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

Outcomes of robot-assisted laparoscopic extended pelvic lymph node dissection for prostate Cancer

INTRODUCTION

Extended pelvic lymph node dissection (ePLND) in men undergoing robot-assisted laparoscopic radical prostatectomy (RARP) is a widely used procedure. However, little is known about anatomical site-specific yields and subsequent metastatic patterns in these patients.

PATIENTS AND METHODS

Data on a consecutive series of 1107 patients undergoing RARP at our centre between 2004 and 2018 were analysed. In men undergoing LN dissection, the internal, external and obturator nodes were removed and sent in separately. We performed an analysis of LN yields in total and for each anatomical zone, patterns of LN metastases and complications. Oncological outcome in pN+ disease was assessed including postoperative PSA persistence and survival.

RESULTS

A total of 823 ePLNDs were performed in the investigated cohort resulting in 98 men being diagnosed as pN+ (8.9%). The median (IQR) LN yield was 19 (14-25), 10 (7-13) on the right and 9 (6-12) on the left side (P < 0.001). A median of six (4-8) LNs were retrieved from the external, three (1-6) from the internal iliac artery, and eight (6-12) from the obturator fossa. More men had metastatic LNs on the right side compared to the left (41 vs. 19). Symptomatic lymphoceles occurred exclusively in the ePLND group (2.3% vs. 0%, p = 0.04). Postoperatively, 47 (47.9%) of men with pN+ reached a PSA of < 0.1μg/ml. There was no association between a certain pN+ region and postoperative PSA persistence or BCRFS. The estimated cancer specific survival rate at 5 years was 98.5% for pN+ disease.

CONCLUSION

Robot-assisted laparoscopic ePLND with a high LN yield and low complication rate is feasible. However, we observed an imbalance in more removed and positive LNs on the right side compared to the left. A high rate of postoperative PSA persistence and early recurrence in pN+ patients might indicate a possibly limited therapeutical value of the procedure in already spread disease. Yet, these men demonstrated an excellent survival.

A Practical Guide to the Pearls and Pitfalls of PSMA PET Imaging

Prostate-specific membrane antigen (PSMA)-targeted PET agents have revolutionized the care of patients with prostate cancer, supplanting traditional methods of imaging prostate cancer, and improving the selection and delivery of therapies. This has led to a rapid expansion in both the number of PSMA PET scans performed and the imaging specialists required to interpret those scans. To aid those imagers and clinicians who are new to the interpretation of PSMA PET, this review provides an overview of the interpretation of PSMA PET/CT imaging and pearls for overcoming commonly encountered pitfalls. We discuss the physiologic distribution of the clinically available PSMA-targeted radiotracers, the commonly encountered patterns of prostate cancer spread, as well as the benign and malignant mimics of prostate cancer. Additionally, we review the standardized PSMA PET reporting systems and the role of PSMA in selecting appropriate patients for PSMA-targeted therapies.

Degenerative Changes in Aging Human Pelvic Lymph Nodes-A Reason to Rethink Staging and Therapy of Regional Malignancies?

Lymph node metastases are common in pelvic urological tumors, and the age-related remodeling process of the pelvic lymph nodes influences metastatic behavior. The aim of this work is to characterize age-related degenerative changes in the pelvic lymph nodes with respect to their occurrence and extent. A total of 5173 pelvic lymph nodes of 390 patients aged 44 to 79 years (median 68 years, IQR 62-71 years) were histologically examined for degenerative structural changes. Lymph node size, lipomatous atrophy, capsular fibrosis, framework fibrosis, and calcifications were recorded semi-quantitatively and evaluated by age group. Significantly more lymph nodes <10 mm were found in older patients (p = 0.001). The incidence of framework fibrosis, capsular fibrosis, and calcifications increased significantly with increasing patient age (p < 0.001). In lipomatous atrophy, an increase in mild to moderate lipomatous atrophy was observed with increasing age (p < 0.001). In this, the largest study to date on this topic, age-related degenerative changes in pelvic lymph nodes were proven. Due to the consecutive decrease in hte filtration function of pelvic lymph nodes with increasing age, staging and therapy of metastatic pelvic urologic carcinomas should be reconsidered.

Radical prostatectomy findings in patients with locally aggressive Grade group 5 prostatic adenocarcinoma and negative limited or extended pelvic lymph node dissection

Current management options for high-risk prostate cancer (PCa) patients include radical prostatectomy with lymph node dissection and other local or systemic therapeutic approaches. However, there is paucity of data in the pathology literature on the radical prostatectomy findings in patients with locally aggressive Grade group 5 PCa with negative limited or extended lymph node dissection. A search was made through our Urologic Pathology files and consults of the senior author for patients who had radical prostatectomy specimens with locally aggressive Grade group 5 PCa and limited or extended lymph node dissection from 2010 to 2022. Patients with lymph node metastasis were excluded. Clinicopathologic and follow up data were obtained. Forty-two patients were included in the study. Mean age was 64 years (range: 49-79 years). Forty-one (98 %) patients had PCa Gleason score 4 + 5 = 9 and 1 (2 %) patient had Gleason score 5 + 4 = 9. Extraprostatic extension and/or bladder neck invasion was present in 30 (71 %) patients and seminal vesicle invasion was present in 20 (48 %) patients, of which 10 (50 %) were bilateral. Extended lymph node dissection was performed in 18 patients with mean of 22 lymph nodes (range: 6-51 lymph nodes). Limited lymph node dissection was performed in 24 patients with mean of 7 lymph nodes (range: 2-25 lymph nodes). This study demonstrates that a subset of patients with very advanced/high grade PCa still benefit from radical prostatectomy/tumor debulking even in the setting of positive margins, and may not have lymph node metastasis.

Identifying the Candidates Who Will Benefit From Extended Pelvic Lymph Node Dissection at Radical Prostatectomy Among Patients With Prostate Cancer

PURPOSE

The therapeutic effect of extended pelvic lymph node dissection (PLND) in prostate cancer (PCa) patients is still controversial. The aim of this study was to identify the PCa patients who may benefit from extended PLND based on the 2012 Briganti nomogram.

MATERIALS AND METHODS

PCa patients who underwent radical prostatectomy (RP) plus PLND between 2010 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The probability of lymph node invasion (LNI), determined using the 2012 Briganti nomogram, was used to stratify the patients. The endpoints were overall survival (OS) and cancer-specific survival (CSS). Propensity score matching (PSM) was performed to account for potential differences between patients with and without extended PLND. Univariable and multivariable Cox regression was used to analyze the association between the number of removed nodes (NRN) and survival. Kaplan-Meier analysis was performed to estimate OS and CSS. Extended PLND was defined as NRN >75th percentile.

RESULTS

A total of 27,690 patients were included in the study. NRN was not an independent predictor of OS (p = 0.564). However, in patients with probability of LNI ≥37, multivariable analyses showed that increased NRN was associated with improved OS (hazard ratio [HR] = 0.963; p = 0.002). The 5-y OS rate was significantly higher for patients with NRN ≥12 than those with NRN <12 (94.9% vs. 91.9%, respectively; p = 0.015). In the PSM cohort, among patients with probability of LNI ≥37, multivariable analyses showed that increased NRN was associated with improved OS (HR = 0.961; p = 0.004). In addition, the 5-y OS rate was significantly higher for patients with NRN ≥12 than those with NRN <12 (94.9% vs. 89.8%, respectively; p = 0.002). However, NRN was not an independent predictor of CSS in any LNI risk subgroup (all p >0.05).

CONCLUSION

Extensive PLND might be associated with improved survival in PCa patients with a high risk of LNI, which supports the use of extended PLND in highly selected PCa patients. The results need to be validated in prospective studies with long-term follow-up.

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.

Validating Modern NRG Oncology Pelvic Nodal and Groupe Francophone de Radiothérapie Urologique Prostate Bed Contouring Guidelines for Post-Prostatectomy Salvage Radiation: A Secondary Analysis of the LOCATE Trial

PURPOSE

We used the patterns of recurrence on ¹⁸F-fluciclovine positron emission tomography (PET)-computed tomography (CT) in patients enrolled in the LOCATE trial after prostatectomy to evaluate how well the most recent NRG Oncology and Groupe Francophone de Radiothérapie Urologique (GFRU) contouring recommendations encompassed all sites of recurrence in the prostate fossa and pelvic nodes in comparison to former Radiation Therapy Oncology Group (RTOG) recommendations.

METHODS AND MATERIALS

Patients with biochemically recurrent prostate cancer after radical prostatectomy with a positive finding within the prostate fossa or pelvic nodes on ¹⁸F-fluciclovine PET/CTs were identified from the LOCATE patient population. Areas of gross disease were delineated. Prostate fossa contours were delineated using both the 2010 RTOG consensus guidelines and the recently published 2020 GFRU consensus guidelines. Pelvic nodes were contoured with both the 2009 RTOG consensus guidelines and the 2020 NRG consensus guidelines. The performance of the contouring guidelines was assessed by determining what proportion of gross recurrent lesions were encompassed completely or marginally.

RESULTS

Of the 213 patients within the LOCATE trial, 45 patients were eligible for analysis with positive ¹⁸F-fluciclovine PET findings. Of the 30 total prostate fossa recurrences, the 2010 RTOG contour covered 20 (67%) and missed or marginally covered 10 (33%). The 2020 GFRU contour covered 27 recurrences (90%), and missed or marginally covered 3 (10%). Of the 43 total nodal recurrences, the 2009 RTOG pelvic nodal contour covered 29 nodes (67%), and missed or marginally covered 14 (32%). The 2020 NRG pelvic nodal contour covered 43 nodes (100%), with no misses or marginal coverage.

CONCLUSIONS

This secondary analysis of the LOCATE trial exemplifies the improved coverage of the latest prostate fossa contouring recommendations from the GFRU. Similarly, it also validates the updated 2020 NRG pelvic nodal contouring guidelines by demonstrating improved coverage of recurrent disease in this patient population.

Development and validation of the 3D U-Net algorithm for segmentation of pelvic lymph nodes on diffusion-weighted images

Background

The 3D U-Net model has been proved to perform well in the automatic organ segmentation. The aim of this study is to evaluate the feasibility of the 3D U-Net algorithm for the automated detection and segmentation of lymph nodes (LNs) on pelvic diffusion-weighted imaging (DWI) images.

Methods

A total of 393 DWI images of patients suspected of having prostate cancer (PCa) between January 2019 and December 2020 were collected for model development. Seventy-seven DWI images from another group of PCa patients imaged between January 2021 and April 2021 were collected for temporal validation. Segmentation performance was assessed using the Dice score, positive predictive value (PPV), true positive rate (TPR), and volumetric similarity (VS), Hausdorff distance (HD), the Average distance (AVD), and the Mahalanobis distance (MHD) with manual annotation of pelvic LNs as the reference. The accuracy with which the suspicious metastatic LNs (short diameter > 0.8 cm) were detected was evaluated using the area under the curve (AUC) at the patient level, and the precision, recall, and F1-score were determined at the lesion level. The consistency of LN staging on an hold-out test dataset between the model and radiologist was assessed using Cohen’s kappa coefficient.

Results

In the testing set used for model development, the Dice score, TPR, PPV, VS, HD, AVD and MHD values for the segmentation of suspicious LNs were 0.85, 0.82, 0.80, 0.86, 2.02 (mm), 2.01 (mm), and 1.54 (mm) respectively. The precision, recall, and F1-score for the detection of suspicious LNs were 0.97, 0.98 and 0.97, respectively. In the temporal validation dataset, the AUC of the model for identifying PCa patients with suspicious LNs was 0.963 (95% CI: 0.892–0.993). High consistency of LN staging (Kappa = 0.922) was achieved between the model and expert radiologist.

Conclusion

The 3D U-Net algorithm can accurately detect and segment pelvic LNs based on DWI images.

Diagnostic accuracy of 18F-fluciclovine PET/CT in primary lymph node staging of prostate cancer

INTRODUCTION

To determine preoperative diagnostic accuracy of 18F-fluciclovine PET/CT-scan in detection (or exclusion) of lymph node metastases (LNM) in men with prostate cancer (PCa) in comparison to the histopathological results of the extended pelvic lymph node dissection (e-PLND).

METHODS

A retrospective medical records-based cohort study, including 47 men with primary PCa who received 18F-fluciclovine PET/CT and subsequent e-PLND for lymph node staging. Incidence and number of visualized LNM, their locations and diameters on 18F-fluciclovine PET/CT were recorded in comparison to the histopathological results of the e-PLND as reference. Positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity and diagnostic accuracy of 18F-fluciclovine PET/CT were calculated on the basis of histopathology results after e-PLND.

RESULTS

Forty-seven men were eligible for analysis. Median lymph node yield was 19 (range 10-70). A total of 996 lymph nodes were removed, and 59 metastases were found in 21 cases (45%). Preoperative PET was issued 'positive' in 11 men and in 9 of them (82%) this was histopathologically confirmed resulting in a PPV of 82% (95% CI, 51-96). On the contrary, PET was issued 'negative' in 36 cases, but in 12 of them (33%) metastases were detected in the e-PLND specimen, resulting in an NPV of 67% (95% CI, 50-80). The patient-based sensitivity was 43% (95% CI, 24-64) and the patient-based specificity rate was 92% (95% CI, 75-99), whereas overall diagnostic accuracy was established to be 70% in the present cohort.

CONCLUSION

18F-Fluciclovine PET/CT has a high specificity and positive predicted value for the presence of LNM in men with prostate cancer. However, the sensitivity and NPV seem to be limited to exclude the absence of LNM at a clinically acceptable level. Prospective evaluation is necessary to define patients who may benefit from 18F-fluciclovine PET/CT as a triage test for the indication for e-PLND.

Prognostic Models for Patients With Gleason Score 9 Prostate Cancer: A Population-Based Study

Purpose: Gleason score (GS) system is one of the most widely used histological grading methods for prostate cancer (PCa) all over the world. GS can be obtained by adding the primary Gleason pattern (GP) and secondary GP. Different proportions of GP 4 and GP 5 in prostate specimens can both lead to GS 9. In this study, we explored whether GP 5 + 4 or GP 4 + 5 was associated with different prognoses among patients with GS 9 PCa.

Materials and methods: A retrospective population-based study was conducted on 10,124 subjects diagnosed with GS 9 PCa between 2004 and 2009 from the Surveillance, Epidemiology, and End Results program. A 1:1 propensity-score matching (PSM) was performed to balance the baseline characteristics between the GP 4 + 5 and 5 + 4 groups and to compare the prognoses between the two groups. Cox regression analysis and Fine-Gray competing risk regression models were adopted to screen the covariates significantly associated with all-cause mortality (ACM) and cancer-specific mortality (CAM).

Results: GP 5 + 4 was associated with higher risks of ACM and CSM before or after PSM than GP 4 + 5. In the original cohort, there were eight independent predictors for ACM, which were age at diagnosis, race, AJCC NM stage, PSA levels, treatments, GP, and marital status, confirmed by the Cox analysis; and nine independent predictors for CSM, which were age at diagnosis, race, AJCC TNM stage, PSA levels, treatments, GP, and marital status, confirmed by the competing-risk model.

Conclusion: GP 5 + 4 was associated with a poorer overall survival and cancer-specific survival compared with GP 4 + 5.

[It is unclear whether pelvic lymphadenectomy is of oncological benefit in prostate cancer]

Fossati's 2017 review questions the value of pelvic lymphadenectomy (pLA) in radical prostatectomy (RP) because available studies fail to show any oncological benefit. Our finding that no spread of metastatic lymph nodes (LN) has been demonstrated is based on registry data, clinical trials without evidence of pLA benefit and considerations of the genetic link between LN metastasis and distant metastases. The improved imaging with ⁶⁸GaPSMA-PET-CT facilitates the detection of metastases and thus the omission of pLA as diagnostic intervention, thereby avoiding typical complications. The question whether pLA, or a multimodal treatment concept, might benefit intermediate and high-risk patients can only be answered by an RCT which, above all, must consider the incompletely removed primary as a source of metastatic spread.

Pathologic nodal downstaging in men with clinically involved lymph nodes undergoing radical prostatectomy: Implications for definitive locoregional therapy

A prostate cancer (CaP) patient with nonmetastatic but clinical positive lymph nodes (cN+) represents a difficult clinical scenario. We compare overall survival (OS) between cN+ men that underwent radical prostatectomy (RP) and were found to have negative node status (pN) with those found to have positive nodal status (pN+), and assess predictors of discordant nodal status. We queried the National Cancer Data Base between 2004 and 2015 for patients that were cT1-3 cN+ cM0 CaP treated with RP. Patients with 0 nodes, cT4, or cM1 disease were excluded. We compared groups based on pathologic nodal status: Discordant (cN+ -> pN) & Concordant (cN+ -> pN+). Kaplan Meier estimations were used to compare OS. Logistic regression was used to determine possible predictors of nodal status. We find that of 6470 cN+ patients, 1,367 (21.1%) underwent RP, 866 (13.4%) had confirmed nodal status. Discordant status was found in 159 (18.4%) and concordant staging in 707 (81.6%). Differences exist in PSA at diagnosis (7.3 vs. 11.2), biopsy group, # of nodes examined (7 vs. 10), race, and Charlson index. Discordant staging had longer OS compared to Concordant staging (P = 0.007) and similar OS to a 3:1 matched cohort of high risk localized CaP patients used as reference (P = 0.46). Lower Gleason Score (GG1-3) was associated with an increased likelihood of discordant staging. Clinical nodal staging is associated with a substantial false positive rate. Discordant status had better OS than Concordant status and similar OS to matched patients with localized CaP. Clinical nodal staging may inappropriately lead to noncurative therapy in a substantial number of men with potentially curable disease.

Clinical outcomes of definitive whole pelvic radiotherapy for clinical lymph node metastatic prostate cancer

Background

In this study, we aim to present the clinical outcomes of radiotherapy (RT) in clinical pelvic lymph node‐positive prostate cancer (cN1) patients. We also analyze the prognostic factors with focus on RT dose escalation to metastatic lymph nodes (LN).

Methods

We retrospectively analyzed the data from cN1 patients who were treated with definitive RT and androgen deprivation therapy (ADT) between June 2004 and February 2016. All patients received localized irradiation to the prostate region and whole pelvis irradiation. Some patients received intensity‐modulated radiation therapy with RT dose escalation to metastatic LN. Univariate analyses using log‐rank test were performed to find prognostic factors between patient subgroups.

Results

Fifty‐one consecutive patients were identified. The median follow‐up period for all patients was 88 (range 20‐157) months. Primary Gleason pattern and LN RT dose were statistically significant prognostic factors for relapse‐free survival (RFS) and distant metastasis‐free survival (DMFS). Especially, RT dose escalation (60 Gy or more) to metastatic LN significantly improved RFS and DMFS compared with standard dose RT (4‐year RFS 90.6% vs 82.1%, 7‐year RFS 90.6% vs 58.0%, P = .015; 4‐year DMFS 90.6% vs 82.1%, 7‐year DMFS 90.6% vs 62.8%, P = .023). The following factors were all statistically significant for biochemical relapse‐free survival (BRFS): T stage, LN RT dose, local RT dose, and ADT duration period. Any significantly different toxicity was not seen for each LN or local RT dose except for the incident rate of grade 2 or more acute urinary retention, which was significantly higher in the higher LN RT dose (60 Gy or more) group by the Chi‐square test.

Conclusions

RT dose escalation to metastatic LN in cN1 patients improves BRFS, RFS, and DMFS at 4 and 7 years, without increasing severe adverse events.

Positive node burden rather than the number of removed nodes impacts survival in patients with node-positive prostate cancer

BACKGROUND

The value of pelvic lymphadenectomy during radical prostatectomy (RP) remains controversial. This study aims to test the effects of the number of removed lymph nodes (RLN), positive nodes (pLN), and pLN ratio (pLNR) on cancer-specific survival (CSS) in patients with node-positive prostate cancer (PCa).

METHODS

A total of 2458 patients with a greater than 5% probability of lymph node invasion according to the updated Briganti nomogram who harboured pathologically confirmed positive nodes in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were identified. Multivariable Cox regression with forward stepwise selection was performed to identify independent risk factors for CSS. Maximally selected rank statistics were used to determine the most informative cut-off value for pLN and pLNR.

RESULTS

The median pLN counts and RLN in the study were two (interquartile range [IQR] 1- 3) and 18 (IQR 15-23), respectively. The RLN counts could not predict CSS, while the higher pLN and pLNR were associated with worse CSS (hazard ratio [HR], 1.11; p < 0.001 and HR, 1.01; p < 0.001, respectively). Patients with ≤ 2 pLN or pLNR ≤ 20% had significantly better CSS than those with pLN > 2 or pLNR > 20% (HR, 1.38 (1.08-1.77); p = 0.009; HR, 1.77 (1.41-2.22); p < 0.001, respectively).

CONCLUSIONS

In patients with node-positive PCa, pelvic lymphadenectomy provides important information for staging, prognosis, and guiding after RP therapy; however, it does not play a therapeutic role. The pLN counts and pLNR were independent predictors of CSS.

Overall survival comparison between androgen deprivation therapy (ADT) plus external beam radiation therapy (EBRT) vs ADT plus EBRT with brachytherapy boost in clinically node-positive prostate cancer

PURPOSE

Optimal therapy for clinically node-positive, nonmetastatic (cN1) prostate cancer (PC) patients remains controversial, ranging from aggressive local therapy to palliative systematic therapy alone. Despite guideline support, it is unclear if a brachytherapy (BT) boost should be considered for cN1 patients as these patients were excluded from randomized trials establishing its benefit. Herein, we compare definitive radiation therapy (RT) with or without a BT boost in cN1 PC.

METHODS AND MATERIALS

The National Cancer Database was used to identify men with cN1 PC treated with definitive RT and concomitant androgen deprivation therapy between 2004 and 2013. Overall survival (OS) was compared between those who received external beam RT (EBRT) or combination EBRT plus BT boost (EBRT + BT) using Kaplan-Meier with propensity score matching and Cox proportional hazards.

RESULTS

With a median followup of 48.5 months, 1,650 patients were eligible for this analysis, 103 (6.2%) of whom received EBRT + BT. Younger age, no medical comorbidities, and Gleason score of six were associated with higher likelihood of receiving EBRT + BT over EBRT alone. The mean (median) OS for EBRT and EBRT + BT was 99.0 (110.6) months vs 109.2 (not reached) months, respectively (p = 0.048). However, no significance difference in OS was observed between the groups after propensity score matching. On multivariable analysis, EBRT + BT was not significantly associated with improved OS (adjusted HR 0.67, 95% CI, 0.41-1.07, p = 0.098).

CONCLUSIONS

In this retrospective, observational study of patients with cN1 PC treated with definitive RT and concomitant androgen deprivation therapy, EBRT + BT had an unadjusted improvement in OS compared with EBRT alone that lost statistical significance after multivariable adjustment and propensity score matching.

Undetectable PSA after radical prostatectomy is more likely in low burden N+ prostate cancer patients when an extended lymph node dissection is performed

OBJECTIVES

To analyze the likelihood of undetectable PSA (< 0.01 ng/mL) after extended (ePLND) versus standard pelvic lymph-nodes dissection (sPLND) in pN+ patients.

MATERIALS AND METHODS

The institutional prospectively maintained Prostate Cancer Database was queried for patients who underwent radical prostatectomy with PLND and were found with 3or less lymph-nodal metastases between 2007 and 2017. The extension of the PLND was defined according to the number of lymph-nodes (LN) removed. Patients in the 75th or higher percentile of lymph-nodes removed were considered as the ePLND group; patients in the 25th or lower percentile in the sPLND group. Groups were compared in clinical and pathological variables. Student T-test was used for comparing continuous variables; chi-square test was used for categorical variables. Multivariable logistic regression assessed the probability of undetectable PSA at 3^rd month postoperatively. Kaplan-Meier method estimated the probability of biochemical recurrence. Differences between the groups were compared by Log-rank test.

RESULTS

1478 patients were treated within the time span considered. 95 with 1 to 3 lymph-nodal metastases were extracted. After accounting for inclusion criteria, 23 patients with a median of 11 LN removed were included in the sPLND group (25th percentile); 23 patients with > 27 LN were included in ePLND group (75th percentile). Surgical time was longer for ePLND. Sixteen patients (69.6%) who underwent ePLND had undetectable PSA postoperatively. At multivariable analysis, the probability of undetectable PSA at 3^rd month was higher in patients who received an ePLND (HR=5.18; IC 95%=1.16-23.11; P=.03).

CONCLUSIONS

ePLND is more likely to predict undetectable PSA at third month after radical prostatectomy, irrespective of disease characteristics.

A machine learning-assisted decision-support model to better identify patients with prostate cancer requiring an extended pelvic lymph node dissection

OBJECTIVES

To develop a machine learning (ML)-assisted model to identify candidates for extended pelvic lymph node dissection (ePLND) in prostate cancer by integrating clinical, biopsy, and precisely defined magnetic resonance imaging (MRI) findings.

PATIENTS AND METHODS

In all, 248 patients treated with radical prostatectomy and ePLND or PLND were included. ML-assisted models were developed from 18 integrated features using logistic regression (LR), support vector machine (SVM), and random forests (RFs). The models were compared to the Memorial SloanKettering Cancer Center (MSKCC) nomogram using receiver operating characteristic-derived area under the curve (AUC) calibration plots and decision curve analysis (DCA).

RESULTS

A total of 59/248 (23.8%) lymph node invasions (LNIs) were identified at surgery. The predictive accuracy of the ML-based models, with (+) or without (-) MRI-reported LNI, yielded similar AUCs (RFs⁺ /RFs^- : 0.906/0.885; SVM⁺ /SVM^- : 0.891/0.868; LR⁺ /LR^- : 0.886/0.882) and were higher than the MSKCC nomogram (0.816; P < 0.001). The calibration of the MSKCC nomogram tended to underestimate LNI risk across the entire range of predicted probabilities compared to the ML-assisted models. The DCA showed that the ML-assisted models significantly improved risk prediction at a risk threshold of ≤80% compared to the MSKCC nomogram. If ePLNDs missed was controlled at <3%, both RFs⁺ and RFs^- resulted in a higher positive predictive value (51.4%/49.6% vs 40.3%), similar negative predictive value (97.2%/97.8% vs 97.2%), and higher number of ePLNDs spared (56.9%/54.4% vs 43.9%) compared to the MSKCC nomogram.

CONCLUSIONS

Our ML-based model, with a 5-15% cutoff, is superior to the MSKCC nomogram, sparing ≥50% of ePLNDs with a risk of missing <3% of LNIs.

Diagnostic accuracy of F18 flucholine PET/CT for preoperative lymph node staging in newly diagnosed prostate cancer patients; a systematic review and meta-analysis

OBJECTIVES

The purpose of the current study was to investiagte the diagnostic accuracy of ^F18 flucholine (FCH) positron emission tomography/CT (PET/CT) for pre-operative lymph node (LN) staging in newly diagnosed prostate cancer (PCa) patients using meta-analysis.

METHODS

PubMed and Embase from the earliest available date of indexing through December 31, 2018, were searched for studies evaluating the diagnostic performance of ^F18 FCH PET/CT for preoperative LN staging in newly diagnosed PCa. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR + and LR-), and constructed summary receiver operating characteristic curves.

RESULTS

Across seven studies (627 patients), the pooled sensitivity was 0.57 [95% confidence interval (CI) (0.42-0.70)] and a pooled specificity of 0.94 [95% CI (0.89-0.97)]. Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 10.2 (95% CI; 5.0-21.0) and negative likelihood ratio (LR-) of 0.46 (95% CI; 0.33-0.64). The pooled diagnostic odds ratio was 22 (95% CI; 9-54).

CONCLUSIONS

^F18 FCH PET/CT shows a low sensitivity and high specificity for the detection of metastatic LNs in patients with newly diagnosed PCa. Also, ^F18 FCH PET/CT is only useful for confirmation of LN metastasis (when positive) in PCa patients.

ADVANCES IN KNOWLEDGE

^F18 FCH PET/CT demonstrates low sensitivity but high specificity for diagnosis of metastatic LNs in patients with newly diagnosed PCa. Also, ^F18 FCH PET/CT is only useful for confirmation of LN metastasis (when positive) in PCa patients.

Combined analysis of CRMP4 methylation levels and CAPRA-S score predicts metastasis and outcomes in prostate cancer patients

The present study analyzed the predictive value of combined analysis of collapsin response mediator protein 4 (CRMP4) methylation levels and the Cancer of the Prostate Risk Assessment (CAPRA-S) Postsurgical score of patients who required adjuvant hormone therapy (AHT) after radical prostatectomy (RP). We retrospectively analyzed 305 patients with prostate cancer (PCa) who received RP and subsequent androgen deprivation therapy (ADT). Two hundred and thirty patients with clinically high-risk PCa underwent immediate ADT, and 75 patients with intermediate risk PCa underwent deferred ADT. CRMP4 methylation levels in biopsies were determined, and CAPRA-S scores were calculated. In the deferred ADT group, the values of the hazard ratios for tumor progression and cancer-specific mortality (CSM) in patients with ≥15% CRMP4 methylation were 6.81 (95% CI: 2.34–19.80) and 12.83 (95% CI: 2.16–26.10), respectively. Receiver-operating characteristic curve analysis indicated that CRMP4 methylation levels ≥15% served as a significant prognostic marker of tumor progression and CSM. In the immediate ADT group, CAPRA-S scores ≥6 and CRMP4 methylation levels ≥15% were independent predictors of these outcomes (uni- and multi-variable Cox regression analyses). The differences in the 5-year progression-free survival between each combination were statistically significant. Combining CAPRA-S score and CRMP4 methylation levels improved the area under the curve compared with the CRMP4 or CAPRA-S model. Therefore, CRMP4 methylation levels ≥15% were significantly associated with a poor prognosis and their combination with CAPRA-S score accurately predicted tumor progression and metastasis for patients requiring AHT after RP.

Oligometastatic Prostate Cancer: A Shrinking Subset or an Opportunity for Cure?

Oligometastatic prostate cancer (OMPC), generally defined by presence of five or fewer metastatic sites on imaging, represents a transitional state between localized and widespread metastatic disease and encompasses a wide spectrum of disease biologies and clinical behaviors. A collaborative effort is ongoing to determine the genomics of OMPC. The prevalence of OMPC varies significantly in the literature and is likely to change further as substantial improvements in imaging improve our ability to reclassify a subset of patients with biochemical recurrence by conventional imaging as OMPC and another subset from OMPC to polymetastatic disease. The mainstay of OMPC treatment remains systemic therapy, either with androgen-deprivation therapy (ADT) alone or in combination with other agents (docetaxel, abiraterone, etc.). Focal therapies, including resection or radiotherapy (RT), to the primary tumor have demonstrated an improvement in outcomes, including failure-free survival in several retrospective studies. RT to the prostate has specifically demonstrated an overall survival (OS) advantage in patients with low-volume disease in a clinical trial. Improvement in outcomes has been observed with focal therapies for retroperitoneal and more distant metastatic sites in retrospective studies. Advancements in our understanding of the biology, imaging modalities, and treatments may allow for aggressive multimodality therapies in an effort to obtain deeper responses and, potentially, cures for selected patients with OMPC with favorable clinicopathologic characteristics. Participation in clinical trials or institutional registries is strongly encouraged for patients with OMPC who opt for an aggressive multimodality approach.

Current controversies on the role of lymphadenectomy for prostate cancer

Lymph node dissection is part of the standard treatment protocol for various cancers, but its role in prostate cancer has been debatable for some time. Pelvic lymphadenectomy has been shown to better help stage prostate cancer patients, but has yet to be definitively proven to be of any benefit for survival. Various templates for lymph node dissections exist, and though some national guidelines have endorsed an extended pelvic node dissection, the choice of template is still controversial. Pelvic lymphadenectomy may lead to a slightly higher rate complications and operative time, and their use must be judiciously applied to patients with a high enough risk of lymph node involvement. We present a comprehensive review of the literature regarding the benefits and harms of lymph node dissection in prostate cancer.

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.

Effectiveness of extended pelvic lymphadenectomy in the survival of prostate cancer: a systematic review and meta-analysis

Introduction

To determine the effectiveness and safety of extended pelvic lymphadenectomy compared with standard lymphadenectomy in the overall, cancer-specific survival and biochemical recurrence-free survival of patients with localized prostate cancer who underwent radical prostatectomy.

Material and methods

Clinical trials and cohort studies were included without language restrictions with the following participants: men older than 40 years of age diagnosed with localized prostate cancer who received radical prostatectomy plus pelvic lymphadenectomy. Standard vs. extended pelvic lymphadenectomy were compared. The primary outcomes were overall and cancer-specific survival. A search strategy in MEDLINE, EMBASE, CENTRAL, LILACS, and other databases was conducted to obtain published and unpublished literature. The risk of bias was evaluated with the Cochrane Collaboration tool. The statistical analysis was performed in STATA 14.

Results

Six studies were included, of which only one was experimental; the other studies were cohort studies. The surgical technique was robot-assisted in three studies. Two studies only had information concerning the adverse effects. It was not possible to include one clinical trial that met the criteria because an erratum was published in which falsification of the experimental data was proven. There was a biochemical recurrence-free survival hazard ratio (HR) = 0.62 and a 95% confidence interval (CI) (0.36 to 0.87).

Conclusions

According to current literature, a mild difference was evident favoring the extended lymphadenectomy in biochemical recurrence-free survival. Additionally, there was no evidence to draw a conclusion regarding the overall survival since we did not find any studies concerning this outcome.

Imaging modalities in synchronous oligometastatic prostate cancer

Purpose

Along with a number of other malignancies, the term “oligometastatic” prostate cancer has recently emerged. It represents an attempt to define a subtype of cancer with a limited metastatic load that might perform more favorably than a distinctly disseminated disease, or even one that may be managed in a potentially curative way. Since there is currently a knowledge gap of what imaging modalities should be utilized to classify patients as having this type of tumor, we aimed to shed light on the role of conventional and marker-based imaging in the setting of synchronous oligometastatic prostate cancer as well as summarize the available evidence for its clinical application.

Methods

A literature search on December 15th 2017 was conducted using the Pubmed database.

Results

Functional imaging techniques like ⁶⁸Ga PSMA. ⁶⁸Ga PSMA PET-CT has currently been shown the best detection rates for the assessment of nodal, bone and visceral metastases, especially for smaller lesions at low PSA levels.

Conclusions

Functional imaging helps detect low-burden disease metastatic patients. However, these imaging modalities are not available in every center and thus clinicians may be prone to prescribe systemic treatment rather than referring patients for cytoreductive treatments. We hope that the ongoing prospective trials will help guide clinicians in making a more personalized management of synchronous metastatic patients.

Treatment of Oligometastatic Hormone-Sensitive Prostate Cancer: A Comprehensive Review

With advancements in diagnostic techniques, including molecular and clinical imaging, that directly target cancer cells, oligometastatic prostate cancer (PCa) is being diagnosed in patients who were, in the past, considered to have localized disease. With accumulating evidence, there has been a paradigm shift in considering aggressive treatments targeted at both the primary tumor and metastatic lesions in an aim to avoid and delay the need for palliative treatments and, ultimately, to achieve survival benefits. However, many questions still remain unanswered regarding the understanding of oligometastatic PCa, from its definition to optimal treatment strategies for each individual. Limited retrospective studies have suggested that interventions, including local and/or metastasis-directed therapy using surgery and radiation therapy (RT), can improve survival outcomes with minimal risk of adverse effects. Such treatments have been shown to decrease the risks of subsequent palliative interventions and to delay the start of androgen-deprivation therapy. Nevertheless, available data are insufficient to draw a reliable conclusion regarding their effect on quality of life measures and overall survival. This comprehensive review overviews data from contemporary literature that have investigated treatments, including surgery and RT, for patients with oligometastatic PCa, namely pelvic lymph node positive disease and limited distant metastases, and summarizes ongoing trials that are evaluating the feasibility of aggressive multimodal treatments.

Evaluation of 99mTc-labeled PSMA-SPECT/CT imaging in prostate cancer patients who have undergone biochemical relapse

Using conventional imaging modalities, it is difficult to detect recurrent lesions in prostate cancer patients who have undergone biochemical relapse, especially in patients with low prostate-specific antigen (PSA) levels. We retrospectively reviewed the files of fifty patients with histopathologically confirmed prostate cancer who underwent ^99mTc-labeled prostate-specific membrane antigen (PSMA) single-photon emission computed tomography (SPECT)/computed tomography (CT), magnetic resonance imaging (MRI), and bone scan within a 30-day period. PSMA-SPECT/CT indicated metastatic lesions in 39 patients and had a higher detection rate (78.0%) than bone scan (34.0%) or MRI (40.0%). The diagnostic efficiency of PSMA-SPECT/CT imaging for bone and lymph node metastases (50.0% and 42.0%) was better than bone scan (34.0% and 0.0%) or MRI (24.0% and 20.0%). PSMA-SPECT/CT provided a higher detection rate at serum PSA levels of ≤1 ng ml⁻¹, 1–4 ng ml⁻¹, 4–10 ng ml⁻¹, and >10 ng ml⁻¹. No correlation was found between Gleason score, PSA level, and the tracer tumor/background ratio of metastatic lesions. With the aid of PSMA-SPECT/CT imaging, the therapeutic strategy was changed for 31 patients, and this may have enhanced their clinical outcome. In conclusion, PSMA-SPECT/CT imaging could detect more metastatic lesions and achieve a higher detection rate than conventional imaging modalities at different serum PSA levels in prostate cancer patients who had undergone biochemical relapse.

Radical Prostatectomy for High-risk Localized or Node-Positive Prostate Cancer: Removing the Primary

PURPOSE OF REVIEW

We reviewed the literature to determine what role, if any, radical prostatectomy should play in the treatment of high-risk and/or node-positive prostate cancer.

RECENT FINDINGS

The AUA, NCCN, and EAU all include radical prostatectomy as a treatment option for high-risk prostate cancer based on evidence that has shown improvements in biochemical-free and disease-specific survival. Lymph node-positive patients may also derive benefit from radical prostatectomy with lymph node dissection, however, only retrospective studies with high risk of selection bias have been published to date. High-risk prostate cancer is a heterogeneous disease representing a wide range of disease characteristics. Radical surgery, historically avoided in such patients, may now be considered a valid treatment option for select cases. The adverse effects of surgery using modern techniques lead to similar quality of life outcomes as radiation therapy, and treatment of the primary tumor is likely beneficial when compared to ADT alone.

Impact of local treatment on overall survival of patients with metastatic prostate cancer: systematic review and meta-analysis

Context

Currently, standard treatment of metastatic prostatic cancer (MPCa) is androgen-deprivation therapy (ADT). Recent studies suggested that local treatment of MPCa is related to increase of survival of those patients, as observed in other tumors.

Objective

To evaluate the impact of local treatment on overall survival and cancer specific survival in 3 and 5 years in patients with MPCa.

Materials and Methods

Systematic review and meta-analysis of population studies published at PubMed, Scielo, Lilacs, Cochrane and EMBASE databases until June 2016. Several large cohorts and Post-Roc studies were included, that evaluated patients with MPCa submitted to local treatment (LT) using radiotherapy (RDT), surgery (RP) or brachytherapy (BCT) or not submitted to local treatment (NLT).

Results

34.338 patients were analyzed in six included papers, 31.653 submitted to NLT and 2.685 to LT. Overall survival in three years was significantly higher in patients submitted to LT versus NLT (64.2% vs. 44.5%; RD 0.19, 95% CI, 0.17-0.21; p<0.00001; I²=0%), as well as in five years (51.9% vs. 23.6%; RD 0.30, 95% CI, 0.11-0.49; p<0.00001; I²=97%). Sensitive analysis according to type of local treatment showed that surgery (78.2% and 45.0%; RD 0.31, 95% CI, 0.26-0.35; p<0.00001; I²=50%) and radiotherapy (60.4% and 44.5%; RD 0.17, 95% CI, 0.12-0.22; p<0.00001; I²=67%) presented better outcomes.

Conclusion

LT using RDT, RP or BCT seems to significantly improve overall survival and cancer-specific survival of patients with metastatic prostatic cancer. Prospective and randomized studies must be performed in order to confirm our results.

The oncologic results of cryoablation in prostate cancer patients with bone metastases

OBJECTIVE

To explore the role of whole gland cryoablation plus ADT in prostate cancer (PCa) with bone metastases compared with ADT treatment alone in metastatic PCa.

METHODS

A total of 30 patients with biopsy-proven PCa with bone metastases underwent cryoablation and ADT treatment. The control group consisted of 30 men who were initially treated with ADT only and who were followed until progression, development of castration resistant PCa or death. Patients were pair matched for age, PSA level, clinical stage, preoperative biopsy Gleason score and bone metastases. Time to clinical progression, time to CRPC, cancer-specific survival and overall survival were analysed using descriptive statistical analysis.

RESULTS

Age at diagnosis, baseline PSA, biopsy Gleason score and ECOG status were comparable between the two groups. Prostate cryoablation was well tolerated and no serious complications occurred. At the last follow-up, patients in the cryoablation and ADT treatment group had a lower median PSA nadir (0.4 ng/ml vs. 0.8 ng/ml, p < 0.01) and longer time to CRPC (33 ± 0.9 mo vs. 22 ± 0.8 mo, p < 0.01). Further analyses detected the statistically significant benefits of cryoablation treatment not only in PFS (41 ± 1.4 mo vs. 22 ± 0.8 mo, p < 0.01), but also in CSS (52 ± 1.9 mo vs. 32 ± 2.4 mo, p ± 0.01) and OS (41 ± 1.5 mo vs. 28 ± 1.7 mo, p < 0.01). Moreover, there were fewer palliative procedures for local progression in the cryoablation group than the controls.

CONCLUSIONS

Cryoablation plus ADT might be a treatment option in the multimodality management of metastatic prostate cancer. Further investigations are warranted.

Extended pelvic lymph-node dissection and radiotherapy with curative intent in high-risk lymph-node-positive prostate cancer: a possible curative strategy?

OBJECTIVE

This study evaluated the outcome with a treatment strategy for high-risk prostate cancer (PCa) using extended pelvic lymph-node dissection (eLND) followed by external beam radiation therapy (EBRT) in lymph-node-positive (LNpos) and lymph-node-negative (LNneg) cases compared with the strategy with limited pelvic lymph-node dissection (lLND) and only giving EBRT to LNneg cases.

MATERIALS AND METHODS

From 2000 to 2006, 124 men with high-risk PCa underwent lLND and initiated androgen deprivation therapy (ADT) before planned EBRT. LNpos patients were excluded from EBRT following the SPCG-7 study strategy (group I). From 2007 to 2013, 111 patients underwent eLND and started ADT before EBRT, and LNneg and most LNpos patients received EBRT (group II). Using Kaplan-Meier plots and multivariable Cox regression, biochemical recurrence-free, metastasis-free, cancer-specific survival and overall survival were compared during a 10 year follow-up.

RESULTS

PSA progression-free survival rates after 2, 4, 6, 8 and 10 years were 78%, 66%, 52%, 45% and 41% in group I, and 88%, 83%, 78%, 69% and 69% in group II (p < 0.001), respectively. Group II had a lower risk of PSA progression [hazard ratio (HR) = 0.43, 95% confidence interval (CI) 0.27,0.69, p = 0.001], metastasis development (HR = 0.51, 95% CI 0.27,0.97, p = 0.040) and overall mortality (HR = 0.49, 95% CI 0.26,0.92, p = 0.027), but not of PCa-specific death (HR = 0.45, 95% CI 0.19,1.08, p = 0.074).

CONCLUSION

A treatment strategy for high-risk PCa with eLND combined with EBRT in LNneg and LNpos cases may improve outcome compared to a strategy with lLND and offering EBRT only to LNneg cases but ADT to LNpos cases.

Role of robot-assisted radical prostatectomy in locally advanced prostate cancer

Locally advanced prostate cancer is regarded as a very high-risk disease with a poor prognosis. Although there is no definitive consensus on the definition of locally advanced prostate cancer, radical prostatectomy for locally advanced prostate cancer as a primary treatment or part of a multimodal therapy has been reported. Robot-assisted radical prostatectomy is currently carried out even in high-risk prostate cancer because it provides optimal outcomes. However, limited studies have assessed the role of robot-assisted radical prostatectomy in patients with locally advanced prostate cancer. Herein, we summarize and review the current knowledge in terms of the definition and surgical indications of locally advanced prostate cancer, and the surgical procedure and perisurgical/oncological outcomes of robot-assisted radical prostatectomy and extended pelvic lymphadenectomy for locally advanced prostate cancer.

Local Therapy Improves Overall Survival in Patients With Newly Diagnosed Metastatic Prostate Cancer

BACKGROUND

The role of local therapy, in the form of radiation therapy (RT) or radical prostatectomy(RP), and its association on outcomes is not well established in patients with metastatic prostate cancer.

METHODS

Using the National Cancer Database (NCDB), we evaluated patterns of care and outcomes among patients diagnosed with metastatic prostate cancer from 2004 to 2013 treated with local therapy (RP, intensity-modulated radiation therapy [IMRT], or 2D/3D-conformal radiation therapy [CRT]). The association between local therapy, co-variates, and outcomes was assessed in a multivariable Cox proportional hazards model and Propensity score (PS) matching was performed to balance confounding factors. Survival was estimated using the Kaplan-Meier method.

RESULTS

Among the 1,208,180 patients in the NCDB with prostate cancer, 6,051 patients met the inclusion criteria. No local therapy was used in 5,224 patients, while 622 (10.3%), 52 (0.9%), 153 (2.5%) patients received RP, IMRT, and 2D/3D-CRT, respectively. Use of local therapy was associated with younger age (≤70), lower co-morbidity score, lower T-stage, Gleason score <8, node-negative status, private, and Medicare insurance, higher income quartile, and treatment at comprehensive or academic/research programs (P < 0.05). Five-year overall survival for patients receiving local therapy was 45.7% versus 17.1% for those not receiving local therapy (P < 0.01). In multivariate analysis, RP (HR = 0.51; 95%CI, 0.45-0.59, P < 0.01) and IMRT (HR = 0.47; 95%CI, 0.31-0.72, P < 0.01) were independently associated with superior overall survival. After PS-matching, the use of local therapy (RP or IMRT) remained significantly associated with overall survival (HR = 0.35; 95%CI, 0.30-0.41, P < 0.01).

CONCLUSIONS

The use of RP and IMRT, to treat the primary disease, was associated with improvements in overall survival for patients with metastatic prostate cancer. We have identified patient-specific variations in the use of local therapy that may be tested in subsequent prospective clinical trials to improve patient outcomes in this setting. Prostate 77: 559-572, 2017. © 2017 Wiley Periodicals, Inc.

North American Population-Based Validation of the National Comprehensive Cancer Network Practice Guideline Recommendation of Pelvic Lymphadenectomy in Contemporary Prostate Cancer

BACKGROUND

National Comprehensive Cancer Network (NCCN) guidelines recommend a pelvic lymph node dissection (PLND) in prostate cancer (PCa) patients treated with radical prostatectomy (RP) if a nomogram predicted risk of lymph node invasion (LNI) is ≥2%. We examined this and other thresholds, including nomogram validation.

METHODS

We examined records of 26,713 patients treated with RP and PLND between 2010 and 2013, within the Surveillance, Epidemiology, and End Results database. Nomogram thresholds of 2-5% were tested and external validation was performed.

RESULTS

LNI was recorded in 4.7% of patients. Nomogram accuracy was 80.4% and maintained minimum accuracy of 75.6% in subgroup analyses, according to age, race, and nodal yield >10. With the NCCN recommended 2% nomogram threshold, PLND could be avoided in 22.3% of patients at the expense of missing 3.0% of individuals with LNI. Alternative thresholds of 3%, 4%, and 5% yielded respective PLND avoidance rates of 60.4%, 71.0%, and 79.8% at the expense of missing 17.8%, 27.2%, and 36.6% of patients with LNI. NCCN cut-off recommendation was best satisfied with a threshold of <2.6%, at which PLND could be avoided in 13,234 patients (49.5%) versus missing 141 patients with LNI (11.2%).

CONCLUSION

NCCN LNI nomogram remains accurate in contemporary patients. However, the 2% threshold appears to be too strict, since only 22.3% of PLNDs can be avoided, instead of the stipulated 47.7%. The optimal 2.6% threshold allows a higher rate of PLND avoidance (49.5%), at the cost of 11.2% missed instances of LNI, as recommended by NCCN guidelines. PATIENT SUMMARY. External validation in contemporary SEER prostate cancer patients showed that the NCCN nomogram remains accurate for predicting lymph node invasion and seems to be optimal at an alternative 2.6% threshold, with best ratio of avoided pelvic lymph node dissections (49.5%) and missed LNIs (11.2%), as recommended by NCCN guideline. Prostate 77:542-548, 2017. © 2017 Wiley Periodicals, Inc.

Radical prostatectomy for locally advanced and metastatic prostate cancer

The management of advanced prostate cancer remains challenging. Traditionally, radical prostatectomy was discouraged in patients with locally advanced or node positive disease owing to the increased complication rate and treatment related morbidity. However, technical advances and refinements in surgical techniques have enabled the outcomes for patients with high risk prostate cancer to be improved. More recently, the concept of cytoreductive prostatectomy has been described where surgery (often Combined with an extended lymph node dissection) is performed in the setting of metastatic disease. Indirect evidence suggests an advantage using the cytoreductive approach. Hypothetical explanations for this observed benefit include decreased tumour burden, immune modulation, improved response to secondary treatment and avoidance of secondary complications attributable to local tumour growth. Nevertheless, prospective trials are required to investigate this further.

[When is surgical treatment indicated in metastatic prostate cancer and what is the scientific rationale?]

BACKGROUND

Recent improvements in imaging diagnostics has led to a rising incidence of oligometastatic prostate cancer and, most notably, an increasing incidence of nodal-only biochemical recurrences. In this clinical setting, systemic therapy is still the treatment of choice. However, there is increasing evidence for surgical approaches in this challenging clinical setting.

AIM OF THE STUDY

In this comprehensive review article, current evidence regarding surgical approaches of primary nodal metastases, nodal-only biochemical recurrence following radical prostatectomy, and osseous metastatic prostate cancer will be discussed.

RESULTS

If nodal metastasis is clinically suspected, a significant survival benefit was observed in retrospective studies if radical prostatectomy and extended pelvic lymphadenectomy was performed within a multimodal therapeutic setting. Salvage lymphadenectomy as a therapeutic option for nodal-only biochemical recurrence is clinically feasible and can postpone systemic therapy significantly. However, since most patients do not have a lasting PSA response, a survival benefit of this therapeutic approach is questionable based on current evidence. Regarding osseous metastatic prostate cancer, the surgical approach has an inferior position compared to conservative management and radiotherapy.

CONCLUSION

Evidence regarding a surgical approach towards oligometastatic prostate cancer is increasing. However, current evidence is mainly based on retrospective studies that were conducted in the pre-PSMA-PET/CT era.

Impact of Lymph Node Burden on Survival of High-risk Prostate Cancer Patients Following Radical Prostatectomy and Pelvic Lymph Node Dissection

AIM

To determine the impact of the extent of lymph node invasion (LNI) on long-term oncological outcomes after radical prostatectomy (RP).

MATERIAL AND METHODS

In this retrospective study, we examined the data of 1,249 high-risk, non-metastatic PCa patients treated with RP and pelvic lymph node dissection (PLND) between 1989 and 2011 at eight different tertiary institutions. We fitted univariate and multivariate Cox models to assess independent predictors of cancer-specific survival (CSS) and overall survival (OS). The number of positive lymph node (LN) was dichotomized according to the most informative cutoff predicting CSS. Kaplan-Meier curves assessed CSS and OS rates. Only patients with at least 10 LNs removed at PLND were included. This cutoff was chosen as a surrogate for a well performed PNLD.

RESULTS

Mean age was 65 years (median: 66, IQR 60-70). Positive surgical margins were present in 53.7% (n = 671). Final Gleason score (GS) was 2-6 in 12.7% (n = 158), 7 in 52% (n = 649), and 8-10 in 35.4% (n = 442). The median number of LNs removed during PLND was 15 (IQR 12-17). Of all patients, 1,128 (90.3%) had 0-3 positive LNs, while 126 (9.7%) had ≥4 positive LNs. Patients with 0-3 positive LNs had significantly better CSS outcome at 10-year follow-up compared to patients with ≥4 positive LNs (87 vs. 50%; p < 0.0001). Similar results were obtained for OS, with a 72 vs. 37% (p < 0.0001) survival at 10 years for patients with 0-3 vs. ≥4 positive LNs, respectively. At multivariate analysis, final GS of 8-10, salvage ADT therapy, and ≥4 (vs. <4) positive LNs were predictors of worse CSS and OS. Pathological stage pT4 was an additional predictor of worse CSS.

CONCLUSION

Four or more positive LNs, pathological stage pT4, and final GS of 8-10 represent independent predictors for worse CSS in patients with high-risk PCa. Primary tumor biology remains a strong driver of tumor progression and patients having ≥4 positive LNs could be considered an enriched patient group in which novel treatment strategies should be studied.

Prostate-specific membrane antigen positron emission tomography in prostate cancer: a step toward personalized medicine

PURPOSE OF REVIEW

Increasing attention is being given to personalized medicine in oncology, where therapies are tailored to the particular characteristics of the individual cancer patient. In recent years, there has been greater focus on prostate-specific membrane antigen (PSMA) in prostate cancer (PCa) as a target for imaging and therapy with radionuclides. This review highlights the recent advancements in PSMA positron emission tomography (PET) in PCa during the past year.

RECENT FINDINGS

Several reports on PSMA PET/computed tomography (CT) in PCa patients are demonstrating promising results, especially for detection of biochemical recurrence. F-PSMA PET/CT may be superior to Ga-PSMA PET/CT. The detection rate of PSMA PET is influenced by prostate-specific antigen level. PSMA PET/CT may have a higher detection rate than choline PET/CT. Only a few reports have been published on PSMA PET/magnetic resonance imaging (MRI), and this modality remains to be elucidated further.

SUMMARY

Molecular imaging with PSMA PET is paving the way for personalized medicine in PCa. However, large prospective clinical studies are needed to further evaluate the role of PSMA PET/CT and PET/MRI in the clinical workflow of PCa. PSMA is an excellent target for imaging and therapy with radionuclides, and the 'image and treat' strategy has the potential to become a milestone in the management of PCa patients.