Detection of clinical unilateral T3a prostate cancer ? by digital rectal examination or transrectal ultrasonography?

Nerve-sparing radical prostatectomy using the neurovascular structure-adjacent frozen-section examination (NeuroSAFE): results after 20 years of experience

OBJECTIVES

To evaluate the long-term oncological outcomes and functional results of the neurovascular structure-adjacent frozen-section examination (NeuroSAFE) during nerve-sparing (NS) radical prostatectomy (RP).

MATERIALS AND METHODS

A 10-yr survival analysis on 11069 RPs performed with or without the NeuroSAFE, between January 2002 to June 2011 was carried out. In the NeuroSAFE cohort, the neurovascular structure-adjacent prostatic margins are removed and stained for cryo-sectioning during RP. In case of a PSM, partial or full removal of the neurovascular bundle was performed. The impact of NeuroSAFE on biochemical recurrence-free survival (BFS), salvage radiation therapy-free survival, metastasis-free survival, and prostate cancer-specific survival at 10 years was analyzed. 1-year (1-yr) erectile function (EF), 1-yr, and 2-yr continence rates were assessed in propensity score-based matched cohorts.

RESULTS

Median follow-up was 121 (IQR: 73, 156) months. No differences in BFS between NeuroSAFE and non-NeuroSAFE were recorded (10-yr BFS: NeuroSAFE vs non-Neurosafe, pT2: 81% vs 84%, p = 0.06; pT3a: 58% vs. 63%, p = 0.6; ≥pT3b: 22% vs. 27%, p = 0.99). No differences were found between the two groups in terms of sRFS (pT2: p = 0.1; pT3a: p = 0.4; ≥pT3b: p = 0.4) (Fig. 1B, Table 2), and MTS (pT2: p = 0.3; pT3a: p = 0.6; ≥pT3b: p = 0.9). The NeuroSAFE-navigated patients reported a better 1-yr EF than non-NeuroSAFE (68% vs. 58%, p = 0.02) and no differences in 1-yr and 2-yr continence rates (92.4% vs. 91.8%, and 93.4% vs. 93%, respectively). The main limitation is the retrospective study design.

CONCLUSIONS

While the NeuroSAFE approach did not show significant improvements in long-term oncologic or continence outcomes, it did provide an opportunity for a higher proportion of patients to improve postoperative functional results, possibly through increased nerve-sparing procedures.

Nomogram Predicting Locally Advanced Prostate Cancer in Patients with Clinically Organ-Confined Disease Who Underwent Robot-Assisted Radical Prostatectomy: A Retrospective Multicenter Cohort Study in Japan (The MSUG94 Group)

PURPOSE

We created a clinically applicable nomogram to predict locally advanced prostate cancer using preoperative parameters and performed external validation using an external independent validation cohort.

PATIENTS AND METHODS

From a retrospective multicenter cohort study of 3622 Japanese patients with prostate cancer who underwent robot-assisted radical prostatectomy at ten institutions, the patients were divided into two groups (MSUG cohort and validation cohort). Locally advanced prostate cancer was defined as pathological T stage ≥ 3a. A multivariable logistic regression model was used to identify factors strongly associated with locally advanced prostate cancer. Bootstrap area under the curve was calculated to assess the internal validity of the prediction model. A nomogram was created as a practical application of the prediction model, and a web application was released to predict the probability of locally advanced prostate cancer.

RESULTS

A total of 2530 and 427 patients in the MSUG and validation cohorts, respectively, met the criteria for this study. On multivariable analysis, initial prostate-specific antigen, prostate volume, number of cancer-positive and cancer-negative biopsy cores, biopsy grade group, and clinical T stage were independent predictors of locally advanced prostate cancer. The nomogram predicting locally advanced prostate cancer was demonstrated (area under the curve 0.72). Using a nomogram cutoff of 0.26, 464 of 1162 patients (39.9%) could be correctly diagnosed with pT3, and 2311 of 2524 patients (91.6%) could avoid underdiagnosis.

CONCLUSIONS

We developed a clinically applicable nomogram with external validation to predict the probability of locally advanced prostate cancer in patients undergoing robot-assisted radical prostatectomy.

NeuroSAFE PROOF: study protocol for a single-blinded, IDEAL stage 3, multi-centre, randomised controlled trial of NeuroSAFE robotic-assisted radical prostatectomy versus standard robotic-assisted radical prostatectomy in men with localized prostate cancer

BACKGROUND

Robotic radical prostatectomy (RARP) is a first-line curative treatment option for localized prostate cancer. Postoperative erectile dysfunction and urinary incontinence are common associated adverse side effects that can negatively impact patients' quality of life. Preserving the lateral neurovascular bundles (NS) during RARP improves functional outcomes. However, selecting men for NS may be difficult when there is concern about incurring in positive surgical margin (PSM) which in turn risks adverse oncological outcomes. The NeuroSAFE technique (intra-operative frozen section examination of the neurovascular structure adjacent prostate margin) can provide real-time pathological consult to promote optimal NS whilst avoiding PSM.

METHODS

NeuroSAFE PROOF is a single-blinded, multi-centre, randomised controlled trial (RCT) in which men are randomly allocated 1:1 to either NeuroSAFE RARP or standard RARP. Men electing for RARP as primary treatment, who are continent and have good baseline erectile function (EF), defined by International Index of Erectile Function (IIEF-5) score > 21, are eligible. NS in the intervention arm is guided by the NeuroSAFE technique. NS in the standard arm is based on standard of care, i.e. a pre-operative image-based planning meeting, patient-specific clinical information, and digital rectal examination. The primary outcome is assessment of EF at 12 months. The primary endpoint is the proportion of men who achieve IIEF-5 score ≥ 21. A sample size of 404 was calculated to give a power of 90% to detect a difference of 14% between groups based on a feasibility study. Oncological outcomes are continuously monitored by an independent Data Monitoring Committee. Key secondary outcomes include urinary continence at 3 months assessed by the international consultation on incontinence questionnaire, rate of biochemical recurrence, EF recovery at 24 months, and difference in quality of life.

DISCUSSION

NeuroSAFE PROOF is the first RCT of intra-operative frozen section during radical prostatectomy in the world. It is properly powered to evaluate a difference in the recovery of EF for men undergoing RARP assessed by patient-reported outcome measures. It will provide evidence to guide the use of the NeuroSAFE technique around the world.

TRIAL REGISTRATION

NCT03317990 (23 October 2017). Regional Ethics Committee; reference 17/LO/1978.

Multi-parametric MRI of the prostate: Factors predicting extracapsular extension at the time of radical prostatectomy

Objective

Extracapsular extension (ECE) of prostate cancer is a poor prognostic factor associated with progression, recurrence after treatment, and increased prostate cancer-related mortality. Accurate staging prior to radical prostatectomy is crucial in avoidance of positive margins and when planning nerve-sparing procedures. Multi-parametric magnetic resonance imaging (mpMRI) of the prostate has shown promise in this regard, but is hampered by poor sensitivity. We sought to identify additional clinical variables associated with pathologic ECE and determine our institutional accuracy in the detection of ECE amongst patients who went on to radical prostatectomy.

Methods

mpMRI studies performed between the years 2012 and 2014 were cross-referenced with radical prostatectomy specimens. Predictive properties of ECE as well as additional clinical and biochemical variables to identify pathology-proven prostate cancer ECE were analyzed.

Results

The prevalence of ECE was 32.4%, and the overall accuracy of mpMRI for ECE was 84.1%. Overall mpMRI sensitivity, specificity, positive predictive value, and negative predictive value for detection of ECE were 58.3%, 97.8%, 93.3%, and 81.5%, respectively. Specific mpMRI characteristics predictive of pathologic ECE included primary lesion size ((20.73 ± 9.09) mm, mean ± SD, p < 0.001), T2 PIRADS score (p = 0.009), overall primary lesion score (p < 0.001), overall study suspicion score (p = 0.003), and MRI evidence of seminal vesicle invasion (SVI) (p = 0.001).

Conclusion

While mpMRI is an accurate preoperative assessment tool for the detection of ECE, its overall sensitivity is poor, likely related to the low detection rate of standard protocol MRI for microscopic extraprostatic disease. The additional mpMRI findings described may also be considered in surgical margin planning prior to radical prostatectomy.

When to biopsy seminal vesicles

OBJECTIVES

The involvement of seminal vesicles in prostate cancer can affect the prognosis and determine the treatment. The objective of this study was to determine whether we could predict its infiltration at the time of the prostate biopsy to know when to indicate the biopsy of the seminal vesicles.

MATERIAL AND METHODS

observational retrospective study of 466 patients who underwent seminal vesicle biopsy. The indication for this biopsy was a prostate-specific antigen (PSA) level greater than 10 ng/ml or an asymmetric or obliterated prostatoseminal angle. The following variables were included in the analysis: PSA level, PSA density, prostate volume, number of cores biopsied, suspicious rectal examination, and preservation of the prostatoseminal angle, studying its relationship with the involvement of the seminal vesicles.

RESULTS

Forty-one patients (8.8%) had infiltrated seminal vesicles and 425 (91.2%) had no involvement. In the univariate analysis, the cases with infiltration had a higher mean PSA level (P < .01) and PSA density (P < .01), as well as a lower mean prostate volume (P < .01). A suspicious rectal examination (20.7% of the infiltrated vesicles) and the obliteration or asymmetry of the prostatoseminal angle (33.3% of the infiltrated vesicles) were significantly related to the involvement (P < .01). In the multivariate analysis, we concluded that the probability of having infiltrated seminal vesicles is 5.19 times higher if the prostatoseminal angle is not preserved (P < .01), 4.65 times higher for PSA levels >19.60 ng/dL (P < .01) and 2.95 times higher if there is a suspicious rectal examination (P = .014). Furthermore, this probability increases by 1.04 times for each unit of prostate volume lower (P < .01). The ROC curves showed maximum sensitivity and specificity at 19.6 ng/mL for PSA and 0.39 for PSA density.

CONCLUSIONS

In this series, greater involvement of seminal vesicles was associated with a PSA level ≥20 ng/ml, a suspicious rectal examination and a lack of prostatoseminal angle preservation.

Identification and validation of potential new biomarkers for prostate cancer diagnosis and prognosis using 2D-DIGE and MS

This study was designed to identify and validate potential new biomarkers for prostate cancer and to distinguish patients with and without biochemical relapse. Prostate tissue samples analyzed by 2D-DIGE (two-dimensional difference in gel electrophoresis) and mass spectrometry (MS) revealed downregulation of secernin-1 (P < 0.044) in prostate cancer, while vinculin showed significant upregulation (P < 0.001). Secernin-1 overexpression in prostate tissue was validated using Western blot and immunohistochemistry while vinculin expression was validated using immunohistochemistry. These findings indicate that secernin-1 and vinculin are potential new tissue biomarkers for prostate cancer diagnosis and prognosis, respectively. For validation, protein levels in urine were also examined by Western blot analysis. Urinary vinculin levels in prostate cancer patients were significantly higher than in urine from nontumor patients (P = 0.006). Using multiple reaction monitoring-MS (MRM-MS) analysis, prostatic acid phosphatase (PAP) showed significant higher levels in the urine of prostate cancer patients compared to controls (P = 0.012), while galectin-3 showed significant lower levels in the urine of prostate cancer patients with biochemical relapse, compared to those without relapse (P = 0.017). Three proteins were successfully differentiated between patients with and without prostate cancer and patients with and without relapse by using MRM. Thus, this technique shows promise for implementation as a noninvasive clinical diagnostic technique.

The accuracy of magnetic resonance imaging in radical prostatectomy

AIMS

The aim of this study was to examine the accuracy of standard magnetic resonance imaging (MRI) in the localised staging of prostate cancer in those who had undergone radical prostatectomy.

PATIENTS AND METHODS

The cohort consisted of 110 patients who had undergone MRI for staging of prostate cancer and subsequently underwent radical prostatectomy. T stage was analysed both on MRI and from the specimen following radical surgery.

RESULTS

Of the patients 57% of patients had their disease up-staged following radical surgery from preoperative MRI findings. Of those patients who had their disease up-staged following surgery, nearly 50% of patients had gone from organ confined disease at time of MRI to extra-prostatic involvement from the surgical specimen.

CONCLUSION

We have reported that MRI has a wide range of accuracy. Given developments in MRI technologies further work should be pursued to help in the staging of this disease for which decision to treat is difficult.

[Value of MRI in detection of extracapsular extension in prostate cancer: a prospective study comparing imaging and histology]

OBJECTIVE

To establish MRI's performances for the detection of extracapsular progression of prostate carcinoma, in a single center, analyzing the correlation between MRI imaging and histological analysis of prostate specimen.

METHODS

From February 2008 to June 2012, all the patients selected for prostatectomy had a pre-operative MRI. Diffusion, T2 and dynamic T1 with gadolinium injection sequences were realized on a 1.5T-MRI with external antenna. All imaging data was analyzed by a specialized radiologist. Prostate specimens were histologically analyzed throughout large blades for utmost topographic comparison. The histological TNM was compared to the MRI data. MRI's capacity in determining the existence and the size of extracapsular progression was studied.

RESULTS

One hundred and fifty-eight patients (median age 62 years old, mean PSA 8.6 ng/mL) were included, among which 45% of d'Amico low risk and 55% of intermediate and high risk. Histological results were 63% of pT2 and 37% of pT3. MRI's sensibility and specificity for detecting extracapsular progression were 0.30 and 0.85 respectively (PPV 0.54; NPV 0.67), with a 65% accuracy. In the low risk group, sensibility equaled to 0.16.

CONCLUSION

In our experience, MRI results were not reliable to influence the choice of treatment. It should be executed by expert radiologists, who are still very few.

Efficacy of using three-tesla magnetic resonance imaging diagnosis of capsule invasion for decision-making about neurovascular bundle preservation in robotic-assisted radical prostatectomy

Purpose

To evaluate the efficacy of using 3-tesla (T) magnetic resonance imaging (MRI) diagnosis of extracapsular extension (ECE) for decision-making about neurovascular bundle (NVB) preservation in robot-assisted radical prostatectomy (RARP) for prostate cancer (PC).

Materials and Methods

We prospectively collected data on PC patients (n=67) who underwent preoperative 3-T MRI before RARP. The choice between nerve sparing or resection was based on 3-T MRI findings of ECE. We compared the MRI findings with the pathological data on surgical margins. Our clinical staging in this study was defined only by MRI.

Results

When the data were divided by prostate lobe (right lobe or left lobe, n=134), 3-T MRI showed 28 positive cases of ECE in 134 prostate lobes, allowing NVB preservation in 42 cases (31.3%). Nerve-sparing surgery was achieved in 38.7% of cases in which clinical T2 staging by MRI was reported. The pathological data revealed that 10 of 134 prostate lobes had positive ECE. The overall sensitivity, specificity, positive predictive value, and negative predictive value for predicting stage T3 (positive ECE) by side were 60.0% (12 of 20 sides), 86.0% (98 of 114 sides), 42.9% (12 of 28 sides), and 92.5% (98 of 106 sides), respectively.

Conclusions

Three-T MRI prior to RARP enables the use of ECE diagnosis to guide decision-making about NVB preservation, with comparatively high specificity and negative predictive value. Further prospective studies are underway to reach more definitive conclusions.

Accuracy of high resolution (1.5 tesla) pelvic phased array magnetic resonance imaging (MRI) in staging prostate cancer in candidates for radical prostatectomy: results from a prospective study

OBJECTIVE

To evaluate the role of pelvic phased array MRI in staging prostate cancer (CaP).

MATERIALS AND METHODS

We prospectively collected data over 12 months on CaP patients who underwent preoperative MR imaging with a pelvic phased array before radical prostatectomy. MR images were analyzed prospectively by 2 radiologists. MR imaging findings were then correlated with pathologic findings.

RESULTS

Overall, 101 patients were included with a mean PSA level of 8 (range 1.8-30). Reader 1 (AUC 0.895, 95% CI 0.791-0.999) had a higher performance than reader 2 (AUC 0.687, 95% CI, 0.555-0.819) and than DRE (AUC 0.728, 95% CI, 0.599-0.857) in discriminating T2 from T3 CaP (P = 0.01). The κ-index of inter-observer agreement was 0.56. A model that combines MRI findings, DRE, PSA, and Gleason score was the most competitive for staging (AUC 0.895, 95% CI, 0.791-0.999). For the multivariate analysis, 3 criteria were significantly associated with extracapsular extension: asymmetry of the neuro-vascular bundles (P = 0.001), asymmetric enhancement of neurovascular bundles (P = 0.02), and bulging of the capsule (P = 0.0003).

CONCLUSION

Pelvic phased array MRI presented satisfying results in its ability to adequately stage CaP and notably in detecting the extracapsular extension of tumors. It is likely to provide reliable information but rather in the hands of an experienced radiologist.

Predictors in the outcome of 125I brachytherapy as monotherapy for prostate cancer

A number of different prostate cancer treatment modalities exist. Nomograms are used to assist clinicians and patients in choosing the most appropriate treatment. However, the predicted outcome for (125)I brachytherapy is much worse than what would be expected considering the actual survival rates. This underestimation may result in suboptimal treatment decisions. Therefore, better predictors for outcome after (125)I brachytherapy are necessary. The following factors, which may either influence outcome or predict outcome after brachytherapy, are discussed: tumor characteristics and risk stratification, patient age at treatment, obesity, adjuvant androgen-deprivation therapy, prostate-specific antigen bounce, implantation technique and dosimetry. For the prediction of outcome after (125)I brachytherapy, as long as the quality of the implant is optimal, only high-risk prostate cancer was found to have a negative impact on outcome.

[Oncologic and functional outcomes after radical prostatectomy in T3 prostate cancer]

According to current literature, the gold standard treatment for T3 prostate cancer is the combination of radiotherapy and extended hormonotherapy. Clinical staging based on digital rectal examination seems useless nowadays, since 20% of T3 prostate cancer is overevaluated during physical examination. Prostatic MRI is extensively needed to evaluate extraprostatic extension during preoperative work-up. EAU guidelines recommend radical prostatecomy only in selected patients: less than or equal to cT3a, PSA less than 20 ng/ml and biopsy Gleason score less than or equal to 8. Carcinologic control obtained after radical prostatectomy is variable from one series to another, with biochemical free survival rate at 5, 10 and 15 years that range from 45 to 62%, 43 to 51%, and 38 to 49%. Specific survival rates at 5, 10 and 15 years are, respectively, of 84 to 98%, 85 to 91% and 76 to 84%. Surgical margins rate differ from 22 up to 61% corresponding to several operative techniques and surgeon's own experience. Regarding urinary continence, functional outcomes are in line with those of prostatectomy for localized prostate cancer. Considering erectile dysfunction, rates are linked with the type of surgery, which can be extensive or not. There is no impact on overall or specific survival of neoadjuvant treatments. One current question remains the efficacy of early adjuvant treatment after prostatectomy, especially adjuvant irradiation. Radical prostatectomy can be considered in selected cases as a viable alternative first-line treatment option. However, patients have to be warned that they may undergo complementary treatments during the postoperative course of the disease.

Transrectal ultrasound in the staging of clinical T3a prostate cancer

INTRODUCTION

The clinical staging of T3a prostate cancer is usually based on digital rectal examination (DRE). Overstaging of clinical T3a prostate cancer is present in 13-27% of the cases presented and understaging is in the range of 30%. The value of transrectal ultrasound (TRUS) as a staging tool is not generally accepted. The purpose of this study is to determine whether TRUS can refine the local staging in unilateral clinical T3a (cT3a) prostate cancer.

PATIENTS AND METHODS

Between 1987 and 2004, 200 patients were staged as unilateral cT3a prostate cancer by DRE. All patients underwent radical prostatectomy and bilateral pelvic lymphadenectomy. Preoperative TRUS staging was performed for all patients. Final histopathological staging was compared with DRE and TRUS staging. The operable group (OG) was defined as T2 to unilateral T3a, and the advanced group (AG) was defined as bilateral T3a to T4.

RESULTS

All DRE patients were assumed operable. However, in this group histopathology showed 27.0% of the patients had advanced disease. TRUS confirmed 184 patients to be operable (140 having unilateral cT3a, 44 patients having cT1c to cT2). Sixteen patients were considered to have advanced disease by TRUS. Importantly, in this group, 68.7% of the cases were indeed confirmed to have advanced disease by histopathology.

CONCLUSION

TRUS can be used to refine clinical staging in unilateral cT3a prostate cancer. In cases where TRUS indicates advanced disease, it might be wise to trust the TRUS staging, rather than the DRE.