Anatomical basis for pelvic lymphadenectomy in prostate cancer: results of an autopsy study and implications for the clinic

Preclinical evaluation of robotic-assisted sentinel lymph node fluorescence imaging

An ideal substance to provide convenient and accurate targeting for sentinel lymph node (SLN) mapping during robotic-assisted surgery has yet to be found. We used an animal model to determine the ability of the FireFly camera system to detect fluorescent SLNs after administration of a dual-labeled molecular imaging agent.

METHODS

We injected the footpads of New Zealand White rabbits with 1.7 or 8.4 nmol of tilmanocept labeled with (99m)Tc and a near-infrared fluorophore, IRDye800CW. One and 36 h after injection, popliteal lymph nodes, representing the SLNs, were dissected with the assistance of the FireFly camera system, a fluorescence-capable endoscopic imaging system. After excision of the paraaortic lymph nodes, which represented non-SLNs, we assayed all lymph nodes for radioactivity and fluorescence intensity.

RESULTS

Fluorescence within all popliteal lymph nodes was easily detected by the FireFly camera system. Fluorescence within the lymph channel could be imaged during the 1-h studies. When compared with the paraaortic lymph nodes, the popliteal lymph nodes retain greater than 95% of the radioactivity at both 1 and 36 h after injection. At both doses (1.7 and 8.4 nmol), the popliteal nodes had higher (P < 0.050) optical fluorescence intensity than the paraaortic nodes at the 1- and 36-h time points.

CONCLUSION

The FireFly camera system can easily detect tilmanocept labeled with a near-infrared fluorophore at least 36 h after administration. This ability will permit image acquisition and subsequent verification of fluorescence-labeled SLNs during robotic-assisted surgery.

Clinical nodal staging scores for prostate cancer: a proposal for preoperative risk assessment

BACKGROUND

Pelvic lymph node dissection in patients undergoing radical prostatectomy for clinically localised prostate cancer is not without morbidity and its therapeutical benefit is still a matter of debate. The objective of this study was to develop a model that allows preoperative determination of the minimum number of lymph nodes needed to be removed at radical prostatectomy to ensure true nodal status.

METHODS

We analysed data from 4770 patients treated with radical prostatectomy and pelvic lymph node dissection between 2000 and 2011 from eight academic centres. For external validation of our model, we used data from a cohort of 3595 patients who underwent an anatomically defined extended pelvic lymph node dissection. We estimated the sensitivity of pathological nodal staging using a beta-binomial model and developed a novel clinical (preoperative) nodal staging score (cNSS), which represents the probability that a patient has lymph node metastasis as a function of the number of examined nodes.

RESULTS

In the development and validation cohorts, the probability of missing a positive lymph node decreases with increase in the number of nodes examined. A 90% cNSS can be achieved in the development and validation cohorts by examining 1-6 nodes in cT1 and 6-8 nodes in cT2 tumours. With 11 nodes examined, patients in the development and validation cohorts achieved a cNSS of 90% and 80% with cT3 tumours, respectively.

CONCLUSIONS

Pelvic lymph node dissection is the only reliable technique to ensure accurate nodal staging in patients treated with radical prostatectomy for clinically localised prostate cancer. The minimum number of examined lymph nodes needed for accurate nodal staging may be predictable, being strongly dependent on prostate cancer characteristics at diagnosis.

High-risk prostate cancer-classification and therapy

Approximately 15% of patients with prostate cancer are diagnosed with high-risk disease. However, the current definitions of high-risk prostate cancer include a heterogeneous group of patients with a range of prognoses. Some have the potential to progress to a lethal phenotype that can be fatal, while others can be cured with treatment of the primary tumour alone. The optimal management of this patient subgroup is evolving. A refined classification scheme is needed to enable the early and accurate identification of high-risk disease so that more-effective treatment paradigms can be developed. We discuss several principles established from clinical trials, and highlight other questions that remain unanswered. This Review critically evaluates the existing literature focused on defining the high-risk population, the management of patients with high-risk prostate cancer, and future directions to optimize care.

Is there a relationship between the number of lymph nodes and disease parameters in patients who underwent retropubic prostatectomy

PURPOSE

We aimed to establish the relationship between lymph nodes (LNs) counts that were removed with standard pelvic lymph node dissection (sPLND) and different disease parameters in patients who underwent radical prostatectomy (RP).

MATERIALS AND METHODS

A total of 70 patients who underwent sPLND during RP were scanned retrospectively. The scanned parameters were levels of serum PSA, the total weight of the removed prostate, the amount as a percentage of the tumor in the prostate tissue, the stage of the tumor, the total Gleason score (GS) and the number of standard pelvic lymph nodes that were removed from both right and left sides.

RESULTS

The average age of the patients was 59 years. A positive correlation was found between the total GS and the number of lymph nodes; while this correlation was significant (p = 0.0038), there was no significant difference between lymph nodes counts and other scanned parameters. The average pelvic lymph node numbers of patients with GS of 6-7 and 8 were 10.4-11.5 and 13.2, respectively. Lymph nodes metastases were found in 3 (4.2 %) patients whose average pelvic lymph node number was 17.3.

CONCLUSION

The chance of cure or decreased recurrence is much more possible in patients who had received extended PLND or at least standard one, because of the removal of much more lymph node tissues that have a high probability of disseminating cancer cells. This position can especially be considered in patients with high GS.

Outcomes of radical cystectomy with extended lymphadenectomy alone in patients with lymph node-positive bladder cancer who are unfit for or who decline adjuvant chemotherapy

OBJECTIVE

To analyse the long-term outcomes of patients with lymph node (LN)-positive bladder cancer, who did not receive any adjuvant therapy after radical cystectomy (RC) and extended pelvic lymph node dissection (ePLND).

PATIENTS AND METHODS

We conducted a retrospective, combined cohort analysis based on two prospectively maintained cystectomy databases from the University of Southern California and the University of Bern. Eligible patients underwent RC with ePLND for cN0M0 disease but were found to have LN-positive disease. No patient had neoadjuvant therapy, and all had negative surgical margins. Kaplan-Meier plots were used to estimate recurrence-free survival (RFS) and overall survival (OS). Subgroup comparisons were performed using log-rank tests, and multivariable analysis was based on Cox proportional hazard models.

RESULTS

Of 521 patients with LN-positive disease, 251 (48%) never received adjuvant therapy. Although the pathological stage distribution was similar, the 251 patients who did not receive adjuvant therapy were older and had both fewer total and positive LNs than those who underwent adjuvant therapy. The median RFS for patients treated with RC alone was 1.6 years. Recurrences mainly occurred <2 years after RC, resulting in 5- and 10-year RFS rates of 32 and 26%, respectively. Pathological T stage, the total number of LNs and the number of positive LNs detected were independent predictors of RFS and OS.

CONCLUSIONS

In this study, 25% of patients with documented LN metastases who did not receive adjuvant therapy were cured with RC and ePLND; however, a few relapses may occur later than 3 years. Predictors of survival were pathological T stage, the number of total LNs and the number of positive LNs identified.

Prospective comparison of computed tomography, diffusion-weighted magnetic resonance imaging and [11C]choline positron emission tomography/computed tomography for preoperative lymph node staging in prostate cancer patients

PURPOSE

The aim of this study was to prospectively compare diffusion-weighted magnetic resonance imaging (DWI) and [(11)C]choline positron emission tomography/computed tomography (PET/CT) with computed tomography (CT) for preoperative lymph node (LN) staging in prostate cancer (PCa) patients.

METHODS

Between June 2010 and May 2012, CT, DWI and [(11)C]choline PET/CT were performed preoperatively in 33 intermediate- and high-risk PCa patients undergoing radical prostatectomy (RP) and extended pelvic lymph node dissection (ePLND) including obturator fossa and internal, external and common iliac fields. Patient- and field-based performance characteristics for all three imaging techniques based on histopathological results are reported. Imaging techniques were compared by means of the area under the curve (AUC).

RESULTS

LN metastases were detected in 92 of 1,012 (9%) LNs from 14 of 33 (42%) patients. On patient-based analysis, sensitivity, specificity and accuracy for CT were 57, 68 and 64%, respectively, for DWI were 57, 79 and 70%, respectively, and for [(11)C]choline PET/CT were 57, 90 and 76%, respectively. On field-based analysis, these numbers for CT were 47, 94 and 88%, respectively, for DWI were 56, 97 and 92%, respectively, and for [(11)C]choline PET/CT were 62, 96 and 92%, respectively. Neither DWI nor [(11)C]choline PET/CT performed significantly better than CT on pairwise comparison of patient- and field-based results.

CONCLUSION

All three imaging techniques exhibit a rather low sensitivity with less than two thirds of LN metastases being detected on patient- and field-based analysis. Overall diagnostic efficacy did not differ significantly between imaging techniques, whereas distinct performance characteristics, esp. patient-based specificity, were best for [(11)C]choline PET/CT followed by DWI and CT.

Detection of pelvic lymph node micrometastasis by real-time reverse transcriptase polymerase chain reaction in prostate cancer patients after hormonal therapy

OBJECTIVE

To determine the feasibility of prostatic-specific antigen (PSA) mRNA and prostatic-specific membrane antigen (PSMA) mRNA measurement in detection of pelvic lymph node (PLN) micrometastasis for prostate cancer (PCa) after hormonal therapy (HT).

METHODS

Fifty-four patients diagnosed as high risk localized PCa were given HT for 3 months before radical prostatectomy. Under bipedal lymphangiography, a needle was punctured into involved lymph nodes (LN) and aspirated lymphatic fluid was obtained preoperatively. The expression of PSA mRNA and PSMA mRNA in aspirated fluid was assessed by a fully quantitative real-time reverse transcriptase polymerase chain reaction (RT-PCR) and also in LN specimens from pelvic lymphadenectomy during prostatectomy.

RESULTS

Median follow-up was 36 months (range 18-58 months). Without histological evidence of PLN metastasis, twelve patients showed positive PSA and/or PSMA mRNA expressions and regarded as having micrometastases to PLNs. Biochemical recurrence (BCR) rate and interval between prostatectomy and BCR in patients with micrometastases (group B) were not significantly different to histologically proven PLN metastatic patients (group A) (58.3 vs. 83.3 %, P = 0.26; 10.9 vs. 9.2 months, P = 0.29, respectively), but significantly different to those with no PLN involvement (group C) (58.3 vs. 11.1 %, P = 0.002; 10.9 vs. 21.3 months, P < 0.001, respectively). Kaplan-Meier analysis showed both groups A and B had significantly lower non-BCR rate than group C (P < 0.001, P < 0.001, respectively).

CONCLUSIONS

For PCa patients receiving HT, measurement of PSA mRNA and PSMA mRNA in aspirated PLN fluid by real-time RT-PCR could effectively detect PLN micrometastases without surgical intervention.

Lymph node-positive bladder cancer: surgical, pathologic, molecular and prognostic aspects

The presence of lymphatic metastasis is associated with markedly worse prognosis in patients with bladder cancer, although surgical resection and chemotherapy can still provide long-term survival for selected patients. The prognostic stratification of patients with positive lymph nodes has been broadly discussed in the current literature and a more extensive pelvic lymph node dissection and thorough pathologic assessment has been advocated. It is clear that stratification using the tumor node metastasis staging system is insufficient to adequately discriminate prognosis between patients with different lymph node involvement. Lymph node density and extranodal extension have been extensively investigated and appear to influence the prognosis of these patients. Molecular markers have been developed to improve the diagnosis of micrometastatic disease, and new targeted therapies have shown promising preclinical results and are now being tested in different clinical scenarios.

Does increasing the nodal yield improve outcomes in contemporary patients without nodal metastasis undergoing radical prostatectomy?

OBJECTIVES

To determine if the number of lymph nodes (LNs) removed is an independent predictor of biochemical recurrence (BCR) in patients without LN metastases undergoing radical prostatectomy (RP).

MATERIAL AND METHODS

Retrospective analysis of 7,310 patients treated at 7 centers with RP and pelvic LN dissection for clinically localized prostate cancer between 2000 and 2011. Patients with LN metastases (n = 398) and other reasons (stated later in the article) (n = 372) were excluded, which left 6,540 patients for the final analyses.

RESULTS

Overall, median biopsy and RP Gleason score were both 7; median prostate specific antigen level was 6 ng/ml (interquartile range [IQR]: 5); and median number of LNs removed was 6 (IQR: 8). A total of 3,698 (57%), 2,064 (32%), and 508 (8%) patients had ≥ 6, ≥ 10, and ≥ 20 LNs removed, respectively. Patients with more LNs removed were older, had a higher prostate specific antigen level, had higher clinical and pathologic T stage, and had higher RP Gleason score (all P<0.002). Within a median follow-up of 21 (IQR: 16) months, more LNs removed was associated with an increased risk of BCR (continuous: P = 0.021; categorical: P = 0.014). In multivariable analyses that adjusted for the effects of standard clinicopathologic factors, none of the nodal stratifications predicted BCR.

CONCLUSIONS

The number of LNs did not have any prognostic significance in our contemporary cohort of patients with LN-negative prostate cancer. This suggests that the risk of missed clinically significant micrometastasis may be minimal in patients currently treated with RP and having a lower LN yield.

Pelvic lymph node dissection in the context of radical cystectomy: a thorough insight into the connection between patient, surgeon, pathologist and treating institution

Pelvic lymph node dissection (PLND) in patients with bladder cancer varies widely in extent, technique employed, and pathological workup of specimens. The present paper provides an overview of the existing evidence regarding the effectiveness of PLND and elucidates the interactions between patient, surgeon, pathologist, and treating institution as well as their cumulative impact on the final postoperative lymph node (LN) staging. Bladder cancer patients undergoing radical cystectomy with extended PLND appear to have better oncologic outcomes compared to patients undergoing radical cystectomy and limited PLND. Attempts have been made to define and assess the quality of PLND according to the number of lymph nodes identified. However, lymph node counts depend on multiple factors such as patient characteristics, surgical template, pathological workup, and institutional policies; hence, meticulous PLND within a defined and uniformly applied extended template appears to be a better assurance of quality than absolute lymph node counts. Nevertheless, the prognosis of the patients can be partially predicted with findings from the histopathological evaluation of the PLND specimen, such as the number of positive lymph nodes, extracapsular extension, and size of the largest LN metastases. Therefore, particular prognostic parameters should be addressed within the pathological report to guide the urologist in terms of patient counseling.

Left-right asymmetry in neck lymph nodes distribution in patients with bilateral laryngeal cancer

OBJECTIVE

We aimed to examine left-right asymmetry in involved and total neck lymph nodes distribution in patients with bilateral laryngeal cancer in the present study.

METHODS

Forty-six patients with bilateral laryngeal cancer was included the study. The oncologic database of our otorhinolaryngology department was used. The right and left lymph node with and without involvement by cancer cells counts were retrieved from pathological reports.

RESULTS

The numbers of both involved and total neck lymph nodes were significantly higher on right side than on left side for all neck levels in laryngeal malignancies.

CONCLUSIONS

The results of the present study suggest the existence of a left-right asymmetry in neck lymph node distribution and in the neck lymph node distribution involved by laryngeal cancer cells. The stronger cell-mediated immune activity in the left side of humans may be associated with the blocking of the metastatic invasion of cancer cells from laryngeal malignancies in the left body side.

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.

Characteristics of Pelvic Lymph Node Metastases in Prostatic Adenocarcinoma

Pelvic lymph node dissection (PLND) is currently the most accurate staging modality for lymph node metastases in prostate adenocarcinoma. There is no consensus on the optimal sampling method of PLND specimens among pathologists. This study analyzed the effectiveness of the submission of entire adipose tissue in 451 cases and its impact on total lymph node yield and detection of positive lymph nodes. The sizes of metastatic foci and positive lymph nodes in 83 cases were also studied. Submission of entire adipose tissue increased the lymph node yield and positive lymph node detection by 36.7 % and 1.99 %, respectively. Three cases had positive lymph nodes exclusively in adipose tissue. Of the patients examined, 68% had the largest positive lymph node, <1 cm. In conclusion, it was noted that metastases from prostate cancer were frequently small and seen within small lymph nodes. Submission of entire adipose tissue substantially increased the lymph node yield, but its impact on the detection of additional positive lymph nodes was low. Submission of the entire adipose tissue may be considered as an option in patients with high-risk factors for lymph node metastases.

[Lymphadenectomy for bladder cancer: current status and controversies]

Pelvic lymph node dissection is an integral part of the radical cystectomy procedure for patients with muscle-invasive bladder cancer. The optimal extent of the lymphadenectomy (LND) and mainly the proximal template boundary remain controversial issues. In view of the existing mapping studies and retrospective analyses, extended LND up to the mid-upper third of the common iliac vessels appears to provide further prognostic and therapeutic benefit and therefore should be defined as standard LND. This applies for all procedures irrespective of the choice of surgical approach (open surgery, minimally invasive approach). In this context total lymph node count is not a quality criterion because nodal yield is overly influenced by the individual patient's anatomy, surgical technique, template applied and pathological work-up. Consecutively, considerable inter-institutional differences result, which render any comparison impossible. Lymph node density is thought to be a superior prognostic factor, but it is similarly influenced by the above-mentioned factors. Concerning molecular techniques to improve the sensitivity of postoperative nodal staging further research is necessary. The two ongoing prospective randomized trials will potentially help to further define the optimal LND template.

Lymph node-positive prostate cancer: current issues, emerging technology and impact on clinical outcome

Lymph node metastasis in patients with prostate cancer indicates a poorer prognosis compared with patients without lymph node metastasis; however, some patients with node-positive disease have long-term survival. Many studies have attempted to discern what characteristics of lymph node metastasis are prognostically significant. These characteristics include nodal tumor volume, number of positive lymph nodes, lymph node density, extranodal extension, lymphovascular invasion and tumor dedifferentiation. Favorable characteristics of regional lymph node involvement included a smaller tumor size and smaller tumor volume. However, the current staging system for prostate cancer does not provide different subclassifications for patients with node-positive prostate cancer. In recent years numerous advanced technologies for the detection of lymph node metastasis have been developed, including molecular imaging techniques and the CellSearch Circulating Tumor Cell System. With the increased detection of patients with prostate cancer, emergence of new technology to identify lymph node metastasis and the number of radical prostatectomies being performed on the rise, subclassifying patients with lymph node-positive disease is imperative. Subclassification would provide a better picture of patient prognosis and allow for a better understanding of targeted therapies to treat patients with lymph node metastasis.

Standard lymph node dissection for bladder cancer: significant variability in the number of reported lymph nodes

PURPOSE

We compared the nodal yield after histopathological examination of extended bilateral pelvic lymph node dissection specimens for bladder cancer at 2 hospitals. Surgery at each hospital was done by the same 4 staff urologists using a standardized extended bilateral pelvic lymph node dissection template.

MATERIALS AND METHODS

All consecutive patients with bladder cancer who underwent extended bilateral pelvic lymph node dissection from January 1, 2007 to December 31, 2009 were included in this study. Specimens were sent for pathological evaluation in a minimum of 2 packages per side. At the 2 pathology departments specimens were processed according to institutional protocols.

RESULTS

A total of 174 patients with a mean age of 62.7 years were included in analysis. At hospital 1 a mean of 16 lymph nodes were found after dissection vs a mean of 28 reported at hospital 2 (p <0.001). No significant differences were found in the number of tumor positive lymph nodes (p = 0.65). Mean lymph node density at hospitals 1 and 2 was 9.3% and 3.9%, respectively (p = 0.056).

CONCLUSIONS

Despite equal anatomical clearance by the same experienced surgeons we report a statistically significant difference between 2 pathology departments where the number of lymph nodes was evaluated after extended bilateral pelvic lymph node dissection for bladder cancer. Unless standardized methods are agreed on by pathologists, the number of reported lymph nodes as an indicator of surgical quality and lymph node density as a prognostic factor should be used cautiously.

Sense and nonsense of an extended pelvic lymph node dissection in prostate cancer

Lymph node metastases associated with prostate cancer (PCa) has been shown to be a poor prognostic factor. The role of pelvic lymph node dissection (PLND) itself in relation to survival remains unclear, however. A Medline search was conducted to address this issue. The following conclusions were drawn. Only recently, improved survival due to completion of radical prostatectomy (RP) (compared to abandoning RP) in known or presumed lymph-node-positive patients has been shown. Lymph node sampling can only be considered representative if an adequate number of nodes is removed. While several authors have suggested that a therapeutic benefit in patients undergoing RP is not provided by PLND, the reliability of these studies is uncertain. Contrary to this, several studies have indicated the possibility of long-term survival even in the presence of limited lymph node metastases. The role and timing of initiation of adjuvant androgen deprivation therapy (ADT) in patients who have node-positive disease after RP is controversial. Recent studies suggest that delaying ADT may not adversely impact survival.

Pelvic lymphadenectomy in the treatment of invasive bladder cancer: literature review

The standard surgical treatment of invasive bladder cancer is the radical cystectomy and pelvic lymph node dissection (PLND). Up to one-third of patients with invasive bladder cancer have lymph node metastasis. Thus, PLND has important therapeutic and prognostic benefits. The number of lymph nodes that should be removed and the extent of the PLND are still a controversial issue. Recently, the trend of PLND increased toward more extended PLND. Several prognostic factors related to PLND were reported in the literature. In this paper, we will discuss the different PLND templates, number of lymph nodes that should be resected, lymph node density, lymphovascular invasion, tumor burden, extracapsular extension, and the aggregate lymph node metastasis diameter.

Role of pelvic lymph node dissection in prostate cancer treatment

Pelvic lymph node dissection (PLND) is the most accurate and reliable staging procedure for detecting lymph node invasion (LNI) in prostate cancer. Recently, [(11)C]-choline positron emission tomography imaging and magnetic resonance imaging with lymphotropic superpara-magnetic nanoparticles have shown potential for detecting LNI but are still under investigation. The risk of LNI in low-risk groups could be underestimated by use of the current nomograms, which rely on data collected from patients who underwent only limited PLND. Extended PLND (ePLND) shows higher lymph node yield, which leads to the removal of more positive nodes and fewer missed positive nodes. It may be possible to refrain from performing PLND on low-risk patients with a prostate-specific antigen value <10 ng/ml and a biopsy Gleason score ≤6, but the risk of biopsy-related understaging should be kept in mind. Theoretically, meticulous ePLND may also impact prostate cancer survival by clearing low-volume diseases and occult micrometastasis even in pN0. The therapeutic role of PLND in prostate cancer patients is still an open question, especially in individuals with low-risk disease. Patients with intermediate- to high-risk disease are more likely to benefit from ePLND.

The role of lymph node dissection in the management of prostate cancer

Lymph node dissection is a standard procedure for treatment of several cancers, but its role in prostate cancer (PCa) as an adjunct of radical prostatectomy is still debated and controversial. Pelvic lymph node dissection (PLND) is currently the most reliable means of diagnosis of lymph node metastases. A uniform PLND surgical template cannot be determined, but recent evidence shows that extended PLND provides more lymph nodes, increases the accuracy of detection of lymph node metastases, and affects decision making with regard to adjuvant therapy. Several nomograms have been developed to predict those who may need more extensive PLND, while sparing the rest. Importantly, no prospective data indicate that extension of PLND improves cancer control or benefits survival. A well designed prospective randomized study is needed to resolve these issues. We present a comprehensive literature review and critical discussion of the diagnostic and therapeutic role of PLND in PCa.

Association between the number of dissected lymph nodes during pelvic lymphadenectomy and cancer-specific survival in patients with lymph node-negative urothelial carcinoma of the bladder undergoing radical cystectomy

BACKGROUND

A larger number of dissected lymph nodes (LN) during pelvic lymphadenectomy in patients with muscle-invasive transitional-cell carcinoma of the bladder treated by radical cystectomy (RC) is crucial for exact tumor staging and is associated with a positive oncological outcome.

METHODS

Clinical and pathological records of 1291 patients undergoing RC due to LN-negative transitional-cell carcinoma of the bladder were summarized and evaluated in a multi-institutional database. The number of removed LNs and the presence or absence of lymphovascular invasion were assessed. On the basis of multivariate Cox regression analyses, a threshold number of removed LNs was defined that exerted an independent influence on cancer-specific survival (CSS).

RESULTS

In multivariate Cox regression models for different numbers of removed LNs, a statistically significant enhancement of CSS could be demonstrated for a LN count of 16. Furthermore, the integration of the dichotomized LN count of 16 resulted in a statistically significantly enhanced predictive ability of the model for CSS. Patients with <16 and ≥16 removed LNs showed CSS rates after 5 years of 72% and 83%, respectively (P = 0.01). In addition, age, sex, pT stage, and lymphovascular invasion had independent influences on CSS in every Cox regression model.

CONCLUSIONS

In patients undergoing RC, removal of a higher LN count is associated with an improved oncological outcome. The information resulting from an assessment of lymphovascular invasion and an extended lymphadenectomy is critical for stratification of risk groups and identification of patients who might benefit from adjuvant treatment.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 4: seminal vesicles and lymph nodes

The 2009 International Society of Urological Pathology Consensus Conference in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to the infiltration of tumor into the seminal vesicles and regional lymph nodes were coordinated by working group 4. There was a consensus that complete blocking of the seminal vesicles was not necessary, although sampling of the junction of the seminal vesicles and prostate was mandatory. There was consensus that sampling of the vas deferens margins was not obligatory. There was also consensus that muscular wall invasion of the extraprostatic seminal vesicle only should be regarded as seminal vesicle invasion. Categorization into types of seminal vesicle spread was agreed by consensus to be not necessary. For examination of lymph nodes, there was consensus that special techniques such as frozen sectioning were of use only in high-risk cases. There was no consensus on the optimal sampling method for pelvic lymph node dissection specimens, although there was consensus that all lymph nodes should be completely blocked as a minimum. There was also a consensus that a count of the number of lymph nodes harvested should be attempted. In view of recent evidence, there was consensus that the diameter of the largest lymph node metastasis should be measured. These consensus decisions will hopefully clarify the difficult areas of pathological assessment in radical prostatectomy evaluation and improve the concordance of research series to allow more accurate assessment of patient prognosis.

How can we predict lymphorrhoea and clinically significant lymphocoeles after radical prostatectomy and pelvic lymphadenectomy? Clinical implications

OBJECTIVE

• To identify clinical and pathological variables that may help clinicians in predicting, preventing and managing lymphorrhoea and clinically significant lymphocoeles (CSL), which are reported complications after pelvic lymphadenectomy (PLND) and retropubic radical prostatectomy (RRP).

PATIENTS AND METHODS

• We prospectively analysed 552 consecutive men with prostate cancer who underwent RRP and PLND (2006-2008). • All patients had detailed clinical and pathological data prospectively recorded in an electronic database. Drains were removed when the amount of lymph was < 20 mL in the previous 24 h. A CSL was defined as the presence of a symptomatic lymphocoele requiring treatment. Lymphorrhoea was defined as the total amount of lymph drained by the drains until their removal. • Univariable and multivariable logistic regression models were used to test the association between all the predictors (age, body mass index, American Society of Anesthesiologists score, prostate volume, clinical stage, number of LNs removed, surgeon, pathological T and N stage) and the presence of CSL. • Univariable and multivariable linear regression models were also used to test the association between the available predictors and lymphorrhoea.

RESULTS

• The median (range) number of LNs removed was 20 (1-63). Both linear and logistic multivariable regression analysis showed that the number of removed LNs and age were the only two statistically significant predictors of total amount of lymphorrhoea and CSL after RRP and PLND (both P < 0.01). • Specifically, the risk of developing a CSL increased by 5% for every LN removed. Similarly, every year of age increased the risk of having CSL by 5%. • The most informative thresholds for predicting CSL were 65 years of age and 20 LNs removed. • External iliac lymphadenectomy resulted in a higher associated risk of lymphorrhoea and CLS relative to obturator LN removal (P= 0.001 vs P= 0.1, respectively).

CONCLUSIONS

• There was a positive association between the number of LNs removed and age at RRP with the amount of lymphorrhoea and the risk of developing a CSL. • The most informative thresholds in predicting CSL were 65 years of age and 20 LNs removed. External iliac lymphadenectomy resulted in a higher risk of lymphorrhoea and CLS relative to obturator LN removal.