Extended Versus Limited Pelvic Lymph Node Dissection During Radical Prostatectomy for Intermediate- and High-risk Prostate Cancer: Early Oncological Outcomes from a Randomized Phase 3 Trial

Utility of Machine Learning Models to Predict Lymph Node Metastasis of Japanese Localized Prostate Cancer

BACKGROUND/OBJECTIVES

Extended pelvic lymph node dissection is a crucial surgical technique for managing intermediate to high-risk prostate cancer. Accurately predicting lymph node metastasis before surgery can minimize unnecessary lymph node dissections and their associated complications. This study assessed the efficacy of various machine learning models for predicting lymph node metastasis in a cohort of Japanese patients who underwent robot-assisted laparoscopic radical prostatectomy.

METHODS

Data from 625 patients who underwent extended pelvic lymph node dissection or standard dissection with lymph node metastasis between October 2010 and February 2023 were analyzed. Four machine learning models-Random Forest, Light Gradient-Boosting Machine, Logistic Regression, and Support Vector Machine-were used to predict lymph node metastasis. Their performance was assessed using receiver operating characteristic curves, a decision curve analysis, and predictive values at different thresholds.

RESULTS

Lymph node metastasis was observed in 34 patients (5.4%). The Light Gradient-Boosting Machine had the highest AUC of 0.924, followed by the Random Forest model with an AUC of 0.894. The decision curve analysis indicated substantial net benefits for both models, particularly at low threshold probabilities. The Light Gradient-Boosting Machine demonstrated superior accuracy, achieving 95.6% at the 0.05 threshold and 96.7% at the 0.10 threshold, outperforming other models and conventional nomograms in the validation dataset.

CONCLUSION

Machine learning models, especially Light Gradient-Boosting Machine and Random Forest, show significant potential for predicting lymph node metastasis in prostate cancer, thereby aiding in reducing unnecessary surgical interventions.

Optimization of Extended Pelvic Lymph Node Dissection Side for Prostate Cancer

BACKGROUND

This study aimed to show the association between tumor location and laterality of positive lymph nodes by evaluating biopsy and magnetic resonance imaging (MRI) findings, and to optimize the extended pelvic lymph node dissection (ePLND) side for prostate cancer.

METHODS

The study enrolled patients who underwent robot-assisted radical prostatectomy with ePLND. Tumor locations were determined according to International Society of Urological Pathology grade group 4/5 in biopsies and Prostate Imaging-Reporting and Data System category 4/5 in MRI results. The concordance of tumor location lobe and positive lymph node side with the performance of tumor location-guided ePLND for positive lymph node detection was evaluated.

RESULTS

For 301 patients who underwent ePLND at Kyushu University Hospital, tumor locations determined by biopsy and MRI findings showed no lesion in 8 (2.7%) patients, unilateral lobe in 223 (74.1%) patients, and bilateral lobe in 70 (23.3%) patients. The accuracies for detection of any and all positive lymph nodes by tumor location-guided unilateral ePLND were 99.6% and 97.3%, respectively. Among the patients at St. Luke's International Hospital, the accuracies for detection of any and all positive lymph nodes by tumor location-guided unilateral ePLND were estimated to be 99.0% and 97.3%, respectively.

CONCLUSIONS

This study proposed tumor location-guided ePLND according to biopsy and MRI findings. This novel strategy is expected to reduce the burden of bilateral ePLND at the cost of acceptable risk of failing to detect positive lymph nodes.

Japanese expert consensus on the standardization of robot-assisted pelvic lymph node dissection in urological surgery: Extent of pelvic lymph node and surgical technique

Pelvic lymph node dissection (PLND) is important for accurate staging and prognosis of prostate and/or bladder cancer. Several guidelines recommend extended PLND for patients with these cancers. However, the therapeutic benefits of extended PLND are unclear. One major reason is that the extent of PLND is not clearly defined. Thus, the working group for standardization of robot-assisted PLND, including nine experienced urologists for PLND in Japan, was launched in January 2023 by the Japanese Society of Endourology and Robotics. This study summarized the discussions to define the individual extent of PLND in urological surgery in a consensus meeting among these experienced urologists. The consensus meeting determined the extent of PLND based on arteries (veins) and anatomical membrane structures rather than a vague concept or approach toward PLND. This concept is expected to allow surgeons to implement the same extent of PLND. Finally, after a total of 10 online web conferences were held, we determined the extent of PLND for the obturator lymph node (LN) area, the internal iliac LN area, the external and common iliac LN area, and the presacral LN area according to the above rules. The extent of PLND suggested here currently does not have a clear therapeutic rationale. Therefore, the extent of our proposed PLND is by no means mandatory. We hope our definition of the extent of PLND will be supported by further evidence of therapeutic benefits for urologic cancers.

Japanese clinical practice guidelines for prostate cancer 2023

This fourth edition of the Japanese Clinical Practice Guidelines for Prostate Cancer 2023 is compiled. It was revised under the leadership of the Japanese Urological Association, with members selected from multiple academic societies and related organizations (Japan Radiological Society, Japanese Society for Radiation Oncology, the Department of EBM and guidelines, Japan Council for Quality Health Care (Minds), Japanese Society of Pathology, and the patient group (NPO Prostate Cancer Patients Association)), in accordance with the Minds Manual for Guideline Development (2020 ver. 3.0). The most important feature of this revision is the adoption of systematic reviews (SRs) in determining recommendations for 14 clinical questions (CQs). Qualitative SRs for these questions were conducted, and the final recommendations were made based on the results through the votes of 24 members of the guideline development group. Five algorithms based on these results were also created. Contents not covered by the SRs, which are considered textbook material, have been described in the general statement. In the general statement, a literature search for 14 areas was conducted; then, based on the general statement and CQs of the Japanese Clinical Practice Guidelines for Prostate Cancer 2016, the findings revealed after the 2016 guidelines were mainly described. This article provides an overview of these guidelines.

French AFU Cancer Committee Guidelines - Update 2024-2026: Prostate cancer - Diagnosis and management of localised disease

OBJECTIVE

The aim of the Oncology Committee of the French Urology Association is to propose updated recommendations for the diagnosis and management of localized prostate cancer (PCa).

METHODS

A systematic review of the literature from 2022 to 2024 was conducted by the CCAFU on the elements of diagnosis and therapeutic management of localized PCa, evaluating references with their level of evidence.

RESULTS

The recommendations set out the genetics, epidemiology and diagnostic methods of PCa, as well as the concepts of screening and early detection. MRI, the reference imaging test for localized cancer, is recommended before prostate biopsies are performed. Molecular imaging is an option for disease staging. Performing biopsies via the transperineal route reduces the risk of infection. Active surveillance is the standard treatment for tumours with a low risk of progression. Therapeutic methods are described in detail, and recommended according to the clinical situation.

CONCLUSION

This update of French recommendations should help to improve the management of localized PCa.

Evaluation of complications and biochemical recurrence rates after (super) extended lymph node dissection during radical prostatectomy

OBJECTIVE

To evaluate the effectiveness of extended (e-PLND) and super-extended pelvic lymph node dissection (se-PLND) during robot-assisted radical prostatectomy (RARP) by examining lymph node (LN) yield, complications, LN metastasis, and biochemical recurrence (BCR) incidence.

METHODS

Between January 2016 and January 2020, 354 consecutive patients with > 5% risk of lymph node involvement (LNI), as predicted by the Memorial Sloan Kettering Cancer Center nomogram, underwent RARP with (s)e-PLND at a high-volume center. The e-PLND involved removing fibrofatty lymphatic tissue around the obturator fossa, internal iliac region, and external iliac vessels. The se-PLND, performed at the discretion of the surgeons, also included lymph nodes from the pre-sacral and common iliac regions. Outcomes included histopathological findings by anatomical region; complications; and BCR incidence during follow-up.

RESULTS

The median LNI risk was 18% (IQR 9-31%). A median of 22 LN (IQR 16-28) were removed, with se-PLND yielding a higher number: 25 (IQR 20-32) compared to e-PLND: 17 (IQR 13-24) (p < 0.001). pN1 disease was detected in 22% of patients overall, higher in se-PLND (29%) than e-PLND (14%) (p < 0.001). Of metastatic LNs, 14% were situated outside the e-PLND template. Operation time was longer for se-PLND, but perioperative complications were similar between both groups. After a median follow-up of 24 months (IQR 7-33), BCR incidence was comparable between the two groups.

CONCLUSION

Compared to standard extended pelvic lymph node dissection (PLND), super extended PLND increases lymph node yield and removal of metastatic deposits but does not contribute to progression free survival at mid-term.

Multi-stage mechanisms of tumor metastasis and therapeutic strategies

The cascade of metastasis in tumor cells, exhibiting organ-specific tendencies, may occur at numerous phases of the disease and progress under intense evolutionary pressures. Organ-specific metastasis relies on the formation of pre-metastatic niche (PMN), with diverse cell types and complex cell interactions contributing to this concept, adding a new dimension to the traditional metastasis cascade. Prior to metastatic dissemination, as orchestrators of PMN formation, primary tumor-derived extracellular vesicles prepare a fertile microenvironment for the settlement and colonization of circulating tumor cells at distant secondary sites, significantly impacting cancer progression and outcomes. Obviously, solely intervening in cancer metastatic sites passively after macrometastasis is often insufficient. Early prediction of metastasis and holistic, macro-level control represent the future directions in cancer therapy. This review emphasizes the dynamic and intricate systematic alterations that occur as cancer progresses, illustrates the immunological landscape of organ-specific PMN creation, and deepens understanding of treatment modalities pertinent to metastasis, thereby identifying some prognostic and predictive biomarkers favorable to early predict the occurrence of metastasis and design appropriate treatment combinations.

Progress of fluorescence imaging in lymph node dissection surgery for prostate and bladder cancer

Fluorescence imaging is a relatively new imaging method used to visualize different tissue structures to help guide intraoperative operations, which has potential advantages with high sensitivity and contrast compared to conventional imaging. In this work, we review fluorescent contrast agents and devices used for lymphatic system imaging. Indocyanine green is the most widely utilized due to its high sensitivity, specificity, low background fluorescence, and safety profile. In prostate and bladder cancer lymph node dissection, the complex lymphatic drainage can result in missed metastatic nodes and extensive dissection increases the risk of complications like lymphocele, presenting a significant challenge for urologists. Fluorescence-guided sentinel lymph node dissection facilitates precise tumor staging. The combination of fluorescence and radiographic imaging improves the accuracy of lymph node staging. Multimodal imaging presents new potential for precisely identifying metastatic pelvic lymph nodes.

Feasibility of Using a Novel Drop-In Gamma Probe for 99m Tc-PSMA-I&S-Guided Lymph Node Detection During Robot-Assisted Radical Prostatectomy for Primary Prostate Cancer

PURPOSE

Prostate-specific membrane antigen (PSMA)-targeted radioguided surgery (RGS) has gained increased interest in prostate cancer (PCa). This analysis aims to evaluate the feasibility, safety, and limitations of RGS with a novel drop-in gamma probe in primary PCa.

PATIENTS AND METHODS

The data of 13 patients with primary PCa undergoing RGS were analyzed retrospectively. After preoperative administration of 99m Tc-PSMA-I&S, a SPECT/CT was conducted and a robotic radical prostatectomy was performed the following day including intraoperative assessment of the lymph node stations using a novel robotic drop-in gamma probe. This was followed by an extended pelvic lymph node dissection (ePLND) with ex vivo control measurement using the drop-in and a conventional rigid gamma probe.

RESULTS

Eleven patients (median PSA value of 11 ng/mL) had high-risk and 2 patients had intermediate-risk PCa. Overall, a median of 22 ePLND lymph nodes were dissected. In 1 patient, preoperative SPECT/CT imaging showed suspicious lymph nodes, which could be confirmed intraoperatively with the robotic drop-in probe and subsequently in the final histopathological analysis. RGS failed to identify 2 patients with micrometastases (<3 mm) preoperatively and intraoperatively. No postoperative complications related to 99m Tc-PSMA-I&S RGS or ePLND occurred.

CONCLUSIONS

RGS with the novel drop-in gamma probe and 99m Tc-PSMA-I&S allows for a reliable intraoperative screening for lymph node metastases in robot-assisted radical prostatectomy for primary PCa with an acceptable safety profile. However, limitations in the detection of micrometastases need to be overcome before omitting extended ePLND in patients at risk for lymphatic spread.

EAU-EANM-ESTRO-ESUR-ISUP-SIOG Guidelines on Prostate Cancer-2024 Update. Part I: Screening, Diagnosis, and Local Treatment with Curative Intent

BACKGROUND AND OBJECTIVE

The European Association of Urology (EAU)-European Association of Nuclear Medicine (EANM)-European Society for Radiotherapy and Oncology (ESTRO)-European Society of Urogenital Radiology (ESUR)-International Society of Urological Pathology (ISUP)-International Society of Geriatric Oncology (SIOG) guidelines provide recommendations for the management of clinically localised prostate cancer (PCa). This paper aims to present a summary of the 2024 version of the EAU-EANM-ESTRO-ESUR-ISUP-SIOG guidelines on the screening, diagnosis, and treatment of clinically localised PCa.

METHODS

The panel performed a literature review of all new data published in English, covering the time frame between May 2020 and 2023. The guidelines were updated, and a strength rating for each recommendation was added based on a systematic review of the evidence.

KEY FINDINGS AND LIMITATIONS

A risk-adapted strategy for identifying men who may develop PCa is advised, generally commencing at 50 yr of age and based on individualised life expectancy. The use of multiparametric magnetic resonance imaging in order to avoid unnecessary biopsies is recommended. When a biopsy is considered, a combination of targeted and regional biopsies should be performed. Prostate-specific membrane antigen positron emission tomography imaging is the most sensitive technique for identifying metastatic spread. Active surveillance is the appropriate management for men with low-risk PCa, as well as for selected favourable intermediate-risk patients with International Society of Urological Pathology grade group 2 lesions. Local therapies are addressed, as well as the management of persistent prostate-specific antigen after surgery. A recommendation to consider hypofractionation in intermediate-risk patients is provided. Patients with cN1 PCa should be offered a local treatment combined with long-term intensified hormonal treatment.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The evidence in the field of diagnosis, staging, and treatment of localised PCa is evolving rapidly. These PCa guidelines reflect the multidisciplinary nature of PCa management.

PATIENT SUMMARY

This article is the summary of the guidelines for "curable" prostate cancer. Prostate cancer is "found" through a multistep risk-based screening process. The objective is to find as many men as possible with a curable cancer. Prostate cancer is curable if it resides in the prostate; it is then classified into low-, intermediary-, and high-risk localised and locally advanced prostate cancer. These risk classes are the basis of the treatments. Low-risk prostate cancer is treated with "active surveillance", a treatment with excellent prognosis. For low-intermediary-risk active surveillance should also be discussed as an option. In other cases, active treatments, surgery, or radiation treatment should be discussed along with the potential side effects to allow shared decision-making.

Ga68-PSMA PET for lymph node staging in intermediate and high-risk prostate cancer patients undergoing robotic assisted radical prostatectomy

BACKGROUND

In intermediate/high risk prostate cancer, preoperative staging exams are mandatory. The aim of these imaging studies is to evaluate eventual lymph nodes involvement and/or metastatic spread of the tumor. Nevertheless, computed tomography (CT), magnetic resonance imaging (MRI), bone scan modalities have controversial sensitivity. Introduction of PET-PSMA and its use also as preoperative exam, seems to improve diagnostic accuracy due to favorable negative predictive value. The aim of this study was to evaluate the accuracy of PET-PSMA as a preoperative staging exam and its accuracy in predicting lymph nodes involvement in intermediate/high risk prostate cancer (PCa) patients.

METHODS

A retrospective analysis of 50 patients diagnosed with intermediate/high risk PCa between 2018 and 2022 has been performed. All patients underwent preoperative 68Ga-PSMA PET/CT prior to robot-assisted radical prostatectomy (RARP) + extended pelvic lymph node dissection (ePLND). The cohort was categorized into two groups: pathologically negative lymph nodes (pN0) vs. positive nodes (pN1). A descriptive and comparative analysis was conducted. Correlation analysis between continuous variables was performed using the Spearman's Rank Test. Using lymph nodes histopathological results as reference standard, the diagnostic performance of 68Ga-PSMA PET/CT was calculated.

RESULTS

Overall, 50 patients were included. The mean age was 63.3 years with a median prostatic specific antigen (PSA) of 7.7 ng/dL. Forty-four percent of the patients exhibited an International Society of Urological Pathology (ISUP) score of 4 or higher, and 28% had a pT3 stage. Overall, 43 (86%) patients submitted to ePLND did not present lymph node metastases (pN0), while 8 (14%) patients were pN1. PET-PSMA showed low sensitivity in detecting lymph node metastases (25%) while a high specificity in excluding lymph-node disease (88.1%) has been observed. Finally, we noted a significant positive correlation between the total SUVmax of the prostate and the initial total PSA (r=0.38; P=0.019), as well as the percentage of tumor involvement (r=0.383; P=0.022).

CONCLUSIONS

Evidence on the role of PET-PSMA in the primary staging of PCa is steadily building up. A positive correlation between SUV and prostate involvement indicates that PET-PSMA could reflect, with a good approximation, the pathological features of the prostate. However, the low sensitivity depicted remains the main limitation. Future prospective studies are needed to determine the impact on patient outcome.

Quantitative PSMA-PET parameters in localized prostate cancer: prognostic and potential predictive value

BACKGROUND

PSMA-PET is increasingly used for staging prostate cancer (PCA) patients. However, it is not clear if quantitative imaging parameters of positron emission tomography (PET) have an impact on disease progression and are thus important for the prognosis of localized PCA.

METHODS

This is a monocenter retrospective analysis of 86 consecutive patients with localized intermediate or high-risk PCA and PSMA-PET before treatment The quantitative PET parameters maximum standardized uptake value (SUVmax), tumor asphericity (ASP), PSMA tumor volume (PSMA-TV), and PSMA total lesion uptake (PSMA-TLU = PSMA-TV × SUVmean) were assessed for their prognostic significance in patients with radiotherapy or surgery. Cox regression analyses were performed for biochemical recurrence-free survival, overall survival (OS), local control, and loco-regional control (LRC).

RESULTS

67% of patients had high-risk disease, 51 patients were treated with radiotherapy, and 35 with surgery. Analysis of metric PET parameters in the whole cohort revealed a significant association of PSMA-TV (p = 0.003), PSMA-TLU (p = 0.004), and ASP (p < 0.001) with OS. Upon binarization of PET parameters, several other parameters showed a significant association with clinical outcome. When analyzing high-risk patients according to the primary treatment approach, a previously published cut-off for SUVmax (8.6) showed a significant association with LRC in surgically treated (p = 0.048), but not in primary irradiated (p = 0.34) patients. In addition, PSMA-TLU (p = 0.016) seemed to be a very promising biomarker to stratify surgical patients.

CONCLUSION

Our data confirm one previous publication on the prognostic impact of SUVmax in surgically treated patients with high-risk PCA. Our exploratory analysis indicates that PSMA-TLU might be even better suited. The missing association with primary irradiated patients needs prospective validation with a larger sample size to conclude a predictive potential. Trial registration Due to the retrospective nature of this research, no registration was carried out.

Prognosis based on postoperative PSA levels and treatment in prostate cancer with lymph node involvement

BACKGROUND

The therapeutic role of pelvic lymph node dissection (PLND) during radical prostatectomy (RP) for prostate cancer is not established. In clinical practice, PLND is primarily performed in cases of high-risk prostate cancer. The detection of lymph node metastasis plays a crucial role in determining the need for subsequent treatments. This study aims to evaluate the prognosis of prostate cancer patients with lymph node involvement (LNI) by stratifying them based on postoperative prostate-specific antigen (PSA) levels to identify biomarkers that can guide postoperative treatment strategies.

METHODS

Analysis was conducted on 383 patients, selected from 572 initially eligible, who underwent RP with LNI across 33 Japanese Urological Oncology Group institutions from 2006 to 2019. Patients were grouped according to postoperative PSA levels and salvage treatments received. Follow-up focused on castration resistance-free survival (CRFS), metastasis-free survival (MFS), and overall survival (OS).

RESULTS

In the persistent PSA group (PSA ≥ 0.1 ng/mL), CRFS and MFS were significantly shorter compared to the non-persistent PSA group (PSA < 0.1 ng/mL), and there was a tendency for shorter OS. In the persistent PSA group, patients with postoperative PSA values above the median (PSA ≥ 0.52 ng/mL) showed shorter CRFS and MFS. Furthermore, in the PSA ≥ 0.52 group, androgen deprivation therapy (ADT) plus radiotherapy (RT) combination had prolonged CRFS and MFS compared with ADT alone.

CONCLUSIONS

This study provides valuable insights into stratifying patients based on postoperative PSA levels to tailor postoperative treatment strategies, potentially improving the prognosis of prostate cancer patients with LNI.

Treatment and Staging Intensification Strategies Associated with Radical Prostatectomy for High-Risk Prostate Cancer: Efficacy Evaluation and Exploration of Novel Approaches

The management of high-risk prostate cancer (PCa) presents a significant clinical challenge, often necessitating treatment intensification due to the potential presence of micrometastases. While radical prostatectomy (RP) constitutes one of the primary treatment modalities, the integration of neoadjuvant and adjuvant therapies suggests a paradigm shift towards more aggressive treatment strategies, also guided by new imaging modalities like positron emission tomography using prostate-specific membrane antigen (PSMA-PET). Despite the benefits, treatment intensification raises concerns regarding increased side effects. This review synthesizes the latest evidence on perioperative treatment intensification and de-escalation for high-risk localized and locally advanced PCa patients eligible for surgery. Through a non-systematic literature review conducted via PubMed, Scopus, Web of Science, and ClinicalTrials.gov, we explored various dimensions of perioperative treatments, including neoadjuvant systemic therapies, adjuvant therapies, and the role of novel diagnostic technologies. Emerging evidence provides more support for neoadjuvant systemic therapies. Preliminary results from studies suggest the potential for treatments traditionally reserved for metastatic PCa to show apparent benefit in a non-metastatic setting. The role of adjuvant treatments remains debated, particularly the use of androgen deprivation therapy (ADT) and adjuvant radiotherapy in patients at higher risk of biochemical recurrence. The potential role of radio-guided PSMA lymph node dissection emerges as a cutting-edge approach, offering a targeted method for eradicating disease with greater precision. Innovations such as artificial intelligence and machine learning are potential game-changers, offering new avenues for personalized treatment and improved prognostication. The intensification of surgical treatment in high-risk PCa patients is a dynamic and evolving field, underscored by the integration of traditional and novel therapeutic approaches. As evidence continues to emerge, these strategies will refine patient selection, enhance treatment efficacy, and mitigate the risk of progression, although with an attentive consideration of the associated side effects.

Analysis of biopsy pathology and risk factors of lymph node metastasis in prostate cancer

OBJECTIVE

To explore the relationship between biopsy pathology and lymph node metastasis in patients with prostate cancer (PCa), and to identify risk factors of lymph node metastasis (LNM).

PATIENTS AND METHODS

Patients diagnosed with prostate cancer were respective screened between Jan 2015 and May 2022. Patients diagnosed PCa via 13-core ultrasound-guided biopsies and underwent radical prostatectomy and lymph node dissection were identified. The clinicopathological characteristics of the patients were recorded. Relationships between LNM and non-LNM were analyzed using chi-square and independent samples t-test. Logistic regression model was fitted to analyze the risk factors of lymph node metastases.

RESULTS

Two hundreds and fifteen patients were included, sixty-seven patients had lymph node metastasis. Gleason scores in LNM group were higher than that in non-LNM group (8.5 ± 0.9 VS 7.5 ± 1.5, p < 0.001), positive biopsy in non-LNM group was significantly lower than that in LNM group (p < 0.001), Binary logistic regression analysis indicated number of positive biopsy and number of removed lymph nodes increased the risks of LNM (odds ratio, OR = 1.28, 95% confidence interval, CI = 1.16-1.42, p < 0.001; OR = 1.11, 95% CI = 1.06-1.17, p < 0.001; respectively). Number of positive biopsy in internal gland but not external gland was significant associated with LNM (OR = 1.66, 95% CI = 1.34-2.06, p < 0.001; OR = 1.19, 95% CI = 0.88-1.61, p = 0.262; respectively). The patients with lymph nodes dissection more than 13 were about four times more likely to detect lymph node metastasis than those fewer than 13 (OR = 3.92, 95% CI = 2.10-7.33, p < 0.001).

CONCLUSIONS

The risk of lymph node metastasis increased with the number of positive prostate biopsy cores, and tumors in the internal gland were more likely to cause lymph node metastasis. In addition, lymph node metastasis was more likely to be found when the number of lymph nodes dissection was greater than 13.

Robot-assisted Radical Prostatectomy with the KangDuo Surgical System Versus the da Vinci Si System: A Prospective, Double-center, Randomized Controlled Trial

BACKGROUND

The KangDuo Surgical Robot (KD-SR) is a newly developed surgical robot.

OBJECTIVE

To compare the safety and efficacy of robot-assisted radical prostatectomy (RARP) using the KD-SR with those of the da Vinci Si Surgical System (DV-SS-Si).

DESIGN, SETTING, AND PARTICIPANTS

A prospective double-center noninferiority randomized controlled trial was conducted among 18-75-yr-old patients with suspected T1-2N0M0 prostate cancer (PCa) scheduled for RARP.

INTERVENTION

RARP with the KD-SR (KD-RARP) versus RARP with the DV-SS-Si (DV-RARP).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was surgical success, defined as follows: surgery can be performed according to the established protocol, without switching to other surgical modalities, and without secondary surgery due to surgical complications after surgery. The secondary outcome was short-term functional and oncological outcomes. The noninferiority threshold was set at 10%.

RESULTS AND LIMITATIONS

Eighty patients were enrolled, while the full analysis set finally included 79 patients (40 with KD-RARP and 39 with DV-RARP). The success rate was 100% in both groups. We could not find differences in urinary continence rate at 1, 2, 3, and 4 wk after catheter removal between the groups (p > 0.05). The rate of Clavien-Dindo grade II adverse events was 20% in the KD-RARP group and 17.9% in the DV-RARP group (p = 0.82), and no grade ≥III adverse events occurred. The median operation time was significantly longer in the KD-RARP group than in the DV-RARP group (177.5 vs 145 min, p = 0.012). The main limitations were the short follow-up period and that survival was not considered as the primary outcome.

CONCLUSIONS

The KD-SR is a viable option for RARP, with acceptable short-term outcomes compared with the DV-SS-Si for T1-2 PCa.

PATIENT SUMMARY

This is the first prospective randomized controlled trial to compare the KangDuo Surgical Robot (KD-SR) versus the da Vinci Si Surgical System (DV-SS-Si) for robot-assisted radical prostatectomy, which determines that the KD-SR is noninferior to the DV-SS-Si regarding safety and efficacy for T1-T2 prostate cancer.

Contemporary Role of Lymph Node Dissection in Genitourinary Cancers: Where Are We in 2023?

CONTEXT

Lymphadenectomy during surgery for genitourinary malignancies has varying benefits.

OBJECTIVE

To review contemporary evidence on lymph node dissection in genitourinary cancers.

EVIDENCE ACQUISITION

We performed a collaborative review to summarize current evidence supporting lymph node dissection in urothelial, prostate, kidney, penile, and testis cancers. We present the evidence on patient selection and recommended dissection templates, and highlight knowledge gaps and ongoing areas of investigation.

EVIDENCE SYNTHESIS

Lymph node dissection remains the reference standard for lymph node staging. Pathologic nodal stage informs prognosis and guides adjuvant treatment. Appropriate template and patient selection are paramount to optimize outcomes and capitalize on the selective therapeutic benefits.

CONCLUSIONS

Accurate staging with lymphadenectomy is contingent on appropriate template selection. The cumulative benefit will depend on judicious patient selection.

PATIENT SUMMARY

We performed a collaborative review by a diverse group of experts in urology. We reviewed current evidence on lymph node dissection.

Proficiency score as a predictor of early trifecta achievement during the learning curve of robot-assisted radical prostatectomy for high-risk prostate cancer: Results of a multicentric series

Background

Recently, an innovative tool called "proficiency score" was introduced to assess the learning curve for robot-assisted radical prostatectomy (RARP). However, the initial study only focused on patients with low-risk prostate cancer for whom pelvic lymph node dissection (PLND) was not required. To address this issue, we aimed to validate proficiency scores of a contemporary multicenter cohort of patients with high-risk prostate cancer treated with RARP plus extended PLND by trainee surgeons.

Material and methods

Between 2010 and 2020, 4 Italian institutional prostate-cancer datasets were merged and queried for "RARP" and "high-risk prostate cancer." High-risk prostate cancer was defined according to the most recent European Association of Urology guidelines as follows: prostate-specific antigen >20 ng/mL, International Society of Urological Pathology ≥4, and/or clinical stage (cT) ≥ 2c on preoperative imaging. The selected cohort (n = 144) included clinical cases performed by trainee surgeons (n = 4) after completing their RARP learning curve (50 procedures for low-risk prostate cancer). The outcome of interest, the proficiency score, was defined as the coexistence of all the following criteria: a comparable operation time to the interquartile range of the mentor surgeon at each center, absence of any significant perioperative complications Clavien-Dindo Grade 3-5, no perioperative blood transfusions, and negative surgical margins. A logistic binary regression model was built to identify the predictors of 1-year trifecta achievement in the trainee cohort. For all statistical analyses, a 2-sided p < 0.05 was considered significant.

Results

A proficiency score was achieved in 42.3% patients. At univariable level, proficiency score was associated with 1-year trifecta achievement (odds ratio, 8.77; 95% confidence interval, 2.42-31.7; p = 0.001). After multivariable adjustments for age, nerve-sparing, and surgical technique, the proficiency score independently predicted 1-year trifecta achievement (odds ratio, 9.58; 95% confidence interval, 1.83-50.1; p = 0.007).

Conclusions

Our findings support the use of proficiency scores in patients and require extended PLND in addition to RARP.

Prognostication in Lymph Node-Positive Prostate Cancer with No PSA Persistence After Radical Prostatectomy

BACKGROUND

This study aimed to create a prognostic model to predict disease recurrence among patients with lymph node involvement but no prostate-specific antigen (PSA) persistence and to explore its clinical utility.

METHODS

The study analyzed patients with lymph node involvement after pelvic lymph node dissection with radical prostatectomy in whom no PSA persistence was observed between 2006 and 2019 at 33 institutions. Prognostic factors for recurrence-free survival (RFS) were analyzed by the Cox proportional hazards model.

RESULTS

Among 231 patients, 127 experienced disease recurrence. The factors prognostic for RFS were PSA level at diagnosis (≥ 20 vs. < 20 ng/mL: hazard ratio [HR], 1.66; 95% confidence interval [CI], 1.09-2.52; P = 0.017), International Society of Urological Pathology grade group at radical prostatectomy (RP) specimen (group ≥ 4 vs. ≤ 3: HR, 1.63; 95% CI 1.12-2.37; P = 0.010), pathologic T-stage (pT3b/4 vs. pT2/3a: HR, 1.70; 95% CI 1.20-2.42; P = 0.0031), and surgical margin status (positive vs. negative: HR, 1.60; 95% CI 1.13-2.28; P = 0.0086). The prognostic model using four parameters were associated with RFS and metastasis-free survival.

CONCLUSION

The prognostic model in combination with postoperative PSA value and number of lymph nodes is clinically useful for discussing treatment choice with patients.

Photothermal therapy: a novel potential treatment for prostate cancer

Prostate cancer (PCa) is a leading cause of cancer-related death in men, and most PCa patients treated with androgen deprivation therapy will progress to metastatic castration-resistant prostate cancer (mCRPC) due to the lack of efficient treatment. Recently, lots of research indicated that photothermal therapy (PTT) was a promising alternative that provided an accurate and efficient prostate cancer therapy. A photothermic agent (PTA) is a basic component of PPT and is divided into organic and inorganic PTAs. Besides, the combination of PTT and other therapies, such as photodynamic therapy (PDT), immunotherapy (IT), chemotherapy (CT), etc., provides an more efficient strategy for PCa therapy. Here, we introduce basic information about PTT and summarize the PTT treatment strategies for prostate cancer. Based on recent works, we think the combination of PPT and other therapies provides a novel possibility for PCa, especially CRPC clinical treatment.

Faster both in operative time and functional recovery by the extraperitoneal daVinci SP-based robot-assisted radical prostatectomy: a propensity score matching analysis compared to transperitoneal multiport counterpart

We aim to investigate the peri-operative outcomes after extraperitoneal single-port based robot-assisted radical prostatectomy (eSP-RARP) utilizing the da Vinci SP system compared to conventional transperitoneal multi-port counterparts (tMP-RARP), in an era when pelvic lymph node dissection (PNLD) was omitted for the node-negative case. With exclusion criteria of volume  + 50 g, suspicious rectal invasion, and node-positive disease given relatively weak grasping power and limited range of motion from the current SP system, 50 consecutive patients (Since December 2021) with localized prostate cancer underwent eSP-RARP by a single urologist maintaining identical surgical technique for 100 consecutive tMP-RARP cases (Since December 2020). Given initial selection criteria, each group was matched to a 1:1 ratio based on the risk-stratification parameters and the prostate volume. The operative time, which was maintained in each group during the study period, was significantly faster in eSP-RARP groups than in tMP-RARP (149.2 vs. 163.2 min, p = 0.025), while the weight of the removed specimen (27.1 vs. 29.0 g, p = 0.420) and margin positivity (14.7% vs. 11.7% in pT2, p = 0.812) were similar. The gas-out (1.5 vs. 1.88 days, p = 0.003) and solid diet dates (2.26 vs. 3.22 days, p < 0.001) were faster in the eSP-RARP group. The single-pad continence dates (30.5 vs. 51.9 days, p = 0.145) and zero-pad continence dates (105.5 vs. 146.2 days, p = 0.210) were identical. 90-day single-pad continence rate was 92% vs. 82% (p = 0.142, 52% vs. 56% in zero-pad continence). Based on these, daVinci SP-based RARP restored bowel function faster with shorter operative time through an extraperitoneal approach than the conventional transperitoneal multi-port counterpart while maintaining similar incontinence outcomes in cases without a routine PNLD.

An artificial intelligence model for detecting pathological lymph node metastasis in prostate cancer using whole slide images: a retrospective, multicentre, diagnostic study

Background

The pathological examination of lymph node metastasis (LNM) is crucial for treating prostate cancer (PCa). However, the limitations with naked-eye detection and pathologist workload contribute to a high missed-diagnosis rate for nodal micrometastasis. We aimed to develop an artificial intelligence (AI)-based, time-efficient, and high-precision PCa LNM detector (ProCaLNMD) and evaluate its clinical application value.

Methods

In this multicentre, retrospective, diagnostic study, consecutive patients with PCa who underwent radical prostatectomy and pelvic lymph node dissection at five centres between Sep 2, 2013 and Apr 28, 2023 were included, and histopathological slides of resected lymph nodes were collected and digitised as whole-slide images for model development and validation. ProCaLNMD was trained at a dataset from a single centre (the Sun Yat-sen Memorial Hospital of Sun Yat-sen University [SYSMH]), and externally validated in the other four centres. A bladder cancer dataset from SYSMH was used to further validate ProCaLNMD, and an additional validation (human-AI comparison and collaboration study) containing consecutive patients with PCa from SYSMH was implemented to evaluate the application value of integrating ProCaLNMD into the clinical workflow. The primary endpoint was the area under the receiver operating characteristic curve (AUROC) of ProCaLNMD. In addition, the performance measures for pathologists with ProCaLNMD assistance was also assessed.

Findings

In total, 8225 slides from 1297 patients with PCa were collected and digitised. Overall, 8158 slides (18,761 lymph nodes) from 1297 patients with PCa (median age 68 years [interquartile range 64-73]; 331 [26%] with LNM) were used to train and validate ProCaLNMD. The AUROC of ProCaLNMD ranged from 0.975 (95% confidence interval 0.953-0.998) to 0.992 (0.982-1.000) in the training and validation datasets, with sensitivities > 0.955 and specificities > 0.921. ProCaLNMD also demonstrated an AUROC of 0.979 in the cross-cancer dataset. ProCaLNMD use triggered true reclassification in 43 (4.3%) slides in which micrometastatic tumour regions were initially missed by pathologists, thereby correcting 28 (8.5%) missed-diagnosed cases of previous routine pathological reports. In the human-AI comparison and collaboration study, the sensitivity of ProCaLNMD (0.983 [0.908-1.000]) surpassed that of two junior pathologists (0.862 [0.746-0.939], P = 0.023; 0.879 [0.767-0.950], P = 0.041) by 10-12% and showed no difference to that of two senior pathologists (both 0.983 [0.908-1.000], both P > 0.99). Furthermore, ProCaLNMD significantly boosted the diagnostic sensitivity of two junior pathologists (both P = 0.041) to the level of senior pathologists (both P > 0.99), and substantially reduced the four pathologists' slide reviewing time (-31%, P < 0.0001; -34%, P < 0.0001; -29%, P < 0.0001; and -27%, P = 0.00031).

Interpretation

ProCaLNMD demonstrated high diagnostic capabilities for identifying LNM in prostate cancer, reducing the likelihood of missed diagnoses by pathologists and decreasing the slide reviewing time, highlighting its potential for clinical application.

Funding

National Natural Science Foundation of China, the Science and Technology Planning Project of Guangdong Province, the National Key Research and Development Programme of China, the Guangdong Provincial Clinical Research Centre for Urological Diseases, and the Science and Technology Projects in Guangzhou.

18 F-prostate specific membrane antigen positron emission tomography/computerized tomography for lymph node staging in medium/high risk prostate cancer: A systematic review and meta-analysis

BACKGROUND

Lymph node staging of prostate cancer (PCa) is important for planning and monitoring of treatment. 18 F-prostate specific membrane antigen positron emission tomography/computerized tomography ( 18 F-PSMA PET/CT) has several advantages over 68 Ga-PSMA PET/CT, but its diagnostic value requires further investigation. This meta-analysis focused on establishing the diagnostic utility of 18 F-PSMA PET/CT for lymph node staging in medium/high-risk PCa.

METHODS

We searched the EMBASE, PubMed, Cochrane library, and Web of Science databases from inception to October 1, 2022. Prostate cancer, 18 F, lymph node, PSMA, and PET/CT were used as search terms and the language was limited to English. We additionally performed a manual search using the reference lists of key articles. Patients and study characteristics were extracted and the QUADAS-2 tool was employed to evaluate the quality of included studies. Sensitivity, specificity, the positive and negative likelihood ratio (PLR and NLR), diagnostic odds ratio (DOR), area under the curve (AUC), and 95% confidence interval (CI) were used to evaluate the diagnostic value of 18 F-PSMA PET/CT. Stata 17 software was employed for calculation and statistical analyses.

RESULTS

A total of eight diagnostic tests including 734 individual samples and 6346 lymph nodes were included in this meta-analysis. At the patient level, the results of each consolidated summary were as follows: sensitivity of 0.57 (95% CI 0.39-0.73), specificity of 0.95 (95% CI 0.92-0.97), PLR of 11.2 (95% CI 6.6-19.0), NLR of 0.46 (95% CI 0.31-0.68), DOR of 25 (95% CI 11-54), and AUC of 0.94 (95% CI 0.92-0.96). At the lesion level, the results of each consolidated summary were as follows: sensitivity of 0.40 (95% CI 0.21-0.62), specificity of 0.99 (95% CI 0.95-1.00), PLR of 40.0 (95% CI 9.1-176.3), NLR of 0.61 (95% CI 0.42-0.87), DOR of 66 (95% CI 14-311), and AUC of 0.86 (95% CI 0.83-0.89).

CONCLUSIONS

18 F-PSMA PET/CT showed moderate sensitivity but high specificity in lymph node staging of medium/high-risk PCa. The diagnostic efficacy was almost equivalent to that reported for 68 Ga-PSMA PET/CT.

REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), No. CRD42023391101.

Peritoneal Flap Following Lymph Node Dissection in Robotic Radical Prostatectomy: A Novel "Bunching" Technique

BACKGROUND

Pelvic lymph node dissection (PLND) is recommended while performing robot-assisted radical prostatectomy (RARP) for patients with localized intermediate or high-risk prostate cancer. However, symptomatic lymphoceles can occur after surgery, adding significant morbidity to patients. Our objective is to describe a novel Peritoneal Bladder Flap Bunching technique (PBFB) to reduce the risk of clinically significant lymphoceles in patients undergoing RARP and PLND.

METHODS

We evaluated 2267 patients who underwent RARP with PLND, dividing them into two groups: Group 1, comprising 567 patients who had the peritoneal flap (PBFB), and Group 2, comprising 1700 patients without the flap; propensity score matching carried out at a 1:3 ratio. Variables analyzed included estimated blood loss (EBL), operative time, postoperative complications, lymphocele formation, and the development of symptomatic lymphocele.

RESULTS

The two groups exhibited similar preoperative characteristics after matching. There was no statistically significant difference in the occurrence of lymphoceles between the flap group and the non-flap group, with rates of 24% and 20.9%, respectively (p = 0.14). However, none of the patients in the flap group (0%) developed symptomatic lymphoceles, whereas 2.2% of patients in the non-flap group experienced symptomatic lymphoceles (p = 0.01).

CONCLUSION

We have demonstrated a modified technique for a peritoneal flap (PBFB) with the initial elimination of postoperative symptomatic lymphoceles and promising short-term outcomes.

The Ability of the STAR-CAP Staging System to Prognosticate the Risk of Subsequent Therapies and Metastases After Initial Treatment of M0 Prostate Cancer

INTRODUCTION

The International Staging Collaboration for Prostate Cancer (STAR-CAP) has been proposed as a risk model for prostate cancer with superior prognostic power compared to the current staging system. This study aimed to evaluate the performance of STAR-CAP in predicting the risk of subsequent therapy after initial treatment and the risk of developing metastases.

PATIENTS AND METHODS

The study included 3425 men from an institutional observational registry with a median age of 64.9 years and a median follow-up time of 5.4 years. The primary endpoints were metastases and progression to additional therapy after initial therapy (radiation ± surgery). The risk of progression in the STAR-CAP group was estimated using a competing risk model (death).

RESULTS

The results showed that patients with STAR-CAP stages 1A-1C had a similar risk of requiring additional therapies and developing metastasis. Compared to stage IC, each stage from 2A to 3B incrementally increased the risk of subsequent therapy (hazard ratio (HR) 1.4-5.8, respectively) and metastases (HR 1.5-10.8, respectively). The 5-year probability of receiving subsequent therapy for a patient with stage IC was 8.6%, which increased from 11.4% to 37.4% for those with stages 2A to 3B. The 5-year probability of developing metastases for patients with stage IC was 1.5%, which increased from 2.2% to 8.2% for patients with stages 2A to 3B.

CONCLUSIONS

The probability of receiving subsequent therapy was higher for patients undergoing surgery, while radiation therapy patients were more likely to receive treatment with intensified multimodality therapies upfront.

Clinical parameters for the prediction of occult lymph node metastasis in patients with negative PSMA-PET

BACKGROUND

Depending on the risk of LN metastasis ePLND at RP is recommended. As ePLND has potential side effects, and diagnostics have improved substantially, our objective was to evaluate the performance of the Briganti 2019 nomogram in a contemporary cohort with preoperative negative PSMA-PET.

METHODS

Patients with intermediate- and high-risk prostate cancer (CaP), undergoing RP and ePND at our center with preoperative negative [68Ga]Ga-PSMA-11 PET were included. The Accuracy of the nomogram was assessed using ROC analysis. The association of clinical parameters with the presence of LN metastasis was assessed using logistic regression. Specimen of prostate and LNs in patients with false negative PSMA-PET were additionally stained for AR and PSMA expression and assessed by IHC.

RESULTS

The study included 108 patients, 28% intermediate- and 72% high-risk. Twelve patients harbored occult LN metastasis. Accuracy of the nomogram was 0.62. [68Ga]Ga-PSMA-11 PET showed a NPV of 89%. IHC showed expression of PSMA and AR in the primary and LN metastasis in all patients. On logistic regression analysis only DRE (OR 2.72; 95%CI 1.01-7.35; P = 0.05) and percentage of cores with significant CaP (OR 1.29; 95%CI 1.05-1.60; P = 0.02) showed a significant association with LN metastasis.

CONCLUSION

The currently used nomogram is suboptimal in detecting patients with occult LNM. While the cut-off value to perform ePLND can be increased slightly following a negative PSMA-PET scan, more accurate methods of identifying these patients are needed. Whether ePLND can have a therapeutic benefit, as opposed to a diagnostic only, needs to be re-evaluated in the PSMA-PET era.

Extended pelvic lymph node dissection in robot-assisted radical prostatectomy is an independent risk factor for major complications

The aim of this study is to evaluate the major postoperative complication rate after robot-assisted radical prostatectomy (RARP) and to identify related risk factors. A consecutive series of patients who underwent RARP between September 2016 and May 2021, with or without extended pelvic lymph node dissection (ePLND) were analyzed for postoperative complications that occurred within 30 days following surgery. Potential risk factors related to complications were identified by means of a multivariate logistic analysis. Electronic medical records were retrospectively reviewed for the occurrence of major complications (Clavien-Dindo grade III or higher) on a per patient level. A multivariate logistic regression with risk factors was performed to identify contributors to complications. In total, 1280 patients were included, of whom 79 (6.2%) experienced at least 1 major complication. Concomitant ePLND was performed in 609 (48%) of patients. The majority of all complications were likely related to the surgical procedure, with anastomotic leakage and lymphoceles being the most common. Upon multivariate analysis, performing ePLND remained the only significant risk factor for the occurrence of major complications (OR 2.26, p = 0.001). In contrast to robot-assisted radical prostatectomy alone, the combination with extended pelvic lymph node dissection (ePLND) has a substantial risk of serious complications. Since the ePLND is performed mainly for staging purpose, the clinical contribution of the ePLND has to be reconsidered with the present use of the PSMA-PET/CT.

Oncologic Outcome of the Extent of Pelvic Lymph Node Dissection During Radical Prostatectomy: A Systematic Review, Meta-analysis, and Network Analysis

CONTEXT

Some authors propose extended pelvic lymph node dissection (ePLND) to enhance diagnostic and therapeutic outcomes in patients with localized prostate cancer. However, recent evidence found no difference in biochemical recurrence (BCR).

OBJECTIVE

To stratify and analyze available evidence on ePLND and its impact on BCR in patients with localized prostate cancer.

EVIDENCE ACQUISITION

We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify studies up to November 2023. We identified original articles that presented statistical comparisons through Cox regressions reported as hazard ratio (HR) or survival curve data reported as Kaplan-Meier curve differences in BCR in patients undergoing radical prostatectomy and stratified by the extent of lymph node dissection for localized prostate cancer.

EVIDENCE SYNTHESIS

We identified 12 studies, with two being randomized controlled trials (RCTs). The RCTs showed no benefit of ePLND with an HR of 1.03 ([0.92, 1.14], p = 0.61). A combined analysis with the ten retrospective studies revealed a notable reduction in BCR with an HR of 0.68 ([0.52, 0.88], p = 0.003). A subgroup analysis based on the extent of dissection demonstrated that studies focusing on the more conservative extended template of dissection did not show significant BCR benefit (HR 0.97 [0.72, 1.32], p = 0.86). In contrast, dissections that expanded the anatomical extent showed decreased BCR (HR 0.56 [0.41, 0.75], p < 0.0001). A Bayesian network analysis highlights significant differences in BCR reduction between different dissection approaches, indicating the potential benefits of specific dissection templates.

CONCLUSIONS

Available literature on the extent of pelvic lymph node dissection needs to be improved in quality and varying definitions of the ePLND template. Dissection of the common iliac nodes may be beneficial.

PATIENT SUMMARY

There is a potential benefit in removing more lymph nodes during radical prostatectomy. However, more research is needed to determine whether this strategy benefits certain patient groups.

Prostate-Specific Membrane Antigen-Targeted Radioguided Pelvic Lymph Node Dissection in Newly Diagnosed Prostate Cancer Patients with a Suspicion of Locoregional Lymph Node Metastases: The DETECT Trial

Prostate-specific membrane antigen (PSMA)-targeted radioguided surgery (RGS) aims to optimize the peroperative detection and removal of PSMA-avid lymph node (LN) metastases (LNMs) and has been described in patients with recurrent prostate cancer (PCa). In newly diagnosed PCa patients undergoing pelvic LN dissections, PSMA RGS could guide the urologist toward PSMA-expressing LNMs as identified on preoperative 18F-PSMA PET/CT imaging. The objective was to evaluate the safety and feasibility of 111In-PSMA RGS in primary PCa patients with one or more suggestive LNs on preoperative 18F-PSMA PET/CT. Methods: This prospective, phase I/II study included 20 newly diagnosed PCa patients with at least 1 suggestive LN on preoperative 18F-PSMA PET/CT. PSMA RGS was performed 24 h after 111In-PSMA-I&T administration, and postoperative 18F-PSMA PET/CT was performed to verify successful removal of the suggestive lesions. The primary endpoint was determination of the safety and feasibility of 111In-PSMA RGS. Safety was assessed by monitoring adverse events. Feasibility was described as the possibility to peroperatively detect suggestive LNs as identified on preoperative imaging. Secondary outcomes included the accuracy of 111In-PSMA RGS compared with histopathology, tumor- and lesion-to-background ratios, and biochemical recurrence. Results: No tracer-related adverse events were reported. In 20 patients, 43 of 49 (88%) 18F-PSMA PET-suggestive lesions were successfully removed. 111In-PSMA RGS facilitated peroperative identification and resection of 29 of 49 (59%) RGS-target lesions, of which 28 (97%) contained LNMs. Another 14 of 49 (29%) resected LNs were not detected with 111In-PSMA RGS, of which 2 contained metastases. Conclusion: 111In-PSMA RGS is a safe and feasible procedure that allows peroperative detection of 18F-PSMA PET/CT-suggestive lesions in newly diagnosed PCa patients. The use of a radioactive PSMA tracer and a detection device (γ-probe) during surgery helps in identifying LNs that were suggestive of PCa metastases on the 18F-PSMA PET/CT before surgery and thus may improve the peroperative identification and removal of these LNs.

A comparative analysis of perioperative complications and biochemical recurrence between standard and extended pelvic lymph node dissection in prostate cancer patients undergoing radical prostatectomy: a systematic review and meta-analysis

INTRODUCTION

Pelvic lymph node dissection (PLND) is commonly performed during radical prostatectomy (RP) for prostate cancer staging. This study aimed to comprehensively analyze existing evidence compare perioperative complications associated with standard (sPLND) versus extended PLND templates (ePLND) in RP patients.

METHODS

A meta-analysis of prospective studies on PLND complications was conducted. Systematic searches were performed on Web of Science, Pubmed, Embase, and the Cochrane Library until May 2023. Risk ratios (RRs) were estimated using random-effects models in the meta-analysis. The statistical analysis of the data was carried out using Review Manager software.

RESULTS

Nine studies, including three randomized clinical trial and six prospective studies, with a total of 4962 patients were analyzed. The meta-analysis revealed that patients undergoing ePLND had a higher risk of partial perioperative complications, such as lymphedema ( I2 =28%; RR 0.05; 95% CI: 0.01-0.27; P <0.001) and urinary retention ( I2 =0%; RR 0.30; 95% CI: 0.09-0.94; P =0.04) compared to those undergoing sPLND. However, there were no significant difference was observed in pelvic hematoma ( I2 =0%; RR 1.65; 95% CI: 0.44-6.17; P =0.46), thromboembolic ( I2 =57%; RR 0.91; 95% CI: 0.35-2.38; P =0.85), ureteral injury ( I2 =33%; RR 0.28; 95% CI: 0.05-1.52; P =0.14), intraoperative bowel injury ( I2 =0%; RR 0.87; 95% CI: 0.14-5.27; P =0.88), and lymphocele ( I2 =0%; RR 1.58; 95% CI: 0.54-4.60; P =0.40) between sPLND and ePLND. Additionally, no significant difference was observed in overall perioperative complications ( I2 =85%; RR 0.68; 95% CI: 0.40-1.16; P =0.16). Furthermore, ePLND did not significantly reduce biochemical recurrence ( I2 =68%; RR 0.59; 95% CI: 0.28-1.24; P =0.16) of prostate cancer.

CONCLUSION

This analysis found no significant differences in overall perioperative complications or biochemical recurrence between sPLND and ePLND, but ePLND may offer enhanced diagnostic advantages by increasing the detection rate of lymph node metastasis.

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.

Association of Lymphovascular Invasion with Lymph Node Metastases in Prostate Cancer-Lateralization Concept

BACKGROUND

Lymphovascular invasion (LVI) is a vital but often overlooked prognostic factor in prostate cancer. As debates on lymphadenectomy's overtreatment emerge, understanding LVI laterality gains importance. This study pioneers the investigation into PCa, aiming to uncover patterns that could influence tailored surgical strategies in the future.

METHODS

Data from 96 patients with both LVI and lymph node invasion (LNI) were retrospectively analyzed. All participants underwent radical prostatectomy (RP) with modified-extended pelvic lymph node dissection (mePLND). All specimens underwent histopathological examination. The assessment of LVI was conducted separately for the right and left lobes of the prostate. Associations within subgroups were assessed using U-Mann-Whitney and Kruskal-Wallis tests, as well as Kendall's tau-b coefficient, yielding p-values and odds ratios (ORs).

RESULTS

Out of the 96 patients, 61 (63.5%) exhibited exclusive left-sided lymphovascular invasion (LVI), 24 (25.0%) had exclusive right-sided LVI, and 11 (11.5%) showed bilateral LVI. Regarding nodal involvement, 23 patients (24.0%) had LNI solely on the left, 25 (26.0%) exclusively on the right, and 48 (50.0%) on both sides. A significant correlation was observed between lateralized LVI and lateralized LNI (p < 0.001), particularly in patients with right-sided LVI only. LN-positive patients with left-sided LVI tended to have higher pT stages (p = 0.047) and increased odds ratios (OR) of bilateral LNI (OR = 2.795; 95% confidence interval [CI]: 1.231-6.348) compared to those with exclusive right-sided LVI (OR = 0.692; 95% CI: 0.525-0.913).

CONCLUSIONS

Unilateral LVI correlates with ipsilateral LNI in PCa patients with positive LNs, notably in cases of exclusively right-sided LVI. Left-sided LVI associates with higher pT stages and a higher percentage of bilateral LNI cases.

A non-invasive 25-Gene PLNM-Score urine test for detection of prostate cancer pelvic lymph node metastasis

BACKGROUND

Prostate cancer patients with pelvic lymph node metastasis (PLNM) have poor prognosis. Based on EAU guidelines, patients with >5% risk of PLNM by nomograms often receive pelvic lymph node dissection (PLND) during prostatectomy. However, nomograms have limited accuracy, so large numbers of false positive patients receive unnecessary surgery with potentially serious side effects. It is important to accurately identify PLNM, yet current tests, including imaging tools are inaccurate. Therefore, we intended to develop a gene expression-based algorithm for detecting PLNM.

METHODS

An advanced random forest machine learning algorithm screening was conducted to develop a classifier for identifying PLNM using urine samples collected from a multi-center retrospective cohort (n = 413) as training set and validated in an independent multi-center prospective cohort (n = 243). Univariate and multivariate discriminant analyses were performed to measure the ability of the algorithm classifier to detect PLNM and compare it with the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram score.

RESULTS

An algorithm named 25 G PLNM-Score was developed and found to accurately distinguish PLNM and non-PLNM with AUC of 0.93 (95% CI: 0.85-1.01) and 0.93 (95% CI: 0.87-0.99) in the retrospective and prospective urine cohorts respectively. Kaplan-Meier plots showed large and significant difference in biochemical recurrence-free survival and distant metastasis-free survival in the patients stratified by the 25 G PLNM-Score (log rank P < 0.001 and P < 0.0001, respectively). It spared 96% and 80% of unnecessary PLND with only 0.51% and 1% of PLNM missing in the retrospective and prospective cohorts respectively. In contrast, the MSKCC score only spared 15% of PLND with 0% of PLNM missing.

CONCLUSIONS

The novel 25 G PLNM-Score is the first highly accurate and non-invasive machine learning algorithm-based urine test to identify PLNM before PLND, with potential clinical benefits of avoiding unnecessary PLND and improving treatment decision-making.

The efficacy of peritoneal flap fixation on symptomatic lymphocele formation following robotic-assisted laparoscopic radical prostatectomy with pelvic lymph node dissection: a systematic review and meta-analysis

BACKGROUND

Pelvic lymphocele is the most common complication after robot-assisted radical prostatectomy (RARP) with pelvic lymph node dissection (PLND), of which symptomatic lymphocele (sLC) ranges up to 10% and is associated with poorer perioperative outcomes. Peritoneal flap fixation (PFF) is a promising intraoperative modification to reduce sLC formation but the clinical evidence failed to reach consistency.

MATERIALS AND METHODS

Randomized and nonrandomized comparative studies comparing postoperative sLC occurrence with or without PFF after RARP with PLND were identified through a systematic literature search via MEDLINE/PubMed, Embase, Web of Science, and CENTRAL up to July 2023. Outcome data of sLC occurrence (primary) and major perioperative events (secondary) were extracted. Mean difference and risk ratio with 95% CI were synthesized as appropriate for each outcome to determine the cumulative effect size.

RESULTS

Five RCTs and five observatory studies involving 3177 patients were finally included in the qualitative and quantitative analysis. PFF implementation significantly reduced the occurrence of sLC (RR 0.35, 95% CI: 0.24-0.50), and the specific lymphocele-related symptoms, without compromised perioperative outcomes including blood loss, operative time, and major nonlymphocele complications. The strength of the evidence was enhanced by the low risk of bias and low inter-study heterogeneity of the eligible RCTs.

CONCLUSION

PFF warrants routine implementation after RARP with PLND to prevent or reduce postoperative sLC formation.

Standardization of robot-assisted pelvic lymph node dissection-Development of a common understanding of regional anatomy and surgical technique based on cross-disciplinary discussion among colorectal surgery, urology, and gynecology

BACKGROUND

Pelvic lymph node dissection is a procedure performed in gastroenterological surgery, urology, and gynecology. However, due to discrepancies in the understanding of pelvic anatomy among these departments, cross-disciplinary discussions have not been easy. Recently, with the rapid spread of robotic surgery, the importance of visual information in understanding pelvic anatomy has become even more significant. In this project, we attempted to clarify a shared understanding of pelvic anatomy through cross-disciplinary discussions.

METHOD

From May 2020 to November 2021, a total of 11 discussions were held entirely online with 5 colorectal surgery specialists, 4 urologists, and 4 gynecologists. The discussions focused on evidence from each specialty and surgical videos, aiming to create a universally understandable pelvic anatomical illustration.

RESULTS

The common area of dissection recognized across the three departments was identified as the obturator lymph nodes. A dynamic illustration of pelvic anatomy was created. In addition to a bird's-eye view of the pelvis, a pelvic half view was developed to enhance understanding of the deeper pelvic anatomy. The following insights were incorporated into the illustration: (1) the cardinal ligament in gynecology partly overlaps with the vesicohypogastric fascia in colorectal surgery; (2) the obturator lymph nodes continue cephalad into the fossa of Marcille in urology; and (3) the deep uterine vein in gynecology corresponds to the inferior vesical vein in colorectal surgery.

CONCLUSION

Based on the dynamic illustration of pelvic anatomy from cross-disciplinary discussions, we anticipate advancements in pelvic lymph node dissection aiming for curative and safe outcomes.

The diagnostic accuracy of 68 Ga-PSMA-PET/CT in primary staging of patients with high-risk nonmetastatic prostate cancer treated with radical prostatectomy: A single-center cohort analysis

BACKGROUND

68 Ga-prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) is a recommended imaging modality for patients with recurrent prostate cancer (PCa). Its routine implementation before radical prostatectomy (RP) may allow avoiding undertreatment. We aimed to analyze the diagnostic accuracy of 68 Ga-PSMA-PET/CT for pelvic lymph node metastases in a large cohort of patients treated with RP and extended pelvic lymph node dissection (ePLND) for high-risk PCa.

METHODS

This is a retrospective analysis of an institutional database of patients who underwent 68 Ga-PSMA-PET/CT before RP and ePLND for high-risk PCa. The diagnostic estimates of 68 Ga-PSMA-PET/CT with 95% confidence intervals (CIs) for lymph node involvement were calculated.

RESULTS

We included 165 high-risk PCa patients. The median PSA value was 24.5 ng/mL (range: 6.7-185) and all the patients had biopsy Grade Group 4-5. In total, 46 (28%) of patients had clinical lymph node involvement at 68 Ga-PSMA-PET/CT. A mean number of resected lymph nodes per patient was 22 (range: 15-45) and 149 (4.2%) of all resected nodes were positive for lymph node metastasis at final pathology. The diagnostic estimates for the detection of pN+ disease at RP were as follows: sensitivity 63% (95% CI: 51-75), specificity 97% (95% CI: 91-99), positive predictive value 94% (95% CI: 82-99), and negative predictive value 79% (95% CI: 70-86). The total accuracy of PSMA-PET was 83% (95% CI: 76-88).

CONCLUSION

Our analyses support high specificity and positive predictive value of pretreatment 68 Ga-PSMA PET/CT for the detection of pelvic lymph node metastasis in patients treated with RP for high-risk PCa. While a positive finding should be considered as robust indicator for clinical decision-making, a negative result cannot reliably rule out the presence of lymph node involvement in high-risk PCa; there is a need for advanced risk stratification in those patients.

Surgical Management and Considerations for Patients with Localized High-Risk Prostate Cancer

OPINION STATEMENT

Localized high-risk (HR) prostate cancer (PCa) is a heterogenous disease state with a wide range of presentations and outcomes. Historically, non-surgical management with radiotherapy and androgen deprivation therapy was the treatment option of choice. However, surgical resection with radical prostatectomy (RP) and pelvic lymph node dissection (PLND) is increasingly utilized as a primary treatment modality for patients with HRPCa. Recent studies have demonstrated that surgery is an equivalent treatment option in select patients with the potential to avoid the side effects from androgen deprivation therapy and radiotherapy combined. Advances in imaging techniques and biomarkers have also improved staging and patient selection for surgical resection. Advances in robotic surgical technology grant surgeons various techniques to perform RP, even in patients with HR disease, which can reduce the morbidity of the procedure without sacrificing oncologic outcomes. Clinical trials are not only being performed to assess the safety and oncologic outcomes of these surgical techniques, but to also evaluate the role of surgical resection as a part of a multimodal treatment plan. Further research is needed to determine the ideal role of surgery to potentially provide a more personalized and tailored treatment plan for patients with localized HR PCa.

De-Escalation of Therapy for Prostate Cancer

Prostate cancer (PCa) is the second most commonly diagnosed cancer in men with around 1.4 million new cases every year. In patients with localized disease, management options include active surveillance (AS), radical prostatectomy (RP; with or without pelvic lymph node dissection), or radiotherapy to the prostate (with or without pelvic irradiation) with or without hormonotherapy. In advanced disease, treatment options include systemic treatment(s) and/or treatment to primary tumour and/or metastasis-directed therapies (MDTs). Specifically, in advanced stage, the current trend is earlier intensification of treatment such as dual or triple combination systemic treatments or adding treatment to primary and MDT to systemic treatment. However, earlier treatment intensification comes with the cost of increased morbidity and mortality resulting from drug-/treatment-related side effects. The main goal is and should be to provide the best possible care and oncologic outcomes with minimum possible side effects. This chapter will explore emerging possibilities to de-escalate treatment in PCa driven by enhanced insights into disease biology and the natural course of PCa such as AS in intermediate-risk disease or salvage versus adjuvant radiotherapy in post-RP patients. Considerations arising from advancements in PCa imaging and technological advancements in surgical and radiation therapy techniques including omitting pelvic lymph node dissection in the era of prostate-specific membrane antigen positron emitting tomography, the potential of MDT to delay/omit systemic treatment in metachronous oligorecurrence, and the efficacy of hypofractionation schemes compared with conventional fractionated radiotherapy will be discussed.

Lymph nodes: at the intersection of cancer treatment and progression

Metastasis to lymph nodes (LNs) is a common feature of disease progression in most solid organ malignancies. Consequently, LN biopsy and lymphadenectomy are common clinical practices, not only because of their diagnostic utility but also as a means of deterring further metastatic spread. LN metastases have the potential to seed additional tissues and can induce metastatic tolerance, a process by which tumor-specific immune tolerance in LNs promotes further disease progression. Nonetheless, phylogenetic studies have revealed that distant metastases are not necessarily derived from nodal metastases. Furthermore, immunotherapy efficacy is increasingly being attributed to initiation of systemic immune responses within LNs. We argue that lymphadenectomy and nodal irradiation should be approached with caution, particularly in patients receiving immunotherapy.

Identification of the Optimal Candidates for Nodal Staging with Extended Pelvic Lymph Node Dissection Among Prostate Cancer Patients Who Underwent Preoperative Prostate-specific Membrane Antigen Positron Emission Tomography. External Validation of the Memorial Sloan Kettering Cancer Center and Briganti Nomograms and Development of a Novel Tool

BACKGROUND

Although the therapeutic role of extended pelvic lymph node dissection (ePLND) in patients with prostate cancer (PCa) is still under debate, this procedure is recommended for staging purposes in selected cases. Nomograms for predicting lymph node invasion (LNI) do not account for prostate-specific membrane antigen (PSMA) positron emission tomography (PET) imaging, which is characterized by a high negative predictive value for nodal metastases.

OBJECTIVE

To externally validate models predicting LNI in patients with miN0M0 PCa at PSMA PET and to develop a novel tool in this setting.

DESIGN, SETTING, AND PARTICIPANTS

Overall, 458 patients with miN0M0 disease undergoing radical prostatectomy (RP) and ePLND at 12 centers between 2017 and 2022 were identified.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

Available tools were externally validated using calibration plots, the area under the receiver operating characteristic curve (AUC), and decision curve analyses to assess calibration, discrimination, and the net benefit. A novel coefficient-based model was developed, internally validated, and compared with available tools.

RESULTS AND LIMITATIONS

Overall, 53 patients (12%) had LNI. The AUC was 69% for the Briganti 2012, 64% for the Briganti 2017, 73% for the Briganti 2019, and 66% for the Memorial Sloan Kettering Cancer Center nomogram. Multiparametric magnetic resonance imaging stage, biopsy grade group 5, the diameter of the index lesion, and the percentage of positive cores at systematic biopsy were independent predictors of LNI (all p ≤ 0.04). Internal cross-validation confirmed a coefficient-based model with AUC of 78%, better calibration, and a higher net benefit in comparison to the other nomograms assessed. Use of a 5% cutoff would have spared 47% ePLND procedures (vs 13% for the Briganti 2019 nomogram) at the cost of missing only 2.1% LNI cases . The lack of central review of imaging and pathology represents the main limitation.

CONCLUSIONS

Tools for predicting LNI are associated with suboptimal performance for men with miN0M0 PCa. We propose a novel model for predicting LNI that outperforms available tools in this population.

PATIENT SUMMARY

Tools currently used to predict lymph node invasion (LNI) in prostate cancer are not optimal for men with negative node findings on PET (positron emission tomography) scans, leading to a high number of unnecessary extended pelvic lymph node dissection (ePLND) procedures. A novel tool should be used in clinical practice to identify candidates for ePLND to reduce the risk of unnecessary procedures without missing LNI cases.

Personalised indocyanine-guided lymphadenectomy for prostate cancer: a randomised clinical trial

OBJECTIVES

To study the safety and efficacy of a personalised indocyanine-guided pelvic lymph node dissection (PLND) against extended PLND (ePLND) during radical prostatectomy (RP).

PATIENTS AND METHODS

Patients who were candidates for RP and lymphadenectomy, with intermediate- or high-risk prostate cancer (PCa) according to the National Comprehensive Cancer Network guidelines, were enrolled in this randomised clinical trial. Randomisation was made 1:1 to indocyanine green (ICG)-PLND (only ICG-stained LNs) or ePLND (obturator fossa, external, internal, and common iliac and presacral LNs). The primary endpoint was the complication rate within 3 months after RP. Secondary endpoints included: rate of major complications (Clavien-Dindo Grade III-IV), time to drainage removal, length of stay, percentage of patients classified as pN1, number of LNs removed, number of metastatic LNs, rate of patients with undetectable prostate-specific antigen (PSA), biochemical recurrence (BCR)-free survival, and rate of patients with androgen-deprivation therapy at 24 months.

RESULTS

A total of 108 patients were included with a median follow-up of 16 months. In all, 54 were randomised to ICG-PLND and 54 to ePLND. The postoperative complication rate was higher in the ePLND (70%) vs the ICG-PLND group (32%) (P < 0.001). Differences between major complications in both groups were not statically significant (P = 0.7). The pN1 detection rate was higher in the ICG-PLND group (28%) vs the ePLND group (22%); however, this difference was not statistically significant (P = 0.7). The rate of undetectable PSA at 12 months was 83% in the ICG-PLND vs 76% in the ePLND group, which was not statistically significant. Additionally, there were no statistically significant differences in BCR-free survival between groups at the end of the analysis.

CONCLUSIONS

Personalised ICG-guided PLND is a promising technique to stage patients with intermediate- and high-risk PCa properly. It has shown a lower complication rate than ePLND with similar oncological outcomes at short-term follow-up.

Extraperitoneal robot-assisted radical prostatectomy with the Hugo™ RAS system: initial experience of a tertiary center with a high background in extraperitoneal laparoscopy surgery

PURPOSE

The Hugo™ RAS system is a novel robotic platform with innovative features. However, there are currently no available data on extraperitoneal robot-assisted radical prostatectomy (RARP) performed using this system. The objective of this study is to describe the surgical setup and assess the safety and feasibility of the extraperitoneal approach in robotic radical prostatectomy with the Hugo™ RAS system.

METHODS

Sixteen consecutive patients diagnosed with localized prostate cancer underwent extraperitoneal RARP ± lymph node dissection at our institution, between March and May 2023. All RARP procedures were performed extraperitoneal with a modular four-arm configuration. The focus was to describe the operative room setup, trocar placement, tilt and docking angles and evaluate the safety and feasibility of this approach with this robotic platform. Secondary outcomes recorded included, total operative time, console time, estimated bleeding, intra- and postoperative complications, and length of stay after surgery. A descriptive analysis was conducted.

RESULTS

We report on the first sixteen cases of extraperitoneal robot-assisted radical prostatectomy performed with the new Hugo™ RAS system. All procedures were completed, without the need for conversion or placement of additional ports. No intraoperative complications or major technical failures that would prevent the completion of surgery were recorded. The median operative time was 211 min (IQR 180-277), and the median console time was 152 min (IQR 119-196). The mean docking time was 4.6 min (IQR 4.1-5.2). The median estimated blood loss and the median time to remove the vesical catheter were 200 mL (IQR 150-400) and 8 days (IQR 7-8), respectively. The median length of stay was 2 days (IQR 2-2). Only one minor complication was registered in the first 30 days.

CONCLUSION

This study provides evidence of the safety and feasibility of the extraperitoneal approach in RARP with the Hugo™ RAS system. The description of the surgical setup in terms of trocar placement, arm-cart disposition, tilt and docking angles offers valuable information for surgeons interested in adopting this surgical approach with the Hugo™ RAS platform.

The impact of previous inguinal mesh hernioplasty on oncological and patient-reported outcomes following radical prostatectomy

BACKGROUND

The impact of previous inguinal mesh hernioplasty (MH) with non-resorbable mesh prostheses on surgical performance of radical prostatectomy (RP) has been controversially discussed, with unknown impact of MH on oncologic outcomes and health-related quality of life (HRQOL) following RP. We therefore aimed to assess the influence of previous MH on metastasis-free survival (MFS), biochemical recurrence-free survival (BRFS), and HRQOL following RP.

METHODS

We identified 344 patients with previous MH prior RP within our prospectively assessed institutional database of 6275 patients treated with RP for PC (2008-2019). A 1:3 propensity-score matched analysis of 1345 men (n = 319 previous MH, n = 1026 no previous MH) was conducted. Primary endpoint was MFS and secondary endpoints were BRFS and HRQOL (based on EORTC QLQ-C30). Binary logistic regression, Kaplan-Meier, and Cox regression models tested the effect of previous MH on MFS, BRFS, and HRQOL (p < 0.05).

RESULTS

Median follow-up was 47 months. Patients with previous MH had significantly lower 5-year MFS (72% vs. 85%, p < 0.001) and 5-year BRFS estimates (43% vs. 57%, p < 0.001). In multivariate analysis, previous MH was confirmed as an independent predictor for impaired MFS (hazard ratio [HR]: 3.772, 95% CI 1.12-12.64, p = 0.031) and BRFS (HR: 1.862, 95% CI: 1.22-2.85, p = 0.004). These results held true if stratified for surgical approach or limited to patients with successful PLND. We found significantly shorter median time to continence recovery for patients without previous MH (p = 0.001) without significant differences in total continence recovery rates, erectile function recovery, and HRQOL.

CONCLUSIONS

Our findings show an impaired oncologic outcome for patients with previous MH following RP with no significant differences regarding continence recovery, erectile function recovery, and general HRQOL.

Development and External Validation of a Machine Learning Model for Prediction of Lymph Node Metastasis in Patients with Prostate Cancer

BACKGROUND

Pelvic lymph node dissection (PLND) is the gold standard for diagnosis of lymph node involvement (LNI) in patients with prostate cancer. The Roach formula, Memorial Sloan Kettering Cancer Center (MSKCC) calculator, and Briganti 2012 nomogram are elegant and simple traditional tools used to estimate the risk of LNI and select patients for PLND.

OBJECTIVE

To determine whether machine learning (ML) can improve patient selection and outperform currently available tools for predicting LNI using similar readily available clinicopathologic variables.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective data for patients treated with surgery and PLND between 1990 and 2020 in two academic institutions were used.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We trained three models (two logistic regression models and one gradient-boosted trees-based model [XGBoost]) on data provided from one institution (n = 20267) with age, prostate-specific antigen (PSA) levels, clinical T stage, percentage positive cores, and Gleason scores as inputs. We externally validated these models using data from another institution (n = 1322) and compared their performance to that of the traditional models using the area under the receiver operating characteristic curve (AUC), calibration, and decision curve analysis (DCA).

RESULTS AND LIMITATIONS

LNI was present in 2563 patients (11.9%) overall, and in 119 patients (9%) in the validation data set. XGBoost had the best performance among all the models. On external validation, its AUC outperformed that of the Roach formula by 0.08 (95% confidence interval [CI] 0.042-0.12), the MSKCC nomogram by 0.05 (95% CI 0.016-0.070), and the Briganti nomogram by 0.03 (95% CI 0.0092-0.051; all p < 0.05). It also had better calibration and clinical utility in terms of net benefit on DCA across relevant clinical thresholds. The main limitation of the study is its retrospective design.

CONCLUSIONS

Taking all measures of performance together, ML using standard clinicopathologic variables outperforms traditional tools in predicting LNI.

PATIENT SUMMARY

Determining the risk of cancer spread to the lymph nodes in patients with prostate cancer allows surgeons to perform lymph node dissection only in patients who need it and avoid the side effects of the procedure in those who do not. In this study, we used machine learning to develop a new calculator to predict the risk of lymph node involvement that outperformed traditional tools currently used by oncologists.