Comparison of semi-extended and standard lymph node dissection in radical prostatectomy: A single-institute experience

Utility of Lymphadenectomy in Prostate Cancer: Where Do We Stand?

The purpose of this review is to summarize the current knowledge on lymph node dissection (LND) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP). Despite a growing body of evidence, the utility and therapeutic and prognostic value of such an approach, as well as the optimal extent of LND, remain unsolved issues. Although LND is the most accurate staging procedure, the direct therapeutic effect is still not evident from the current literature, which limits the possibility of establishing clear recommendations. This indicates the need for further robust and adequately designed high-quality clinical trials.

Impact of Pelvic Lymph Node Dissection and Its Extent on Perioperative Morbidity in Patients Undergoing Radical Prostatectomy for Prostate Cancer: A Comprehensive Systematic Review and Meta-analysis

CONTEXT

Pelvic lymph node dissection (PLND) yields the most accurate staging in patients undergoing radical prostatectomy (RP) for prostate cancer (PCa), although it can be associated with morbidity.

OBJECTIVE

To systematically evaluate the impact of PLND extent on perioperative morbidity in patients undergoing RP. A new PLND-related complication assessment tool is proposed.

EVIDENCE ACQUISITION

A systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) was conducted. MEDLINE/PubMed, Scopus, Embase and Web of Science databases were searched to yield studies discussing perioperative complications following RP and PLND. The extent of PLND was classified according to the European Association of Urology PCa guidelines. Studies were categorized according to the extent of PLND. Intra- and postoperative complications were classified as "strongly," "likely," or "unlikely" related to PLND. Anatomical site of perioperative complications was recorded. A cumulative meta-analysis of comparative studies was conducted using Review Manager 5.3 (Cochrane Collaboration, Oxford, UK).

EVIDENCE SYNTHESIS

Our search generated 3645 papers, with 176 studies meeting the inclusion criteria. Details of 77 303 patients were analyzed. Of these studies, 84 (47.7%), combining data on 28 428 patients, described intraoperative complications as an outcome of interest. Overall, 534 (1.8%) patients reported one or more intraoperative complications. Postoperative complications were reported in 151 (85.7%) studies, combining data on 73 629 patients. Overall, 10 401 (14.1%) patients reported one or more postoperative complication. The most reported postoperative complication strongly related to PLND was lymphocele (90.6%). The pooled meta-analysis revealed that RP + limited PLND/standard PLND had a significantly decreased risk of experiencing any intraoperative complication (risk ratio [RR]: 0.55; p =  0.01) and postoperative complication strongly related to PLND (RR: 0.46; p =  <0.00001), particularly for lymphocele formation (RR: 0.52; p =  0.0003) and thromboembolic events (RR: 0.59; p =  0.008), when compared with extended/superextended PLND. The extent of PLND was confirmed to be an independent predictor of lymphocele formation (RR: 1.77; p <  0.00001).

CONCLUSIONS

The perioperative morbidity of PLND in patients undergoing RP and PLND for PCa significantly correlates with the extent of PLND. More standardized reporting of intra- and postoperative complications is needed to better estimate the direct impact of PLND extent on perioperative morbidity.

PATIENT SUMMARY

Pelvic lymph node dissection (PLND) is the most accurate method for staging in patients undergoing radical prostatectomy for prostate cancer, although it can be associated with complications. This study aims to systematically evaluate the impact of PLND extent on perioperative complications in these patients. We found that intra- and postoperative complications correlate significantly with the extent of PLND. A more rigorous assessment and thorough reporting of perioperative complications are recommended.

Head-to-Head Comparison of Two Nomograms Predicting Probability of Lymph Node Invasion in Prostate Cancer and the Therapeutic Impact of Higher Nomogram Threshold

Introduction: The aim of the study was to compare the performance of the 2012 Briganti and Memorial Sloan Kettering Cancer Center (MSKCC) nomograms as a predictor for pelvic lymph node invasion (LNI) in men who underwent radical prostatectomy (RP) with pelvic lymph node dissection (PLND), to examine their performance and to analyse the therapeutic impact of using 7% nomogram cut-off. Materials and Methods: The study cohort consisted of 807 men with clinically localised prostate cancer (PCa) who underwent open RP with PLND between 2001 and 2019. The area under the curve (AUC) of the receiver operator characteristic analysis was used to quantify the accuracy of the 2012 Briganti and MSKCC nomograms to predict LNI. Calibration plots were used to visualise over or underestimation by the models and a decision curve analysis (DCA) was performed to evaluate the net benefit associated with the used nomograms. Results: A total of 97 of 807 patients had LNI (12%). The AUC of 2012 Briganti and MSKCC nomogram was 80.6 and 79.2, respectively. For the Briganti nomogram using the cut-off value of 7% would lead to reduce PLND in 47% (379/807), while missing 3.96% (15/379) cases with LNI. For the MSKCC nomogram using the cut-off value of 7% a PLND would be omitted in 44.5% (359/807), while missing 3.62% (13/359) of cases with LNI. Conclusions: Both analysed nomograms demonstrated high accuracy for prediction of LNI. Using a 7% nomogram cut-off would allow the avoidance up to 47% of PLNDs, while missing less than 4% of patients with LNI.

Establishment and validation of a novel predictive model to quantify the risk of bone metastasis in patients with prostate cancer

Background

Patients with prostate cancer (PCa) commonly suffer from bone metastasis during disease progression. This study aims to construct and validate a nomogram to quantify bone metastasis risk in patients with PCa.

Methods

Clinicopathological data of patients diagnosed with PCa between 2010 and 2015 were retrospectively retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Predictors for bone metastasis were identified by logistic regression analyses to establish a nomogram. The concordance index (c-index) and calibration plots were generated to assess the nomogram’s discrimination, and the area under the receiver operating characteristic curve (AUC) was used to compare the precision of the nomogram with routine staging systems. The nomogram’s clinical performance was evaluated by decision curve analysis (DCA) and clinical impact curves (CIC). Independent prognostic factors were identified by Cox regression analysis.

Results

A total of 168,414 eligible cases were randomly assigned to the training cohort or validation cohort at a ratio of 1:1. The nomogram, which was established based on independent factors, showed good accuracy, with c-indexes of 0.911 in the training set and 0.910 in the validation set. Calibration plots also approached 45 degrees. After other distant metastatic sites were included in the predictive model, the new nomogram displayed superior prediction performance. The AUCs and net benefit of the nomograms were both higher than those of other routine staging systems. Furthermore, bone metastasis prediction points were shown to be a new risk factor for overall survival.

Conclusions

Novel validated nomograms can effectively predict the risk of bone metastasis in patients with PCa and help clinicians improve cancer management.

THE ROLE OF LYMPHADENECTOMY IN PROSTATE CANCER PATIENTS

Prostate cancer is one of the most important men's health issues in developed countries. For patients with prostate cancer a preoperative staging of the disease must be made. Involvement of lymph nodes could be assessed using imaging methods (CT or/and MRI), however, newer methods also exist (PET/CT, PSMA PET/CT). For some patients during radical prostatectomy a pelvic lymphadenectomy is recommended. Pelvic lymphadenectomy is indicated in intermediate- and high-risk group patients and with increased probability of lymph node invasion. The most used prediction tools for preoperative assessment of lymph nodes are Briganti and MSKCC nomograms and Partin tables. Pelvic lymphadenectomy can include different lymph nodes group, but extended lymphadenectomy is the recommended procedure. In 1-20% of patients, the lymph node invasion is present. Pelvic lymphadenectomy is primarily a diagnostic and staging method, and in minority of patients with positive lymph nodes it can be a curative method, too. In other patients with positive lymph nodes adjuvant therapy (radiotherapy and androgen deprivation therapy) can be beneficial.

Robot-assisted extended lymphadenectomy in prostate cancer

INTRODUCTION

The extent of lymph node dissection (LND) and its potential survival benefit are still a matter of debate. Aim of our review was to summarize the latest literature data regarding the surgical templates, the potential oncological benefits, the functional outcomes and the complications of extended lymph node dissection (eLND) during robot-assisted radical prostatectomy (RARP).

EVIDENCE ACQUISITION

We systematically reviewed all relevant studies using PubMed, MEDLINE, Embase, American Urological Association (AUA), European Society of Medical Oncology (ESMO) and European Association of Urology (EAU) guidelines.

EVIDENCE SYNTHESIS

A narrative synthesis of all relevant publications on surgical templates, complications, oncological and functional outcomes of robot assisted eLND was undertaken.

CONCLUSIONS

A great deal of evidence supports that an extended template of LND is not only technically feasible but also safe in the context of RARP. It is really promising that in the era of minimally invasive surgery, parameters like the lymph node yield and the detection rates of positive lymph nodes during LND have become highly comparable with open series. The extended approach has already proved its benefits in terms of proper patient staging but more studies are needed with regard to functional outcomes and oncological benefits of this procedure.

Therapeutic Value of Standard Versus Extended Pelvic Lymph Node Dissection During Radical Prostatectomy for High-Risk Prostate Cancer

Extent of pelvic lymph node dissection (PLND) during radical prostatectomy (RP) remains a subject of debate. Here, we review the literature covering the value of extended PLND (ePLND) during RP for high-risk prostate cancer (PCa) over a standard PLND, with a focus on potential therapeutic advantage. PLND may provide valuable prognostic information to high-risk PCa patients, and incorporating the common iliac and presacral nodes to ePLND templates further improves pathologic nodal staging accuracy. Although increased PLND extent is associated with increased lymphocele/lymphedema rates, it is not associated with increased venous thromboembolism rates. The therapeutic role of ePLND remains uncertain. While recent retrospective studies suggest an increased number of nodes removed within the ePLND template are associated with improved survival outcomes, such retrospective studies cannot completely adjust for the Will Rodgers phenomenon or surgeon-specific factors. Thus, the results of randomized trials are eagerly awaited in this arena.

The Benefits and Harms of Different Extents of Lymph Node Dissection During Radical Prostatectomy for Prostate Cancer: A Systematic Review

CONTEXT

There is controversy regarding the therapeutic role of pelvic lymph node dissection (PLND) in patients undergoing radical prostatectomy for prostate cancer (PCa).

OBJECTIVE

To systematically review the relevant literature assessing the relative benefits and harms of PLND for oncological and non-oncological outcomes in patients undergoing radical prostatectomy for PCa.

EVIDENCE ACQUISITION

MEDLINE, MEDLINE In-Process, Embase, and the Cochrane Central Register of Controlled Trials were searched up to December 2015. Comparative studies evaluating no PLND, limited, standard, and (super)-extended PLND that reported oncological and non-oncological outcomes were included. Risk-of-bias and confounding assessments were performed. A narrative synthesis was undertaken.

EVIDENCE SYNTHESIS

Overall, 66 studies recruiting a total of 275,269 patients were included (44 full-text articles and 22 conference abstracts). Oncological outcomes were addressed by 29 studies, one of which was a randomized clinical trial (RCT). Non-oncological outcomes were addressed by 43 studies, three of which were RCTs. There were high risks of bias and confounding in most studies. Conflicting results emerged when comparing biochemical and clinical recurrence, while no significant differences were observed among groups for survival. Conversely, the majority of studies showed that the more extensive the PLND, the greater the adverse outcomes in terms of operating time, blood loss, length of stay, and postoperative complications. No significant differences were observed in terms of urinary continence and erectile function recovery.

CONCLUSIONS

Although representing the most accurate staging procedure, PLND and its extension are associated with worse intraoperative and perioperative outcomes, whereas a direct therapeutic effect is still not evident from the current literature. The current poor quality of evidence indicates the need for robust and adequately powered clinical trials.

PATIENT SUMMARY

Based on a comprehensive review of the literature, this article summarizes the benefits and harms of removing lymph nodes during surgery to remove the prostate because of PCa. Although the quality of the data from the studies was poor, the review suggests that lymph node removal may not have any direct benefit on cancer outcomes and may instead result in more complications. Nevertheless, the procedure remains justified because it enables accurate assessment of cancer spread.