Surgical Strategies for Lymphocele Prevention in Minimally Invasive Radical Prostatectomy and Lymph Node Dissection: A Systematic Review

The Association of a Peritoneal Interposition Flap With Lymphocele Formation After Pelvic Lymph Node Dissection During Robotic-assisted Laparoscopic Radical Prostatectomy: A Systematic Review and Meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis to evaluate the association of a peritoneal interposition flap (PIF) with lymphocele formation following robotic-assisted laparoscopic radical prostatectomy (RALP) with pelvic lymph node dissection.

METHODS

We conducted a systematic search of MEDLINE, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials through August 30, 2023, to identify randomized and nonrandomized studies comparing RALP with pelvic lymph node dissection with and without PIF. A random effects meta-analysis was then performed to evaluate the associations of PIF with 90-day postoperative outcomes.

RESULTS

Five randomized controlled trials (RCTs) and four observational studies, including a total of 2941 patients, were included. The use of PIF was associated with a reduced risk of 90-day symptomatic lymphocele formation after RALP when examining only RCTs (pooled odds ratios [OR] 0.44, 95% CI 0.28-0.69; I2 =3%) and both RCTs and observational studies (OR 0.35, 95% CI 0.22-0.56; I2 =17%). Similarly, use of PIF was associated with a reduced risk of 90-day any lymphocele formation (OR 0.40, 95% CI 0.28-0.56, I2 =39%). There were no statistically significant differences in postoperative complications between the two groups (OR 0.89; 95% CI 0.69-1.14; I2 =20%).

CONCLUSION

Use of the PIF is associated with an approximately 50% reduced risk of symptomatic and any lymphocele formation within 90-days of surgery, and it is not associated with an increase in postoperative complications.

The role and controversy of pelvic lymph node dissection in prostate cancer treatment: a focused review

Pelvic lymph node dissection (PLND) is commonly performed alongside radical prostatectomy. Its primary objective is to determine the lymphatic staging of prostate tumors by removing lymph nodes involved in lymphatic drainage. This aids in guiding subsequent treatment and removing metastatic foci, potentially offering significant therapeutic benefits. Despite varying recommendations from clinical practice guidelines across countries, the actual implementation of PLND is inconsistent, partly due to debates over its therapeutic value. While high-quality evidence supporting the superiority of PLND in oncological outcomes is lacking, its role in increasing surgical time and risk of complications is well-recognized. Despite these concerns, PLND remains the gold standard for lymph node staging in prostate cancer, providing invaluable staging information unattainable by other techniques. This article reviews PLND's scope, guideline perspectives, implementation status, oncologic and non-oncologic outcomes, alternatives, and future research needs.

Impact of peritoneal reconfiguration on lymphocele formation after robot-assisted radical prostatectomy with pelvic lymph node dissection: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Different strategies have been proposed to prevent lymphocele (LC) formation after radical prostatectomy (RARP) with pelvic lymph node dissection (PLND). According to several recently published randomized control trials (RCTs) on the topic, peritoneal reconfiguration appears to be associated with promising results. This systematic review aimed to assess the impact of peritoneal reconfiguration on LC formation in patients undergoing RARP and PLND.

METHODS

A comprehensive bibliographic search was conducted in August 2023. Studies assessing patients with prostate cancer undergoing RARP with PLND (P) and concomitant peritoneal reconfiguration (I) compared or not with other techniques (C) to prevent LC formation (O) were included. Original prospective and retrospective studies (S) were selected. LC and symptomatic LC rates were chosen as co-primary outcomes. Only RCTs were included in the meta-analysis.

RESULTS

Eleven studies investigating 2991 patients were included in the systematic review, and five RCTs evaluating 1712 subjects were deemed eligible for meta-analysis. Peritoneal flap (PF) was the most common surgical technique used for LC prevention (9 studies). A significantly lower likelihood of LC was observed after PF (OR 0.82, 95% CI 0.27-1.37, I2 = 74.54%), with no significant difference in terms of symptomatic LC (OR 0.21, 95% CI -0.41-0.84, I2 = 0%). Probability of LC-related complications (OR 0.36, 95% CI 0.04-0.67, I2 = 0%), Clavien-Dindo ≥ 3 overall complications (OR 0.61, 95% CI 0.21-1.0, I2 = 0%), and Clavien-Dindo ≥ 3 LC-related complications (OR 0.98, 95% CI 0.29-1.67, I2 = 0%) were significantly lower after PF.

CONCLUSIONS

PF after RARP with PLND reduces LC formation, LC-related complications, and severe postoperative adverse events.

Effect of Peritoneal Interposition Flap to Prevent Symptomatic Lymphoceles in Robot-Assisted Radical Prostatectomy with Pelvic Lymphadenectomy: A Meta-Analysis and Systematic Review

Background: This systematic review and meta-analysis investigated whether peritoneal interposition flap (PIF) prevent lymphocele formation after robot-assisted radical prostatectomy with extended pelvic lymph node dissection. Materials and Methods: We performed a systematic review and cumulative meta-analysis of the primary outcomes according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, Assessing the Methodological Quality of Systematic Reviews guidelines and risk-of-bias tool. Five databases, including Medline, PubMed, Cochrane Library, Scopus, and Web of Science, were systematically searched. The time frame of the search was set from the creation of the database to February 2023. Results: Meta-analysis of symptomatic lymphoceles (sLCs) rates revealed significant difference between PIF and no PIF group (eight studies pooled; p = 0.005), The sLCs rates account for 2.6% (28/1074) and 7.1% (85/1186) in the PIF and no PIF group, respectively. The resulting odds ratio was 0.34 (95% confidence interval: 0.16-0.73), taking into account the heterogeneity of these studies (Q = 14.32, p = 0.05; I2 = 51%). Conclusion: PIF is an effective intraoperative modification on the prevention or reduction of sLC, which is worthy of further clinical promotion. Systematic Review Registration: National Institute for Health and Care Research, identifier CRD42022364461.

High BMI and Surgical Time Are Significant Predictors of Lymphocele after Robot-Assisted Radical Prostatectomy

Lymphoceles (LC) occur in up to 60% after robot-assisted radical prostatectomy (RARP) and pelvic lymphadenectomy (PLND). In 2-10%, they are symptomatic and may cause complications and require treatment. Data on risk factors for the formation of lymphoceles after RARP and PNLD remain sparse in the urologic literature and are inconclusive to date. The underlying data of this secondary analysis were obtained from the prospective multi-center RCT ProLy. We performed a multivariate analysis to focus on the potential risk factors that may influence lymphocele formation. Patients with LC had a statistically significant higher BMI (27.8 vs. 26.3 kg/m², p < 0.001; BMI ≥ 30 kg/m²: 31 vs. 17%, p = 0.002) and their surgical time was longer (180 vs. 160 min, p = 0.001) In multivariate analysis, the study group (control vs. peritoneal flap, p = 0.003), BMI (metric, p = 0.028), and surgical time (continuous, p = 0.007) were independent predictors. Patients with symptomatic lymphocele presented with higher BMI (29 vs. 26.6 kg/m², p = 0.007; BMI ≥ 30 kg/m²: 39 vs. 20%, p = 0.023) and experienced higher intraoperative blood loss (200 vs. 150 mL, p = 0.032). In multivariate analysis, BMI ≥ 30 kg/m² vs. < 30 kg/m² was an independent predictor for the formation of a symptomatic lymphocele (p = 0.02). High BMI and prolonged surgical time are general risk factors for the development of LC. Patients with a BMI ≥ 30 kg/m² had a higher risk for symptomatic lymphoceles.

A Peritoneal Purse-String Suture Prevents Symptomatic Lymphoceles in Retzius-Sparing Robot-Assisted Radical Prostatectomy

BACKGROUND

The retzius-sparing approach for robotic-assisted radical prostatectomy (RARP) has been increasingly adopted. Symptomatic lymphoceles are a widespread complication of RARP with pelvic lymph node dissection. Here, we present a new technique, the peritoneal purse-string suture (PPSS), that seems to reduce the rate of symptomatic lymphoceles following retzius-sparing RARP with extended pelvic lymph node dissection (ePLND).

METHODS

The radical prostatectomy and bilateral lymphadenectomy are performed through three separate peritoneal openings. The PPSS uses a single suture in a way similar to a purse-string suture; the openings of both lymphadenectomy fields are widened, and the rectovesical opening from the prostatectomy is simultaneously closed. This report retrospectively evaluates the perioperative and postoperative outcomes of two consecutive patient cohorts undergoing RARP with ePLND by a single surgeon between May 2015 and June 2019, one cohort prior to introducing PPSS as control (n = 145) and the other after introducing PPSS (n = 91).

RESULTS

The two study groups were comparable on baseline characteristics, except ASA. There were no Clavien-Dindo grade IV-V complications, and comparable rates of grade I-III complications. The difference in postoperative lymphocele formation was 22% in PPSS versus 27% in the control group (p = 0.33). The rate of symptomatic lymphoceles was significantly lower in the PPSS group (3% vs. 10%, p = 0.047).

CONCLUSION

The PPSS is a feasible procedure that reduces symptomatic lymphoceles in patients undergoing RARP with a retzius-sparing approach.

Robot-Assisted Treatment of Symptomatic Lymphocele Postradical Prostatectomy and Lymphadenectomy in the Era or Robotic Surgery: Narrative Review

Background: Pelvic lymphnode dissection (PLND) is an integral part of surgical treatment for localized intermediate and high-risk prostate cancer. The most common complication of PLND is lymphocele formation. In the majority of cases the development of lymphoceles is clinically asymptomatic but in case of symptomatic/infected lymphocele an active treatment is required. The aim of this article is to analyse the current evidence on the treatment of symptomatic/infected lymphocele trough robotic approach. Materials and Methods: The search was applied to PubMed, EMBASE, and Cochrane databases with following terms: "lymphocele", "symptomatic", "infected", "robot-assisted AND radical prostatectomy", "robot-assisted", "treatment". Results: The search identified three series focusing on the treatment by robot-assisted approach of symptomatic and/or infected lymphocele. The main and most frequent reason for performing the robotic treatment was an infected lymphocele, the median time from robot-assisted radical prostatectomy and PLND to robotic treatment of lymphocele was 118 days (range 30-240). Robot-assisted treatment was successful in all reports. Conclusions: The drainage of lymphocele with the robot-assisted approach appeared safe, feasible, and with satisfactory outcomes for the definitive treatment of symptomatic/infected lymphocele.

Pelvic Lymph Node Dissection at Radical Prostatectomy for Intermediate Risk Prostate Cancer: Assessing Utility and Nodal Metastases Within a Statewide Quality Improvement Consortium

OBJECTIVE

To assess which patients with intermediate-risk PCa would benefit from a pelvic lymph node dissection (PLND) across the Michigan Urological Surgery Improvement Collaborative, given the discrepancy in recommendations. AUA guidelines for localized prostate cancer (PCa) state that PLND is indicated for patients with unfavorable intermediate-risk and high-risk PCa and can be considered in favorable intermediate-risk patients. NCCN guidelines recommend PLND when risk for nodal disease is ≥2%.

METHODS

Data regarding all robot-assisted radical prostatectomy (RARP) (March 2012-October 2020) were prospectively collected, including patient, and surgeon characteristics. Univariate and multivariate analyses of PLND rate and lymph node involvement (LN+) were performed.

RESULTS

Among 8,591 men undergoing RARP for intermediate-risk PCa, 80.2% were performed with PLND (n = 6883), of which 2.9% were LN+ (n = 198). According to the current AUA risk stratification system, 1.2% of favorable intermediate-risk PCa and 4.7% of unfavorable intermediate-risk PCa demonstrated LN+. There were also differences in the LN+ rates among the subgroups of favorable (0.0%-1.3%), and unfavorable (3.5%-5.0%) categories. Additional factors associated with higher LN+ rates include ≥50% cores positive, ≥35% involvement at any core, and unfavorable genomic classifier result, none of which contribute to the favorable/unfavorable subgroups.

CONCLUSION

These data support PLND at RARP for all patients with unfavorable intermediate-risk PCa. Our data also indicate patients with favorable intermediate-risk prostate cancer at greatest risk for LN+ are those with ≥50% cores positive, ≥35% involvement at any core, and/or unfavorable genomic classifier result.

Peritoneal flap for lymphocele prophylaxis following robotic-assisted laparoscopic radical prostatectomy with pelvic lymph node dissection: study protocol and trial update for the randomized controlled PELYCAN study

Background

Data from interventional studies suggest that a peritoneal flap after pelvic lymph node dissection (LND) during laparoscopic, robotic-assisted radical prostatectomy (RARP) may reduce the rate of symptomatic lymphoceles in transperitoneal approach. However, most of these studies are not conducted in a randomized controlled fashion, thus limiting their scientific value. A recent prospective, randomized, controlled trial (RCT) did not show superiority of a peritoneal flap while further trials are lacking. Therefore, the aim of the presented RCT will be to show that creating a peritoneal flap decreases the rate of symptomatic lymphoceles compared to the current standard procedure without creation of a flap.

Methods/design

PELYCAN is a parallel-group, patient- and assessor-blinded, phase III, adaptive randomized controlled superiority trial. Men with histologically confirmed prostate cancer who undergo transperitoneal RARP with pelvic LND will be randomly assigned in a 1:1 ratio to two groups—either with creating a peritoneal flap (PELYCAN) or without creating a peritoneal flap (control). Sample size calculation yielded a sample size of 300 with a planned interim analysis after 120 patients, which will be performed by an independent statistician. This provides a possibility for early stopping or sample size recalculation.

Patients will be stratified for contributing factors for the development of postoperative lymphoceles. The primary outcome measure will be the rate of symptomatic lymphoceles in both groups within 6 months postoperatively. Patients and assessors will be blinded for the intervention until the end of the follow-up period of 6 months. The surgeon will be informed about the randomization result after performance of vesicourethral anastomosis. Secondary outcome measures include asymptomatic lymphoceles at the time of discharge and within 6 months of follow-up, postoperative complications, mortality, re-admission rate, and quality of life assessed by the EORTC QLQ-C30 questionnaire.

Discussion

The PELYCAN study is designed to assess whether the application of a peritoneal flap during RARP reduces the rate of symptomatic lymphoceles, as compared with the standard operation technique. In case of superiority of the intervention, this peritoneal flap may be suggested as a new standard of care.

Trial registration

German Clinical Trials Register DRKS00016794. Registered on 14 May 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05168-x.

Clinical Importance of a Peritoneal Interposition Flap to Prevent Symptomatic Lymphoceles after Robot-Assisted Radical Prostatectomy and Pelvic Lymph Node Dissection: A Systematic Review and Meta-Analysis

BACKGROUND

Robot-assisted radical prostatectomy (RARP) including pelvic lymph node dissection (PLND) is the current state of the art in surgical therapy of localized prostate cancer with intermediate or high risk. PLND in particular is associated with morbidity inherent to this method; the rate of symptomatic lymphoceles (sLCs), for example, ranges up to 10%.

OBJECTIVE

Various intraoperative modifications have been developed with the aim of reducing the sLC rate. Based on current studies, a peritoneal interposition flap (PIF) appears to be one of the most effective methods for this purpose. Under the criteria of a systematic review, 5 retrospective studies have been identified until now, 4 of which showed a positive effect of PIF on the sLC rate.

RESULTS AND LIMITATIONS

A total of 1,308 patients were included in the aggregated analysis of these 5 studies. The amount of sLCs was 1.3% (8/604) and 5.7% (40/704) in the PIF and standard groups, respectively (p < 0.001). The resulting odds ratio (OR) was 0.23 (95% confidence interval [CI]: 0.05-0.99), taking in-to account a noteworthy heterogeneity of the 5 studies (Q = 9.47, p = 0.05; I2 = 58%). In addition, a prospective randomized and blinded study (Pianoforte trial) with corresponding sLC rates of 8.3% (9/108) versus 9.7% (12/124) (p = 0.820) exists. In this study, the OR was 0.85 (95% CI: 0.34-2.10, p = 0.722).

CONCLUSION

Despite positive results from retrospective studies with indirect evidence, the role of the PIF in the reduction of sLC in RARP could not be conclusively assessed yet. The results of the first prospective randomized study do not show a positive effect of PIF, declaring a research gap for further studies with direct evidence.

The effect of peritoneal re-approximation on lymphocele formation in transperitoneal robot-assisted radical prostatectomy and extended pelvic lymphadenectomy

OBJECTIVE

The objective of the study was to evaluate the effect of peritoneal re-approximation at the end of the procedure in transperitoneal robot-assisted radical prostatectomy (tRARP) and extended pelvic lymphadenectomy (ePLND) on operative, oncologic, and symptomatic lymphocele rates.

MATERIAL AND METHODS

A total of 79 patients were included in the study who underwent tRARP and bilateral ePLND performed by two different experienced surgeons. One of the surgeons performed the peritoneal re-approximation (Group 1, n=41) and the other did not re-approximate the peritoneum (Group 2, n=38) at the end of the procedure in tRARP and ePLND. Operative parameters and symptomatic lymphocele rates were compared between the groups.

RESULTS

There were no significant differences between the preoperative parameters age, body mass index, and preoperative prostate-specific antigen values (p>0.05). The perioperative parameters were as follows: the operation time and estimated blood loss (EBL) was less, and the number of removed lymph nodes was higher in Group 2. However, only the difference in the EBL was statistically significant (p=0.03). Hospitalization time, symptomatic lymphocele, intervention requiring lymphocele, and complication rates were found to be less in Group 2, but only hospitalization time was statistically significant (p=0.04). Pathological parameters were similar for both groups. There was a significant correlation between lymph node positivity and the presence of symptomatic lymphocele in the correlation analysis (p=0.05).

CONCLUSION

It has been shown in this study that the re-approximation of the peritoneum does not provide any additional benefit in terms of complications. Considering that this process also increases the operation time and lymphocele formation, we think there is no need for re-approximation after robot-assisted radical prostatectomy and pelvic lymphadenectomy.