in the neurovascular bundle based on prostate needle biopsy pathology, serum prostate specific antigen and digital rectal examination

PURPOSE

There are few studies on predictors of extraprostatic extension (EPE) in the region of the neurovascular bundle (NVB). We investigated whether clinical information and prostate biopsy data could predict EPE of clinical localized prostate cancer.

MATERIALS AND METHODS

Through a retrospective analysis of the pathology database we identified 2,660 cases of clinically localized prostate cancer treated with radical retropubic prostatectomy without preoperative adjuvant therapy at The Johns Hopkins Hospital. The study sample involved a total of 3,006 lobes with prostate cancer including 2,070 with organ confined disease, 620 with EPE in the NVB at the posterolateral edge of the prostate and 316 with EPE in a region other than the NVB (EPE elsewhere). Through univariate and multivariate logistic regression analysis we determined whether patient age, year of surgery, serum prostate specific antigen, digital rectal examination, biopsy highest Gleason score, perineural invasion, percent of side specific biopsy cores with cancer, percent of each core involved with cancer and the maximum percent of a core involved with cancer was predictive of EPE in the NVB.

RESULTS

Prostate specific antigen (10 or greater vs less than 10), biopsy Gleason score (7 or greater vs 6 or less), digital rectal examination (abnormal vs normal), percent of side specific cores with tumor (greater than 33.3% vs 33.3% or less) and average percent involvement of each positive core (greater than 20% vs 20% or less) were all found to be statistically significant independent predictors of NVB penetration in multivariate analysis. The generated model stratifies each of these variables into high and low risk. The probability of EPE in the NVB was less than 10% in cases with 1 or fewer of the higher risk variables and was 10% or greater in cases with more than 1 of the higher risk variables.

CONCLUSIONS

The model generated in this study allows for the preoperative identification of patients with 10% or greater probability of EPE in the NVB. Our algorithm will help provide objective parameters that aid in the decision to spare the NVB safely.

Nerve-sparing radical retropubic prostatectomy: techniques and clinical considerations

There are essentially two ways to accomplish nerve preservation during radical retropubic prostatectomy: the 'apical approach' described by Walsh and the so-called 'lateral approach', a simplified method where the dissection is initially conducted on the portion of the bundles that courses posterolateral to the prostate. Do the different techniques differ in the ability to preserve potency and in the positive surgical margins rate? No previous study has addressed this question. Above all, the preoperative and intraoperative indications to spare or not the nerves remain a matter of debate. The present review is an attempt to elucidate these questions in light of the current literature.

Intraoperative Frozen Section Diagnosis in Urological Oncology

The intraoperative frozen sections are indicated if the pathological findings change the surgical procedure. In urological oncology is not recommended, as a general attitude, in the tumor diagnosis/staging during the surgery. The assessment of the surgical margins is recommended in partial surgical resections but the literature discourages its systematic use in the radical surgical resections. The assessment of the lymph nodes is specially indicated in the penile cancer with intermediate or high risk and non-palpable nodes, and is debated its utility in non-palpable lymph nodes of cystectomies and prostatectomies.

Intraoperative Frozen Section Analysis During Nerve Sparing Laparoscopic Radical Prostatectomy: Feasibility Study

PURPOSE

Nerve sparing radical prostatectomy may allow preservation of potency but it can increase positive surgical margins. We used intraoperative frozen section (IFS) analysis to monitor the nerve sparing procedure in laparoscopic prostatectomy.

MATERIALS AND METHODS

A total of 100 patients with localized prostatic carcinoma underwent bilateral intrafascial nerve sparing laparoscopic prostatectomy with IFS. A wedge of tissue was cut from base to apex in the region of the neurovascular bundles (NVBs) and analyzed on frozen section. If carcinoma was detected at the inked margin, the corresponding NVB was resected. Definitive margin status was evaluated after permanent section analysis of IFS prostatectomy specimens and eventually NVB specimens.

RESULTS

IFS analysis was positive in 24 patients, as confirmed in all by permanent section of the wedges. Three of these patients had positive margins in the prostate specimen at another site. Of the 76 tumors with negative IFSs 1 had positive margins on permanent sections of the wedges and 8 had positive margins on the prostate specimen at another site. IFS led to a decrease in the overall positive margin status from 33% to 12% and from 26.1% to 7.9% in pT2 tumors. Tumor was found on NVB resection in 8 cases (33%).

CONCLUSIONS

These results suggest that IFS analysis is a reliable method by which to monitor nerve sparing during laparoscopic prostatectomy. IFS could allow the surgeon to offer a nerve sparing procedure more frequently without compromising cancer control.