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

Can Negative Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography Avoid the Need for Pelvic Lymph Node Dissection in Newly Diagnosed Prostate Cancer Patients? A Systematic Review and Meta-analysis with Backup Histology as Reference Standard

CONTEXT

The role of positron emission tomography/computed tomography (PET/CT) with prostate-specific membrane antigen (PSMA) in the primary staging for patients with prostate cancer (PCa) is still debated.

OBJECTIVE

To analyze published studies reporting the accuracy of PSMA PET/CT for detecting lymph node invasion (LNI) at pelvic lymph node dissection (PLND).

EVIDENCE ACQUISITION

A search of PubMed/MEDLINE, Cochrane library's Central, EMBASE and Scopus databases, from inception to May 2021, was conducted. The primary outcome was to evaluate the sensitivity, specificity, positive (PPV) and negative (NPV) predictive values of PSMA PET/CT in detecting LNI on a per-patient level. As a secondary outcome, NPV of PET PSMA was tested on a per-node-level analysis. Detection rates were pooled using random-effect models. Preplanned subgroup analyses tested the diagnostic accuracy after stratification for the preoperative risk group. PPV and NPV variation over LNI prevalence was evaluated. Only studies including extended PLND (ePLND) as the reference standard test were included.

EVIDENCE SYNTHESIS

Twenty-seven studies, with a total of 2832 participants, were included in quantitative synthesis. The sensitivity, specificity, PPV, and NPV of PSMA PET/CT for LNI were, respectively, 58% (95% confidence interval [CI] 50-66%), 95% (95% CI 93-97%), 79% (95% CI 72-85%), and 87% (95% CI 84-89%), with overall moderate heterogeneity between studies. At bivariate analysis, the diagnostic accuracy of PSMA PET/CT estimated through summary receiver operating characteristic-derived area under the curve was 84% (95% CI 81-87%). On a per-node level, NPV of PET PSMA was 97% (95% CI 96-99%). At subgroup analyses, according to preoperative risk groups, sensitivity, specificity, PPV, and NPV were 51%, 93%, 73%, and 81%, respectively, in high-risk patients. Over the LNI prevalence range of 5-40%, PPV increased from 59% to 91%, while NPV decreased from 99% to 84%.

CONCLUSIONS

PSMA PET/CT scan provides promising accuracy in the field of primary nodal staging for PCa. The high NPV in men with a lower risk of LNI might be clinically useful to reduce the number of unnecessary PLND procedures performed. Conversely, in high-risk patients, negative PSMA PET/CT cannot replace staging ePLND.

PATIENT SUMMARY

In this systematic review and meta-analysis, we demonstrated that prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) scan may optimize the primary nodal staging and surgical management of prostate cancer patients candidate to radical prostatectomy. The high negative predictive value in men with a lower risk of lymph node invasion might be clinically useful for reducing the number of useless pelvic lymph node dissection (PLND) procedures performed. Conversely, in high-risk patients, negative PSMA PET/CT cannot allow avoiding of PLND.

A Protocol for the Development of the Intraoperative Complications Assessment and Reporting With Universal Standards Criteria: The ICARUS Project

Introduction

Perioperative complications, especially intraoperative adverse events (iAEs), carry significant potential for long-term sequelae in a patient's postoperative course. These events represent a substantial gap in contemporary surgical literature, with only a fraction of publications reporting intraoperative complications as outcomes of interest. To date, there is no universal standard for comprehensively reporting intraoperative complications in surgical practice and literature beyond the systems developed for grading individual events. We aim to establish a set of best-practice criteria for iAE reporting known as the Intraoperative Complication Assessment and Reporting with Universal Standards (ICARUS) Guidelines.

Methods and analysis

We will generate the ICARUS reporting guidelines using the EQUATOR Network development framework and the SQUIRE Guidelines. The initial step involves an umbrella review and meta-analysis of systemic reviews (SRs) assessing the perioperative adverse events of common surgeries. Measures for assessing, collecting, grading, and reporting the iAEs will be merged into a comprehensive list of criteria. Using a modified Delphi methodology, a team of expert surgeons (≥ 200 inpatient procedures/years) will contribute to and evaluate the proposed reporting guidelines. The panel will evaluate both the clinical usefulness and quality assessment and improvement utility of each criterion using a 5-point Likert. We expect multiple survey rounds until consensus regarding the utility of the guidelines is reached.

Dissemination

We plan to share then validate the newly developed guidelines within each surgical field. Dissemination will involve publicly shared guidelines, simultaneous journal publications, conference presentations, encouragement for journal endorsement, and application for inclusion in the Equator Network database. The study team plans to continue collecting feedback for future extension of the intraoperative reporting guidelines.

Highlights

Intraoperative adverse events are underreported and lack homogeneity in surgical literatureWe aim to use a modified Delphi methodology to develop the consensus-based, intraoperative complications assessment and reporting with universal standards (ICARUS) guidelinesWe will disseminate the ICARUS guidelines through journal publications and presentations at national and international meetings; journals and professional organizations will be encouraged to endorse the ICARUS guidelines.