External validation of the updated Briganti nomogram to predict lymph node invasion in prostate cancer patients undergoing extended lymph node dissection

Complications of Extended Pelvic Lymph Node Dissection in Patients Undergoing Minimally Invasive Radical Prostatectomy: Analysis and Risk Factors

Background

The knowledge of risk factors and complications related to extended pelvic lymph node dissection (ePLND) during radical prostatectomy can help selecting patients who will benefit the most with lymph node dissection concomitant to radical prostatectomy.

Materials and Methods

Retrospective cohort evaluating 135 patients with PC, with a high risk for lymph node metastasis, submitted to ePLND by a single surgeon between 2013 and 2019, performed either by the laparoscopic or laparoscopic robot-assisted approach. Data related to complications were properly recorded using the Martin's criteria and were classified by the Satava and Clavien–Dindo–Strasberg methods. Logistic regression was used to determine predictors of complications related to ePLND.

Results

The mean number of lymph nodes removed was 10.2 ± 4.9, and in 28.2%, they were positive for metastasis. There were five intraoperative complications (4%), all in patients operated by laparoscopic approach. There were nine severe postoperative complications (7.3%), four of which occurred after postoperative day 30. Three patients (2.4%) had thromboembolic complications and five patients (4.0%) had lymphocele that required treatment. There was a correlation between the American Society of Anesthesiologists (ASA) physical status classification and postoperative complications (p=0.06), but it was not possible to identify statistically significant predictors.

Conclusion

ePLND during radical prostatectomy has a low rate of intraoperative complications and may change prostate cancer staging. Postoperative complications, especially venous thromboembolism and lymphocele, need to be monitored even in the late postoperative period.

From past to future: Bibliometric analysis of global research productivity on nomogram (2000-2021)

Background

Nomogram, a visual clinical predictive model, provides a scientific basis for clinical decision making. Herein, we investigated 20 years of nomogram research responses, focusing on current and future trends and analytical challenges.

Methods

We mined data of scientific literature from the Core Collection of Web of Science, searching for the original articles with title "Nomogram^*/Parton Table^*/Parton Nomogram^*", published within January 1st, 2000 to December 30th, 2021. Data records were validated using HistCite Version and analyzed with a transformable statistical method, the Bibliometrix 3.0 package of R Studio.

Results

In total, 4,176 original articles written by 19,158 authors were included from 915 sources. Annually, Nomogram publications are continually produced, which have rapidly grown since 2018. China published the most articles; however, its total citations ranked second after the United States. Both total citations and average article citations in the United States rank first globally, and a high degree of cooperation exists between countries. Frontiers in Oncology published the most papers (238); this number has grown rapidly since 2019. Journal of Urology had the highest H-index, with an average increase in publications over the past 20 years. Most research topics were tumor-related, among which tumor risk prediction and prognostic evaluation were the main contents. Research on prognostic assessment is more published and advanced, while risk prediction and diagnosis have good developmental prospects. Furthermore, nomogram of the urinary system has been highly developed. Following advancements in nomogram modeling, it has recently been applied to non-oncological subjects.

Conclusion

This bibliometric analysis provides a comprehensive overview of the current nomogram status, which could enable better understanding of its development over the years, and provide global researchers a comprehensive analysis and structured information to help identify hot spots and gaps in future research.

Pelvic lymph node dissection in high-risk prostate cancer

INTRODUCTION

The therapeutic role of pelvic lymph node dissection (PLND) in prostate cancer (PCa) is unknown due to absence of randomized trials.

OBJECTIVE

to present a critical review on the therapeutic benefits of PLND in high risk localized PCa patients.

MATERIALS AND METHODS

A search of the literature on PLND was performed using PubMed, Cochrane, and Medline database. Articles obtained regarding diagnostic imaging and sentinel lymph node dissection, PLND extension, impact of PLND on survival, PLND in node positive "only" disease and PLND surgical risks were critically reviewed.

RESULTS

High-risk PCa commonly develops metastases. In these patients, the possibility of presenting lymph node disease is high. Thus, extended PLND during radical prostatectomy may be recommended in selected patients with localized high-risk PCa for both accurate staging and therapeutic intent. Although recent advances in detecting patients with lymph node involvement (LNI) with novel imaging and sentinel node dissection, extended PLND continues to be the most accurate method to stage lymph node disease, which may be related to the number of nodes removed. However, extended PLND increases surgical time, with potential impact on perioperative complications, hospital length of stay, rehospitalization and healthcare costs. Controversy persists on its therapeutic benefit, particularly in patients with high node burden.

CONCLUSION

The impact of PLND on biochemical recurrence and PCa survival is unclear yet. Selection of patients may benefit from extended PLND but the challenge remains to identify them accurately. Only prospective randomized study would answer the precise role of PLND in high-risk pelvis confined PCa patients.

External Validation of the Briganti Nomogram to Predict Lymph Node Invasion in Prostate Cancer-Setting a New Threshold Value

(1) Introduction: The study aimed to test and validate the performance of the 2012 Briganti nomogram as a predictor for pelvic lymph node invasion (LNI) in men who underwent radical prostatectomy (RP) with extended pelvic lymph node dissection (PLND) to examine their performance and to analyse the therapeutic impact of using a different nomogram cut-off. (2) Material and Methods: The study group consisted of 222 men with clinically localized prostate cancer (PCa) who underwent RP with ePLND between 01/2012 and 10/2018. Measurements included: preoperative PSA, clinical stage (CS), primary and secondary biopsy Gleason pattern, and the percentage of positive cores. The area under the curve (AUC) of the receiver operator characteristic analysis was appointed to quantify the accuracy of the primary nomogram model to predict LNI. The extent of estimation associated with the use of this model was graphically depicted using calibration plots. (3) Results: The median number of removed lymph nodes was 16 (IQR 12–21). A total of 53 of 222 patients (23.9%) had LNI. Preoperative clinical and biopsy characteristics differed significantly (all p < 0.005) between men with and without LNI. A nomogram-derived cut-off of 7% could lead to a reduction of 43% (95/222) of lymph node dissection while omitting 19% (10/53) of patients with LNI. The sensitivity, specificity, and negative predictive value associated with the 7% cut-off were 81.1%, 50.3%, and 96.3%, respectively. (4) Conclusions: The analysed nomogram demonstrated high accuracy for LNI prediction. A nomogram-derived cut-off of 7% confirmed good performance characteristics within the first external validation cohort from Poland.

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

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

A narrative review of pelvic lymph node dissection in prostate cancer

Pelvic lymph node dissection (PLND) is an important component in the staging and prognostication of prostate cancer. We performed a narrative review to assess the literature surrounding PLND: (I) the current guideline recommendations and contemporary utilization, (II) the calculation of patient-specific risk to perform PLND using available nomograms, (III) to review the extent of dissection, and its associated outcomes and complications. Due to the improved lymph node yield, better staging, and theoretical improvement in the control of micro-metastatic disease, guidelines have supported the use of (extended-) PLND in patients deemed to be at intermediate or high risk of lymph node involvement (often at a threshold of 5% on modern risk nomograms). However, in practice, real-world utilization of PLND varies considerably due to multiple reasons. Conflicting evidence persists with no clear oncological benefit to PLND, and a small, but important, risk of morbidity. Complications are rare, but include lymphoceles; thromboembolic events; and more rarely, obturator nerve, vascular, and ureteric injury. Furthermore, changing disease incidence and stage migration in the context of earlier detection overall have led to a decreased risk of nodal disease. The trade-offs between the benefits, harms, and risk tolerance/threshold must be carefully considered between each patient and their clinician.

Sensitivity and specificity of Briganti nomogram in Turkish patients undergoing radical prostatectomy and pelvic lymph node dissection

AIM

To investigate the accuracy of Briganti nomogram in patients who underwent Pelvic lymph node dissection (PLND).

METHODS

Hundred and sixty-five patients who underwent radical prostatectomy and PLND between 2012 and 2018 in our clinics were included, and their data were retrospectively screened.

RESULTS

The mean age of patients was 63.6 ± 5.8 (range: 49-76) years. Hundred and thirty-five (81.8%) patients had a Briganti score of <5, whereas 30 (18.2%) had a Briganti score of ≥5. The preoperative T-PSA levels, biopsy grades and the incidence of T2b and T2c stages in patients with a Briganti score of ≥5 was significantly higher than that in patients with a Briganti score of <5 (p: .026; p: .000; p: .001, respectively). The incidence of lymph node positivity in patients with a Briganti score of ≥5 (76.7%) was significantly higher than that in patients with a Briganti score of <5 (25.2%) (p: .000). The sensitivity of the Briganti score to detect lymph node positivity was 40.35%, specificity was 93.52%, positive predictive value was 76.67% and the negative predictive value was 74.81%. The accuracy of the test was 75.15%.

CONCLUSION

Nomograms provide useful information regarding prostate cancer. Risk estimates should be carefully considered, and treatment decisions should be given with a patient-specific approach.

External evaluation of the Briganti nomogram to predict lymph node metastases in intermediate-risk prostate cancer patients

PURPOSE

The Briganti nomogram can be used with a threshold of 5% to decide when to offer lymph node dissection during radical prostatectomy. The objective of the study was to assess the accuracy of the Briganti nomogram on intermediate-risk prostate cancer patients managed in a single academic department.

METHODS

We retrospectively reviewed the files of all patients managed by radical prostatectomy (RP) and bilateral pelvic lymph node dissection (BPLND) in our center between 2005 and 2017. The overall accuracy of the model in predicting metastatic lymph node disease was quantified by the construction of a receiver-operator characteristic (ROC) curve. A calibration plot was drawn to represent the relationship between the predicted and observed frequencies.

RESULTS

We included 285 patients, among whom 175 (61.4%) were classified as intermediate risk as defined by D'Amico. The median follow-up was 60 (34-93) months. Twenty-seven patients (9.5%) were diagnosed with lymph node metastases. The median number of lymph nodes removed was 10 (7-14). The mean Briganti score was 19.3% in patients with lymph node involvement (LNI) and 6.3% in patients without LNI. Focusing on intermediate-risk patients, 91(52%) and 84 (48%) had a Briganti score < 5% and ≥ 5%, respectively, among whom 6 (6.6%) and 7(8.3%) had lymph node metastases. The accuracy of the score was low for intermediate risk patients with an area under the curve (AUC) of 53.1% (95% CI 0.45-0.61).

CONCLUSION

The Briganti nomogram in our retrospective cohort showed low accuracy for the prediction of lymph node involvement in an intermediate-risk prostate cancer population.

Influence of previous laparo-endoscopic inguinal hernia repair on performing radical prostatectomy: a nationwide survey among urological surgeons

BACKGROUND

There is considerable demographic overlap of inguinal hernia patients and prostate cancer patients. Previous laparo-endoscopic inguinal hernia mesh repairs can complicate subsequent radical prostatectomies due to adhesions and distortion of anatomic planes. This study aims to assess the experience of urological surgeons on the safety and feasibility of performing radical prostatectomies after laparo-endoscopic inguinal hernia mesh repair.

METHODS

For this cross-sectional study, an online 24 question survey was developed regarding the experience in performing a radical prostatectomy and pelvic lymph node dissection (PLND) with a prior preperitoneal inguinal hernia mesh repair. Between June 2016 and December 2017, the questionnaire was sent to all 68 urological surgeons performing radical prostatectomy in the Netherlands.

RESULTS

The response rate of urological surgeons was 69% (n = 47). The majority (77%) of urological surgeons perform robot-assisted laparoscopic prostatectomies. A previous preperitoneal inguinal hernia repair was reported by 40% of urological surgeons in 10-30% of patients undergoing radical prostatectomy. Radical prostatectomy with prior preperitoneal inguinal hernia mesh repair is considered more difficult by 49%, predominantly because of (occasionally to always) experienced longer operating times (88.4%), increased blood loss (46.5%), difficult dissection of Retzius space (88.4%), nerve-sparing difficulties (32.6%), less adequate PLND (69.8%), and bladder- (16.3%) or peritoneal perforations (27.9%). Additionally, 11.6% had performed mesh explantation, 16.3% had aborted radical prostatectomies, and 35.7% experienced increased inguinal hernia recurrences after radical prostatectomies with prior preperitoneal inguinal hernia mesh repair. More experienced urological surgeons reported an increased difficulty for all outcomes.

CONCLUSIONS

Laparo-endoscopic inguinal hernia mesh repair has a significant impact on performing a radical prostatectomy and PLND. Surgeons should postpone the inguinal hernia repair of patients in the workup for a radical prostatectomy, with the preferable option of performing the radical prostatectomy and inguinal hernia repair in the same procedure. Alternatively, a Lichtenstein repair can be performed.

The underestimated posterior lymphatic drainage of the prostate: An historical overview and preliminary anatomical study on cadaver

BACKGROUND

The evidence of pelvic lymph node metastases after radical prostatectomy (RP) with pelvic lymph node dissection (PLND) is one of the strongest prognostic factors for poor oncologic outcome. The extent of PLND, although representing a crucial step in RP, is still controversial. Currently, there is a critical drawback in clinical practice due to the lack of congruence between the known lymphatic drainage and cancer dissemination despite defined management by a surgical approach. We hypothesized the existence of alternative pathways for the lymphatic drainage of the prostate currently not considered in clinical daily practice.

METHODS

We carried out a literature review of the anatomic description of nodal drainage of prostate reported by online databases (MEDLINE/PubMed, EBSCO, Web of Science, Ovid, and Scopus) and the original texts since the 18th century, with an additional anatomical dissection on a human cadaver to confirm theoretical data.

RESULTS

The anatomical dissection study converged with the historical anatomical treatises in describing three groups of lymphatics devoted to carrying out prostatic nodal drainage. Apart from the ascending ducts from the cranial gland leading to the external iliac nodes; the lateral ducts leading to the hypogastric nodes; small lymphatic vessels from the posterior surface of the prostate, directed to the pararectal lymphatic plexus, in the direction of the lateral sacral lymph nodes and those at the sacral promontory (ie, pararectal and presacral lymph nodes) were observed.

CONCLUSIONS

Our preliminary findings demonstrate that lymphatic drainage of the prostate extends beyond standard nodal templates actually considered in surgical daily practice, despite the knowledge reported by historical anatomical treatises. Further anatomical and experimental evidence are needed to investigate anatomical variability in humans, as well as to add more topographical details.

Development and external validation of a nomogram to predict lymph node invasion after robot assisted radical prostatectomy

BACKGROUND

Prediction of lymph node invasion (LNI) after radical prostatectomy has been rarely assessed in robotically assisted laparoscopic radical prostatectomy (RALP) series. We aimed to develop and externally validate a pretreatment nomogram for the prediction of LNI following RALP in patients with high- and intermediate-risk prostate cancer.

METHODS

1654 RALP patients were prospectively collected between 2009 and 2016 from academic and community hospitals. We included patients with intermediate- and high-risk prostate cancer who underwent pelvic lymph node dissection (e-PLND). Logistic regression analysis was applied to construct a nomogram to predict LNI. Centers were randomly assigned to the training cohort (80%) and validation cohort (20%). The discriminative accuracies were evaluated by the areas under the curve and by the calibration plot. The net benefit of the nomogram to predict LNI was assessed by decision curve analysis and a cut-off was proposed.

RESULTS

In total, 14% of the patients in our cohort had pN1 disease. Applying logistic regression analysis, the following covariates were chosen to develop the nomogram: initial PSA, clinical T stage, biopsy Gleason sum, and proportion of positive biopsy cores. The nomogram showed a median discriminative accuracy of 73% and excellent calibration. The net benefit of the model ranged between 7% and 51% predicted risk of LNI. A cut-off to perform e-PLND was set at 7%. This would permit a 29% of avoidable e-PLND, missing 9.4% of patients with LNI.

CONCLUSIONS

We developed and externally validated a nomogram to predict LNI in patients treated with RALP from a prospective, multi-institutional, nationwide series. A risk of LNI > 7% is proposed as cut-off above which e-PLND is recommended.

Benefits of Elective Para-Aortic Radiotherapy for pN1 Prostate Cancer Using Arc Therapy (Intensity-Modulated or Volumetric Modulated Arc Therapy): Protocol for a Nonrandomized Phase II Trial

BACKGROUND

In patients with prostate cancer (PCa) with histopathologically proven pelvic lymph node (LN) metastasis (pN1) after extended pelvic lymph node dissection (ePLND), multimodality treatment consisting of treatment of the primary tumor and whole pelvic radiotherapy (WPRT) combined with androgen deprivation therapy (ADT) offers promising results, leading to better cause-specific survival rates compared with ADT alone. However, in case more than one pelvic LN is invaded by the tumor, approximately 40% of the patients relapse biochemically and clinically. Clinical relapse is present in the para-aortic LNs (M1a disease) in up to 77% of the relapsing cases.

OBJECTIVE

We hypothesize that, based on the evidence that positive LNs represent the door to hematogenous dissemination, elective para-aortic irradiation will reduce the development of both retroperitoneal nodal (M1a) and distant metastasis (M1b or M1c disease), postpone the need for palliative ADT, and prolong the time to castration-refractory disease.

METHODS

To test this hypothesis, we will conduct a prospective, nonrandomized phase II trial to study the efficacy of additional elective para-aortic radiotherapy (PART) in pN1 patients compared with those who were historically treated with adjuvant WPRT alone. We aim to include 137 patients with PCa and presence of pN1 disease after ePLND. With this number of patients, an improvement of 15% in the 5-year clinical relapse-free survival can be detected with a power of 80%.

RESULTS

Recruitment of patients for this trial started in 2017 and will be completed approximately by March 2020.

CONCLUSIONS

This is the first phase II trial to investigate the benefits of an elective PART in patients with PCa. The results of this trial will potentially serve as a sound base for a later randomized phase III trial. All participants are given a PART information sheet and required to give written informed consent. Results are expected to be published in a peer-reviewed journal.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03079323; https://clinicaltrials.gov/ct2/show/NCT03079323 (Archived by WebCite at http://www.webcitation.org/73ELimv1d).

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/11256.

Direct comparison of choline PET/CT and MRI in the diagnosis of lymph node metastases in patients with prostate cancer

BACKGROUND

Lymph node detection in prostate cancer is challenging and critical to determine treatment policy. Choline PET/CT (positron emission tomography/computed tomography) and magnetic resonance imaging (MRI) have been used for the evaluation of lymph node metastasis in patients with prostate cancer for the past decade. However, only limited patients underwent direct comparison studies.

PURPOSE

To evaluate the diagnostic performance of choline PET/CT compared with MRI imaging for detecting lymph node metastases in prostate cancer patients.

MATERIAL AND METHODS

Relevant English-language articles published before February 2018 were searched in PubMed database, Embase database, and Cochrane Library databases search using the keywords: (Prostate Neoplasm OR Prostate Cancer OR prostate carcinoma) and (Lymph Node) and (PET/CT OR positron emission tomography/computed tomography) and (choline or 2-hydroxy-N,N,N-trimethylethanaminium) and (magnetic resonance imaging OR MRI). Articles were included that directly compare the diagnostic performance and clinical utility of choline PET/CT and MRI for detecting lymph node metastases in prostate cancer patients. Study quality was assessed with QUADAS criteria. Analyses were performed on a per patient and a per node basis. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated using Meta-Disc 1.4 software. Summary receiver-operating characteristic (SROC) curves constructed.

RESULTS

A total of 362 patients from 8 studies involving fulfilled the inclusion criteria. On patient-based analysis, the pooled sensitivity, specificity, and DOR with a 95% confidence interval (CI) for choline PET/CT imaging were 0.59 (95%CI, 0.50-0.67), 0.92 (95%CI, 0.87-0.96), 17.37 (95%CI, 4.42-68.33), and for MRI imaging, they were 0.52 (95%CI, 0.44-0.61), 0.87 (95%CI, 0.81-0.92), 6.05 (95%CI, 3.09-11.85), respectively. On node-based, the corresponding values for choline PET/CT imaging were 0.51 (95%CI, 0.46-0.57), 0.99 (95%CI, 0.98-0.99), 65.55 (95%CI, 23.55-182.45), and for MRI imaging, they were 0.39 (95%CI, 0.34-0.44), 0.97 (95%CI, 0.96-0.97), 15.86 (95%CI, 8.96-28.05), respectively.

CONCLUSION

Choline PET/CT performed better than MRI imaging in evaluating the lymph nodes metastasis of prostate cancer patients and had the potential to be broadly applied in clinical practice.

Ga-68-PSMA PET/CT in treatment-naïve patients with prostate cancer: Which clinical parameters and risk stratification systems best predict PSMA-positive metastases?

PURPOSE

To evaluate the accuracy of clinical parameters and established pre-treatment risk stratification systems for prostate cancer (PCa) in predicting PSMA-positive metastases in men undergoing Ga-68-PSMA PET/CT as initial staging examination.

MATERIALS AND METHODS

A retrospective analysis in 108 consecutive treatment-naïve patients with biopsy-proven PCa undergoing Ga-68-PSMA PET/CT (median age, 72 years [range, 49-82 years]) was performed. Prediction of PSMA-positive metastases by serum PSA, clinical T stage (cT), ISUP group, percentage of positive biopsy cores, and derived risk scores (D'Amico risk classification system, Roach [RF], Yale formula [YF], and Briganti nomogram [BN]) was examined with ROC analysis.

RESULTS

Any PSMA-positive metastases were found in 36 of 108 patients, including LN metastases in 28 patients, extrapelvic LN metastases in 15 patients, and organ metastases in 19 patients (bone, 19; lung, 1). AUCs for PSA, cT, ISUP, and percentage of positive biopsy cores regarding PSMA-positive metastases did not differ significantly (range, 0.6-0.8; each P > 0.05). D'Amico (AUC, 0.61-0.64) was inferior to RF (0.76-0.83), YF (0.81-0.86), and BN (0.73 to 0.88; each P < 0.05). Among the 89 high-risk patients (D'Amico), decision for or against PET imaging based on RF (cut-off, >18.0), YF (>10.8), or BN (>8.0) would have prevented PSMA PET/CT in 4 (5%), 15 (17%), or 18 patients (20%), respectively, while preserving a sensitivity ≥95% for PSMA-positive metastases.

CONCLUSIONS

Clinical parameters and established risk stratification systems for PCa can predict Ga-68-PSMA PET-positive metastases in treatment-naïve patients. Especially YF and BN may improve identification of patients with the highest probability of metastatic disease detected by Ga-68-PSMA PET/CT.

External Validation of Models Predicting the Probability of Lymph Node Involvement in Prostate Cancer Patients

BACKGROUND

Multiple statistical models predicting lymph node involvement (LNI) in prostate cancer (PCa) exist to support clinical decision-making regarding extended pelvic lymph node dissection (ePLND).

OBJECTIVE

To validate models predicting LNI in Dutch PCa patients.

DESIGN, SETTING, AND PARTICIPANTS

Sixteen prediction models were validated using a patient cohort of 1001 men who underwent ePLND. Patient characteristics included serum prostate specific antigen (PSA), cT stage, primary and secondary Gleason scores, number of biopsy cores taken, and number of positive biopsy cores.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Model performance was assessed using the area under the receiver operating characteristic curve (AUC). Calibration plots were used to visualize over- or underestimation by the models.

RESULTS AND LIMITATIONS

LNI was identified in 276 patients (28%). Patients with LNI had higher PSA, higher primary Gleason pattern, higher Gleason score, higher number of nodes harvested, higher number of positive biopsy cores, and higher cT stage compared to patients without LNI. Predictions generated by the 2012 Briganti nomogram (AUC 0.76) and the Memorial Sloan Kettering Cancer Center (MSKCC) web calculator (AUC 0.75) were the most accurate. Calibration had a decisive role in selecting the most accurate models because of overlapping confidence intervals for the AUCs. Underestimation of LNI probability in patients had a predicted probability of <20%. The omission of model updating was a limitation of the study.

CONCLUSIONS

Models predicting LNI in PCa patients were externally validated in a Dutch patient cohort. The 2012 Briganti and MSKCC nomograms were identified as the most accurate prediction models available.

PATIENT SUMMARY

In this report we looked at how well models were able to predict the risk of prostate cancer spreading to the pelvic lymph nodes. We found that two models performed similarly in predicting the most accurate probabilities.

A practical guide for the use of indocyanine green and methylene blue in fluorescence-guided abdominal surgery

Near-infrared (NIR) fluorescence imaging is gaining clinical acceptance over the last years and has been used for detection of lymph nodes, several tumor types, vital structures and tissue perfusion. This review focuses on NIR fluorescence imaging with indocyanine green and methylene blue for different clinical applications in abdominal surgery with an emphasis on oncology, based on a systematic literature search. Furthermore, practical information on doses, injection times, and intraoperative use are provided.

Validation and head-to-head comparison of three nomograms predicting probability of lymph node invasion of prostate cancer in patients undergoing extended and/or sentinel lymph node dissection

PURPOSE

The updated Winter nomogram is the only nomogram predicting lymph node invasion (LNI) in prostate cancer (PCa) patients based on sentinel node (SN) dissection (sLND). The aim of the study was to externally validate the Winter nomogram and examine its performance in patients undergoing extended pelvic lymph node dissection (ePLND), ePLND combined with SN biopsy (SNB) and sLND only. The results were compared with the Memorial Sloan Kettering Cancer Center (MSKCC) and updated Briganti nomograms.

METHODS

This retrospective study included 1183 patients with localized PCa undergoing robot-assisted laparoscopic radical prostatectomy (RARP) combined with pelvic lymphadenectomy and 224 patients treated with sLND and external beam radiotherapy (EBRT), aiming to offer pelvic radiotherapy only in case of histologically positive SNs. In the RARP population, ePLND was applied in 956 (80.8%) patients,while 227 (19.2%) patients were offered ePLND combined with additional SNB.

RESULTS

The median numbers of removed nodes were 10 (interquartile range, IQR = 6-14), 15 (IQR = 10-20) and 7 (IQR = 4-10) in the ePLND, ePLND + SNB, and sLND groups, respectively. Corresponding LNI rates were 16.6%, 25.5% and 42%. Based on the AUC, the performance of the Briganti nomogram (0.756) in the ePLND group was superior to both the MSKCC (0.744) and Winter nomogram (0.746). The Winter nomogram, however, was the best predictor of LNI in both the ePLND + SNB (0.735) and sLND (0.709) populations. In the calibration analysis, all nomograms showed better accuracy in the low/intermediate risk patients, while in the high-risk population, an overestimation of the risk for LNI was observed.

CONCLUSION

The SN-based updated nomogram showed better prediction in the SN population. The results were also comparable, relative to predictive tools developed with (e)PLND, suggesting a difference in sampling accuracy between SNB and non-SNB. Patients who benefit most from the nomogram would be those with a low/intermediate risk of LN metastasis.

Validation of a rectal cancer outcome prediction model with a cohort of Chinese patients

The risk of local recurrence (LR), distant metastases (DM) and overall survival (OS) of locally advanced rectal cancer after preoperative chemoradiation can be estimated by prediction models and visualized using nomograms, which have been trained and validated in European clinical trial populations. Data of 277 consecutive locally advanced rectal adenocarcinoma patients treated with preoperative chemoradiation and surgery from Shanghai Cancer Center, were retrospectively collected and used for external validation. Concordance index (C-index) and calibration curves were used to assess the performance of the previously developed prediction models in this routine clinical validation population. The C-index for the published prediction models was 0.72 ± 0.079, 0.75 ± 0.043 and 0.72 ± 0.089 in predicting 2-year LR, DM and OS in the Chinese population, respectively. Kaplan-Meier curves indicated good discriminating performance regarding LR, but could not convincingly discriminate a low-risk and medium-risk group for distant control and OS. Calibration curves showed a trend of underestimation of local and distant control, as well as OS in the observed data compared with the estimates predicted by the model.

In conclusion, we externally validated three models for predicting 2-year LR, DM and OS of locally advanced rectal cancer patients who underwent preoperative chemoradiation and curative surgery with good discrimination in a single Chinese cohort. However, the model overestimated the local control rate compared to observations in the clinical cohort. Validation in other clinical cohorts and optimization of the prediction model, perhaps by including additional prognostic factors, may enhance model validity and its applicability for personalized treatment of locally advanced rectal cancer.

Whole body MRI (WB-MRI) assessment of metastatic spread in prostate cancer: Therapeutic perspectives on targeted management of oligometastatic disease

OBJECTIVES

To determine the proportion of prostate cancer (PCa) patients with oligometastatic disease (≤3 synchronous lesions) using whole body magnetic resonance imaging with diffusion-weighted imaging (WB-MRI/DWI). To determine the proportion of patients with nodal disease confined within currently accepted target areas for extended lymph node dissection (eLND) and pelvic external beam radiation therapy (EBRT).

SUBJECTS AND METHODS

Two radiologists reviewed WB-MRI/DWI studies in 96 consecutive newly diagnosed metastatic PCa patients; 46 patients with newly diagnosed castration naive PCa (mHNPC) and 50 patients with first appearance of metastasis during monitoring for non-metastatic castration resistant PCa (M0 to mCRPC). The distribution of metastatic deposits was assessed and the proportions of patients with oligometastatic disease and with LN metastases located within eLND and EBRT targets were determined.

RESULTS

Twenty-eight percent of mHNPC and 50% of mCPRC entered the metastatic disease with ≤3 sites. Bone metastases (BM) were identified in 68.8% patients; 71.7% of mHNPC and 66% mCRPC patients. Most commonly involved areas were iliac bones and lumbar spine. Enlarged lymph nodes (LN) were detected in 68.7% of patients; 69.6% of mHNPC and 68.0% of mCRPC. Most commonly involved areas were para-aortic, inter-aortico-cava, and external iliac areas. BM and LN were detected concomitantly in 41% of mHNPC and 34% of mCRPC. Visceral metastases were detected in 6.7%. Metastatic disease was confined to LN located within the accepted boundaries of eLND or pelvic EBRT target areas in only ≤25% and ≤30% of patients, respectively.

CONCLUSIONS

Non-invasive mapping of metastatic landing sites in PCa using WB-MRI/DWI shows that 28% of the mHNPC patients, and 52% of the mCRPC can be classified as oligometastatic, thus challenging the concept of metastatic targeted therapy. More than two thirds of metastatic patients have LN located outside the usually recommended targets of eLND and pelvic EBRT. Prophylactic or salvage treatments of these sole areas in patients with high-risk prostate cancer may not prevent the emergence of subsequent metastases. Prostate 76:1024-1033, 2016. © 2016 Wiley Periodicals, Inc.

Laparoscopic sentinel lymph node dissection in prostate cancer patients: the additional value depends on preoperative data

AIM

In intermediate- or high-risk prostate cancer (PC) patients, to avoid extended pelvic lymph node dissection (ePLND), the updated Briganti nomogram is recommended with the cost of missing 1.5 % of patients with lymph node invasion (LNI). Is it possible to reduce the percentage of unexpected LNI patients (nomogram false negative)? We used the isotopic sentinel lymph node (SLN) technique systematically associated with laparoscopic ePLND to assess the potential value of isotopic SLN method to adress this point.

METHODS

Two hundred and two consecutive patients had procedures with isotopic SLN detection associated with laparoscopic ePLND for high or intermediate risk of PC. The area under the curve (AUC) of the receiver operating characteristics (ROC) analysis was used to quantify the accuracy of different models as: the updated Briganti nomogram, the percentage of positive cores, and an equation of the best predictors of LNI. We tested the model cutoffs associated with an optimal negative predictive value (NPV) and the best cutoff associated with avoiding false negative SLN detection, in order to assist the clinician's decision of when to spare ePLND.

RESULTS

LNI was detected in 35 patients (17.2 %). Based on preoperative primary Gleason grade and percentage of positive cores, a bivariate model was built to calculate a combined score reflecting the risk of LNI. For the Briganti nomogram, the 5 % probability cutoff avoided ePLND in 53 % (108/202) of patients, missing three LNI patients (8.6 %), but all were detected by the SLN technique. For our bivariate model, the best cutoff was <10, leaving no patient with LNI due to positive SLN detection (four patients = 11.4 %), and avoiding ePLND in 52 % (105/202) of patients.

CONCLUSION

For patients with a low risk of LNI determined using the updated Briganti nomogram or bivariate model, SLN technique could be used alone for lymph node staging in intermediate- or high-risk PC patients.

The Role of Pelvic Lymph Node Dissection During Radical Prostatectomy in Patients With Gleason 6 Intermediate-risk Prostate Cancer

OBJECTIVE

To analyze the benefit of pelvic lymph node dissection (PLND) in patients with biopsy Gleason grade ≤ 6, cT ≤ 2b, and prostate-specific antigen (PSA) 10-20 ng/mL (main study cohort), as the indication for PLND during radical prostatectomy remains uncertain in patients with nonhigh-risk tumors.

MATERIALS AND METHODS

The main study cohort included 1383 patients with low intermediate-risk cancer undergoing radical prostatectomy with or without PLND between 1994 and 2013. Positive lymph node (LN) rates were reported and compared to patients with higher (≥20 ng/mL; n = 314) and lower (<10 ng/mL; n = 6861) PSA. Oncological outcome was assessed by Cox regressions in patients with a minimum follow-up of 5years.

RESULTS

In the main study cohort (PSA 10-20 ng/mL), PLND was performed in 867 (62.7%) patients with a median number of removed LNs of 11 (interquartile range 16-6). Positive LNs were detected in 3.3% of these patients. Compared to the main study cohort, patients with preoperatively higher PSA ≥ 20 ng/mL (or lower PSA < 10 ng/ml) underwent PLND in 83.8% (32.7%) of the cases, with 8.0% (1.8%) showing positive LNs. Median follow-up in the main study cohort was 84.5 months. Biochemical recurrence (BCR) occurred in 20.6% of these men. The 5-year and 10-year BCR-free survival rates were 82.2% and 75.6% for those with PLND, and 83.4% and 75.8% for patients without PLND. PLND was not a significant factor influencing BCR-free, metastasis-free, or cancer-specific survival in the main study cohort.

CONCLUSION

Positive LNs are rare in patients with Gleason grade ≤ 6, cT ≤ 2b, and PSA 10-20 ng/mL. Performing PLND had no statistical influence on oncologic outcome and therefore should be decided upon on an individual basis.

Pelvic lymph node dissection in prostate cancer: indications, extent and tailored approaches

PURPOSE

The purpose of this study is to review the current literature concerning the indication of pelvic lymph node dissection (PLND), its extent and complications in prostate cancer (PCa) staging, the available tools, and the future perspectives to assess the risk of lymph node invasion (LNI).

METHODS

A literature review was performed using the Medline, Embase, and Web of Science databases. The search strategy included the terms pelvic lymph nodes, PLND, radical prostatectomy, prostate cancer, lymph node invasion, biochemical recurrence, staging, sentinel lymph node dissection, imaging, and molecular markers.

RESULTS

PLND currently represents the gold standard for nodal staging in PCa patients. Available imaging techniques are characterized by poor accuracy in the prediction of LNI before surgery. On the contrary, an extended PLND (ePLND) would result into proper staging in the majority of the cases. Several models based on preoperative disease characteristics are available to assess the risk of LNI. Although ePLND is not associated with a substantial risk of severe complications, up to 10% of the men undergoing this procedure experience lymphoceles. Concerns over potential morbidity of ePLND led many authors to investigate the role of sentinel lymph node dissection in order to prevent unnecessary ePLND. Finally, the incorporation of novel biomarkers in currently available tools would improve our ability to identify men who should receive an ePLND.

CONCLUSIONS

Nowadays, the most informative tools predicting LNI in PCa patients consist in preoperative clinical nomograms. Sentinel lymph node dissection still remains experimental and novel biomarkers are needed to identify patients at a higher risk of LNI.

A molecular signature of PCA3 and ERG exosomal RNA from non-DRE urine is predictive of initial prostate biopsy result

BACKGROUND

New screening methods that can add predictive diagnostic value for aggressive (high-grade, Gleason score ⩾ 7) prostate cancer (PCa) are needed to reduce unnecessary biopsies for patients with non-aggressive PCa. This is particularly important for men presenting for an initial biopsy with an equivocal PSA in the 2-10 ng ml(-1) range. PCA3 and ERG are biomarkers that can add predictive value for PCa in urine; however, with a limited utility as a digital rectal exam (DRE) is required.

METHODS

First-catch urine samples were collected at six sites from men scheduled to undergo a prostate biopsy. Exosomal RNA was extracted, RNA copy numbers of ERG and PCA3 were measured by reverse transcription-quantitative PCR (RT-qPCR), and the EXO106 score (the sum of normalized PCA3 and ERG RNA levels) was computed. Performance was compared with standard of care (SOC; PSA, age, race or family history) parameters. Contingency table, logistic regression, receiver operating characteristics curve and box-plot analyses were performed.

RESULTS

In this cohort (N=195), a dichotomous EXO106 score demonstrated good clinical performance in predicting biopsy result for both any cancer and high-grade disease. For high-grade disease, the negative and positive predictive values were 97.5% and 34.5%, respectively. The discrimination between high-grade and Gleason score ⩽ 6 (including benign) biopsy results by a combination of EXO106 and SOC (area under the curve (AUC)=0.803) was significantly improved compared with SOC without EXO106 (AUC=0.6723, P=0.0009). The median EXO106 score correlated (P<0.001; Spearman's rank order) with histologic grade.

CONCLUSIONS

A novel molecular signature (EXO106 score) derived from non-DRE urine demonstrated independent, negative predictive value for the diagnosis of high-grade PCa from initial biopsy for men with 'gray zone' serum PSA levels. Its use in the biopsy decision process could result in fewer prostate biopsies for clinically insignificant disease.

A clinicogenetic model to predict lymph node invasion by use of genome-based biomarkers from exome arrays in prostate cancer patients

Purpose

Genetic variations among prostate cancer (PCa) patients who underwent radical prostatectomy (RP) and pelvic lymph node dissection were evaluated to predict lymph node invasion (LNI). Exome arrays were used to develop a clinicogenetic model that combined clinical data related to PCa and individual genetic variations.

Materials and Methods

We genotyped 242,186 single-nucleotide polymorphisms (SNPs) by using a custom HumanExome BeadChip v1.0 (Illumina Inc.) from the blood DNA of 341 patients with PCa. The genetic data were analyzed to calculate an odds ratio as an estimate of the relative risk of LNI. We compared the accuracies of the multivariate logistic model incorporating clinical factors between the included and excluded selected SNPs. The Cox proportional hazard models with or without genetic factors for predicting biochemical recurrence (BCR) were analyzed.

Results

The genetic analysis indicated that five SNPs (rs75444444, rs8055236, rs2301277, rs9300039, and rs6908581) were significant for predicting LNI in patients with PCa. When a multivariate model incorporating clinical factors was devised to predict LNI, the predictive accuracy of the multivariate model was 80.7%. By adding genetic factors in the aforementioned multivariate model, the predictive accuracy increased to 93.2% (p=0.006). These genetic variations were significant factors for predicting BCR after adjustment for other variables and after adding the predictive gain to BCR.

Conclusions

Based on the results of the exome array, the selected SNPs were predictors for LNI. The addition of individualized genetic information effectively enhanced the predictive accuracy of LNI and BCR among patients with PCa who underwent RP.

Defining the radiobiology of prostate cancer progression: An important question in translational prostate cancer research

Prostate cancer is one of the most common malignancies affecting men worldwide. High mortality rates from advanced and metastatic prostate cancer in the United States are contrasted by a relatively indolent course in the majority of cases. This gives hope for finding methods that could direct personalized diagnostic, preventative, and treatment approaches to patients with prostate cancer. Recent advances in multiparametric magnetic resonance imaging (MP-MRI) offer a noninvasive diagnostic intervention which allows correlation of prostate tumor image characteristics with underlying biologic evidence of tumor progression. The power of MP-MRI includes examination of both local invasion and nodal disease and might overcome the challenges of analyzing the multifocal nature of prostate cancer. Future directions include a careful analysis of the genomic signature of individual prostatic lesions utilizing image-guided biopsies. This review examines the diagnostic potential of MRI in prostate cancer.

One-step TNM staging of high-risk prostate cancer using magnetic resonance imaging (MRI): toward an upfront simplified "all-in-one" imaging approach?

BACKGROUND

Multiparametric magnetic resonance imaging (mpMRI) is the standard for local prostate cancer (PCa) staging. Whole-body MRI (wbMRI) has shown capabilities for metastatic screening. This study assesses the feasibility and value of an all-in-one AJCC TNM staging of PCa during a unique MRI session combining mpMRI and wbMRI.

METHODS

Thirty consecutive patients with "high-risk" PCa prospectively underwent mpMRI of the prostate and wbMRI, in addition to (99m) Tc bone scan (BS), completed with standard X-rays (±TXR) and contrast enhanced CT for distant staging. For the statistical analysis, a "best valuable comparator" (BVC) combining a panel review of all available baseline and follow-up imaging, biological, and clinical data was used to adjudicate lymph node and bone metastatic status.

RESULTS

Prostate mpMRI was analyzed using ESUR guidelines. Sensitivity of BS ± TXR combined with CT and of wbMRI for detecting metastases (bones or nodes) was 85% and 100%, respectively, and specificity was 88% and 100%, respectively. For the overall staging of the patients as being either N0M0 or having disease extension beyond the prostate, wbMRI was superior to the combination of BS and CT (improvement in all ROC characteristics and of AUC by 13.6% (95% CI: +0.7% to +26.5%, P = 0.039)). The main limitation is the limited number of patients.

CONCLUSIONS

AJCC M and N staging using wbMRI is feasible during the same imaging session as mpMRI performed for T staging, in less then one hour. wbMRI outperforms BS ± TXR and abdomino-pelvic CT work up for discriminating subsets of patients with or without distant spread of the cancer.

The role of radical prostatectomy and lymph node dissection in lymph node-positive prostate cancer: a systematic review of the literature

CONTEXT

Because pelvic lymph node (LN)-positive prostate cancer (PCa) is generally considered a regionally metastatic disease, surgery needs to be better defined.

OBJECTIVE

To review the impact of radical prostatectomy (RP) and pelvic lymph node dissection (PLND), possibly in conjunction with a multimodal approach using local radiotherapy and/or androgen-deprivation therapy (ADT), in LN-positive PCa.

EVIDENCE ACQUISITION

A systematic Medline search for studies reporting on treatment regimens and outcomes in patients with LN-positive PCa undergoing RP between 1993 and 2012 was performed.

EVIDENCE SYNTHESIS

RP can improve progression-free and overall survival in LN-positive PCa, although there is a lack of high-level evidence. Therefore, the former practice of aborting surgery in the presence of positive nodes might no longer be supported by current evidence, especially in those patients with a limited LN tumor burden. Current data demonstrate that the lymphatic spread takes an ascending pathway from the pelvis to the retroperitoneum, in which the internal and the common iliac nodes represent critical landmarks in the metastatic distribution. Sophisticated imaging technologies are still under investigation to improve the prediction of LN-positive PCa. Nonetheless, extended PLND including the common iliac arteries should be offered to intermediate- and high-risk patients to improve nodal staging with a possible benefit in prostate-specific antigen progression-free survival by removing significant metastatic load. Adjuvant ADT has the potential to improve overall survival after RP; the therapeutic role of a trimodal approach with adjuvant local radiotherapy awaits further elucidation. Age is a critical parameter for survival because cancer-specific mortality exceeds overall mortality in younger patients (<60 yr) with high-risk PCa and should be an impetus to treat as thoroughly as possible.

CONCLUSIONS

Increasing evidence suggests that RP and extended PLND improve survival in LN-positive PCa. Our understanding of surgery of the primary tumor in LN-positive PCa needs a conceptual change from a palliative option to the first step in a multimodal approach with a significant improvement of long-term survival and cure in selected patients.

Pelvic lymph node dissection during robot-assisted radical prostatectomy: efficacy, limitations, and complications-a systematic review of the literature

CONTEXT

Pelvic lymph node dissection (PLND) in prostate cancer is the most effective method for detecting lymph node metastases. However, a decline in the rate of PLND during radical prostatectomy (RP) has been noted. This is likely the result of prostate cancer stage migration in the prostate-specific antigen-screening era, and the introduction of minimally invasive approaches such as robot-assisted radical prostatectomy (RARP).

OBJECTIVE

To assess the efficacy, limitations, and complications of PLND during RARP.

EVIDENCE ACQUISITION

A review of the literature was performed using the Medline, Scopus, and Web of Science databases with no restriction of language from January 1990 to December 2012. The literature search used the following terms: prostate cancer, radical prostatectomy, robot-assisted, and lymph node dissection.

EVIDENCE SYNTHESIS

The median value of nodal yield at PLND during RARP ranged from 3 to 24 nodes. As seen in open and laparoscopic RP series, the lymph node positivity rate increased with the extent of dissection during RARP. Overall, PLND-only related complications are rare. The most frequent complication after PLND is symptomatic pelvic lymphocele, with occurrence ranging from 0% to 8% of cases. The rate of PLND-associated grade 3-4 complications ranged from 0% to 5%. PLND is associated with increased operative time. Available data suggest equivalence of PLND between RARP and other surgical approaches in terms of nodal yield, node positivity, and intraoperative and postoperative complications.

CONCLUSIONS

PLND during RARP can be performed effectively and safely. The overall number of nodes removed, the likelihood of node positivity, and the types and rates of complications of PLND are similar to pure laparoscopic and open retropubic procedures.