Intravesical tumor involvement of the trigone is associated with nodal metastasis in patients undergoing radical cystectomy

Electronic Documentation of Intraoperative Observation of Cystoscopic Procedures Using the cMDX Information System

PURPOSE

Accurate documentation of lesions during transurethral resection of bladder tumors (TURBT) is essential for precise diagnosis, treatment planning, and follow-up care. However, optimizing schematic documentation techniques for bladder lesions has received limited attention.

MATERIALS AND METHODS

This prospective observational study used a cMDX-based documentation system that facilitates graphical representation, a lesion-specific questionnaire, and heatmap analysis with a posterization effect. We designed a graphical scheme for bladder covering bladder landmarks to visualize anatomic features and to document the lesion location. The lesion-specific questionnaire was integrated for comprehensive lesion characterization. Finally, spatial analyses were applied to investigate the anatomic distribution patterns of bladder lesions.

RESULTS

A total of 97 TURBT cases conducted between 2021 and 2023 were included, identifying 176 lesions. The lesions were distributed in different bladder areas with varying frequencies. The distribution pattern, sorted by frequency, was observed in the following areas: posterior, trigone, lateral right and anterior, and lateral left and dome. Suspicious levels were assigned to the lesions, mostly categorized either as indeterminate or moderate. Lesion size analysis revealed that most lesions fell between 5 and 29 mm.

CONCLUSION

The study highlights the potential of schematic documentation techniques for informed decision making, quality assessment, primary research, and secondary data utilization of intraoperative data in the context of TURBT. Integrating cMDX and heatmap analysis provides valuable insights into lesion distribution and characteristics.

European Association of Urology Guidelines on Muscle-invasive and Metastatic Bladder Cancer: Summary of the 2023 Guidelines

CONTEXT

We present an overview of the updated 2023 European Association of Urology (EAU) guidelines for muscle-invasive and metastatic bladder cancer (MMIBC).

OBJECTIVE

To provide practical evidence-based recommendations and consensus statements on the clinical management of MMIBC with a focus on diagnosis and treatment.

EVIDENCE ACQUISITION

A broad and comprehensive scoping exercise covering all areas of the MMIBC guidelines has been performed annually since 2017. Searches cover the Medline, EMBASE, and Cochrane Libraries databases for yearly guideline updates. A level of evidence and strength of recommendation are assigned. The evidence cutoff date for the 2023 MIBC guidelines was May 4, 2022.

EVIDENCE SYNTHESIS

Patients should be counselled regarding risk factors for bladder cancer. Pathologists should describe tumour and lymph nodes in detail, including the presence of histological subtypes. The importance of the presence or absence of urothelial carcinoma (UC) in the prostatic urethra is emphasised. Magnetic resonance imaging (MRI) of the bladder is superior to computed tomography (CT) for disease staging, specifically in differentiating T1 from T2 disease, and may lead to a change in treatment approach in patients at high risk of an invasive tumour. Imaging of the upper urinary tract, lymph nodes, and distant metastasis is performed with CT or MRI; the additional value of flurodeoxyglucose positron emission tomography/CT still needs to be determined. Frail and comorbid patients should be evaluated by a multidisciplinary team. Postoperative histology remains the most important prognostic variable, while circulating tumour DNA appears to be an interesting predictive marker. Neoadjuvant systemic therapy remains cisplatin-based. In motivated and selected women and men, sexual organ-preserving cystectomy results in better functional outcomes without compromising oncological outcomes. Robotic and open cystectomy have comparable outcomes and should be combined with (extended) lymph node dissection. The diversion type is an individual choice after taking patient and tumour characteristics into account. Radical cystectomy remains a highly complex procedure with considerable morbidity and risk of mortality, although lower rates are observed for higher hospital volumes (>20 cases/yr). With proper patient selection, trimodal therapy (chemoradiation) has comparable outcomes to radical cystectomy. Adjuvant chemotherapy after surgery improves disease-specific survival and overall survival (OS) in patients with high-risk disease who did not receive neoadjuvant treatment, and is strongly recommended. There is a weak recommendation for adjuvant nivolumab, as OS data are not yet available. Health-related quality of life should be assessed using validated questionnaires at baseline and after treatment. Surveillance is needed to monitor for recurrent cancer and functional outcomes. Recurrences detected on follow-up seem to have better prognosis than symptomatic recurrences.

CONCLUSIONS

This summary of the 2023 EAU guidelines provides updated information on the diagnosis and treatment of MMIBC for incorporation into clinical practice.

PATIENT SUMMARY

The European Association of Urology guidelines panel on muscle-invasive and metastatic bladder cancer has released an updated version of the guideline containing information on diagnosis and treatment of this disease. Recommendations are based on studies published up to May 4, 2022. Surgical removal of the bladder and bladder preservation are discussed, as well as updates on the use of chemotherapy and immunotherapy in localised and metastatic disease.

Effects of intravenous chemotherapy after TURBT for high-risk nonmuscle invasive bladder cancer: results of a retrospective study

PURPOSE

This study compared the efficacy and safety of intravenous chemotherapy combined with intravesical chemotherapy versus intravesical chemotherapy alone for high-risk nonmuscle invasive bladder cancer (HRNMIBC) patients after transurethral resection of the bladder tumor (TURBT) surgery.

METHODS

A retrospective analysis was performed on 349 HRNMIBC cases admitted to TangDu hospital between January 2014 and June 2019. After TURBT, 262 patients received intravesical chemotherapy alone, whereas 87 patients underwent intravesical chemotherapy in combination with intravenous chemotherapy. The recurrence rate and progression rate were assessed by Chi-square test, the prognostic factors for tumor recurrence were predicted by univariable and multivariable Cox hazards analyses, recurrence-free survival (RFS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method.

RESULTS

In this study, the recurrence rate was 24.7% (19/77) in the intravenous chemotherapy combined group and 41.6% (102/245) in the intravesical chemotherapy group, while the progression rate was 6.5% (5/77) and 14.3% (35/245) in the two groups respectively. The two groups differed significantly in recurrence rate (p = 0.007) while the progression rate did not show a significant difference (p = 0.071). Multivariable analyses revealed that additional intravenous chemotherapy treatment was an independent prognostic factor for tumor recurrence in the cohort (hazard ratio [HR], 0.495, 95% confidence interval [CI], 0.275-0.892, p = 0.019). Kaplan-Meier curves showed significant differences in RFS and PFS between the two groups, with a log-rank P value of p < 0.005 and p = 0.045, respectively. Grade 3/4 toxicity was reported in 2 of 77 patients in the intravenous chemotherapy combined group, including nausea/vomiting 1.3% (1/77) and hypoleukemia 1.3% (1/77).

CONCLUSION

Intravenous chemotherapy of gemcitabine and cisplatin combined with intravesical chemotherapy after TURBT can effectively reduce the postoperative recurrence rate, most toxicities were minor and reversible, and it may be considered as a new choice for HRNMIBC patients.

Development and external validation of a novel nomogram model for predicting postoperative recurrence-free survival in non-muscle-invasive bladder cancer

Background

Transurethral resection of the bladder tumor with or without adjuvant intravesical instillation (IVI) has been the standard treatment for non-muscle-invasive bladder cancer (NMIBC), whereas a high percentage of patients still experience local tumor recurrence and disease progression after receiving the standard treatment modalities. Unfortunately, current relevant prediction models for determining the recurrent and progression risk of NMIBC patients are far from impeccable.

Methods

Clinicopathological characteristics and follow-up information were retrospectively collected from two tertiary medical centers between October 2018 and June 2021. The least absolute shrinkage and selection operator (LASSO) and Cox regression analysis were used to screen potential risk factors affecting recurrence-free survival (RFS) of patients. A nomogram model was established, and the patients were risk-stratified based on the model scores. Both internal and external validation were performed by sampling the model with 1,000 bootstrap resamples.

Results

The study included 299 patient data obtained from the Affiliated Hospital of Xuzhou Medical University and 117 patient data obtained from the First Affiliated Hospital of Guangxi Medical University. Univariate regression analysis suggested that urine red blood cell count and different tumor invasion locations might be potential predictors of RFS. LASSO-Cox regression confirmed that prior recurrence status, times of IVI, and systemic immune-inflammation index (SII) were independent factors for predicting RFS. The area under the curve for predicting 1-, 2-, and 3-year RFS was 0.835, 0.833, and 0.871, respectively. Based on the risk stratification, patients at high risk of recurrence and progression could be accurately identified. A user-friendly risk calculator based on the model is deposited at https://dl0710.shinyapps.io/nmibc_rfs/.

Conclusion

Internal and external validation analyses showed that our model had excellent predictive discriminatory ability and stability. The risk calculator can be used for individualized assessment of survival risk in NMIBC patients and can assist in guiding clinical decision-making.

Imaging Tips and Tricks in Management of Renal and Urothelial Malignancies

Management of urological malignancies has evolved significantly with continually changing guidelines and treatment options which demand more centralized involvement of radiology than ever before.

Radiologists play a pivotal role in interpreting complex cancer scans and guiding clinical teams toward the best management options in the light of clinical profile. Management of complex uro-oncology cases is often discussed in multidisciplinary meetings which are essential checkpoints to evaluate an overall picture and formulate optimal treatment plans.

The aim of this article is to provide a radiological perspective with practical guidance to fellow radiologists participating in uro-oncology multidisciplinary meetings based on commonly encountered case scenarios, updated guidelines, and cancer pathways.

Crucial imaging tips with regards to renal and urinary tract cancers, upon which therapeutic decisions are made, have been condensed in this article after reviewing several complex cases from urology multidisciplinary meetings and European Association of Urology guidelines.

Outline of various diagnostic and management strategies, key staging features, surveillance guidelines, and, above all, what the onco-urologists want to know from radiologists have been succinctly discussed in this article.

Prognostic impact of insulin‐like growth factor‐I and its binding proteins, insulin‐like growth factor‐I binding protein‐2 and ‐3, on adverse histopathological features and survival outcomes after radical cystectomy

Objectives

Insulin‐like growth factor‐I and its binding proteins are involved in cancer development, progression, and metastasis. In urothelial carcinoma, the impact of this pathway is still poorly investigated. The present large cohort study aimed to evaluate the association of preoperative circulating levels of insulin‐like growth factor‐I, insulin‐like growth factor‐I binding protein‐2 and ‐3 on outcomes after radical cystectomy.

Methods

A retrospective cohort study of the plasma specimens from 1036 consecutive urothelial carcinoma patients who were treated with radical cystectomy. The primary and secondary outcomes were adverse histopathological features and survival outcomes. Binominal logistic regression and multivariable Cox regression analyses were performed to assess the association of plasma levels of insulin‐like growth factor‐I, insulin‐like growth factor‐I binding protein‐2 and ‐3 with outcomes.

Results

On multivariable analysis adjusting for the effects of preoperative variables, lower insulin‐like growth factor‐I binding protein‐2 levels were associated with an increased risk of lymph node metastasis and (any non‐organ confined disease) any non‐organ confined disease. Insulin‐like growth factor‐I binding protein‐3 levels were also inversely independently associated with lymph node metastasis. Receiver operating characteristic curve analysis showed that the addition of insulin‐like growth factor‐I binding proteins biomarkers to a reference model significantly improved the discriminating ability for the prediction of lymph node metastasis (+10.0%, P < 0.001). On multivariable Cox regression models, lower levels of both insulin‐like growth factor‐I binding protein‐2 and ‐3 plasma levels were associated with recurrence‐free survival, cancer‐specific survival, and overall survival. insulin‐like growth factor‐I binding protein‐2 and ‐3 levels and improved the discrimination of a standard reference model for the prediction of recurrence‐free survival, cancer‐specific survival, and overall survival (+4.9%, 4.9%, 2.3%, respectively).

Conclusions

Preoperative insulin‐like growth factor‐I binding protein‐2 and ‐3 are significantly associated with features of biologically and clinically aggressive urothelial carcinoma. These biomarkers improved prognostic urothelial carcinoma models.

Prognostic significance of bladder neck involvement in non-muscle-invasive bladder cancer: A SEER database analysis with 19,919 patients

PURPOSE

To study prognostic values of bladder neck involvement (BNI) and survival outcomes in non-muscle-invasive bladder cancer (NMIBC).

METHOD AND MATERIALS

The national Surveillance, Epidemiology, and End Results database (2004-2015) was applied to gain further insight into the prognostic values of BNI and 19,919 patients diagnosed with NMIBC were included in our study. We used the Kaplan-Meier method with the log-rank test and subgroup analyses to evaluate cancer-specific survival (CSS) and overall survival (OS). In addition, the multivariable Cox proportional hazard model and propensity score matching (PSM) were utilized.

RESULTS

In all, 3446 patients with BNI and 16,473 patients with sites except for bladder neck were enrolled in our study. Compared with other sites, a tendency toward a higher proportion of higher grade (p < 0.001), bigger tumor size (p < 0.001), and more patients with T1 and Tis stage (p < 0.001) was seen in BNI group. After 1:1 PSM, 3425 matched pairs were selected. Under the survival analyses, the BNI group had a lower survival probability in both OS (p = 0.0056) and CSS analyses (p < 0.0001) in NMIBC patients. However, in the subgroup analysis, only observed in the Ta and T1 stage in terms of CSS (all p < 0.05), and patients with Tis stage failed to show statistical survival differences (p > 0.05). In addition, subgroups stratified by tumor size and grade all revealed poor prognosis of BNI in NMIBC patients. Moreover, better survival outcomes of OS were observed in BNI patients who received radical cystectomy (p = 0.02) or chemotherapy (p < 0.001) multivariable Cox regression after PSM revealed that the BNI group had a higher risk of overall mortality (OM) (BNI vs. other sites hazards ratios [HR]: 1.127, 95% CI: 1.154-1.437, p < 0.001) and cancer-specific mortality (CSM) (BNI vs. other sites HR: 1.127, 95% CI: 1.039-1.223, p < 0.001), while before PSM, similar situations were only existed in CSM (BNI vs. other sites HR: 1.288, 95% CI: 1.154-1.437, p < 0.001).

CONCLUSIONS

The prognosis of BNI was poorer than that of the other sites. BNI was an independent risk factor for OM and CSM in patients with NMIBC, especially for those with Ta or T1 stage.

MRI of Bladder Cancer: Local and Nodal Staging

Accurate staging of bladder cancer (BC) is critical, with local tumor staging directly influencing management decisions and affecting prognosis. However, clinical staging based on clinical examination, including cystoscopy and transurethral resection of bladder tumor (TURBT), often understages patients compared to final pathology at radical cystectomy and lymph node (LN) dissection, mainly due to underestimation of the depth of local invasion and the presence of LN metastasis. MRI has now become established as the modality of choice for the local staging of BC and can be additionally utilized for the assessment of regional LN involvement and tumor spread to the pelvic bones and upper urinary tract (UUT). The recent development of the Vesical Imaging-Reporting and Data System (VI-RADS) recommendations has led to further improvements in bladder MRI, enabling standardization of image acquisition and reporting. Multiparametric magnetic resonance imaging (mpMRI) incorporating morphological and functional imaging has been proven to further improve the accuracy of primary and recurrent tumor detection and local staging, and has shown promise in predicting tumor aggressiveness and monitoring response to therapy. These sequences can also be utilized to perform radiomics, which has shown encouraging initial results in predicting BC grade and local stage. In this article, the current state of evidence supporting MRI in local, regional, and distant staging in patients with BC is reviewed. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:649-667.

Trimodality Therapy for Muscle-Invasive Bladder Cancer: Recent Advances and Unanswered Questions

PURPOSE OF REVIEW

Bladder-sparing trimodality therapy (TMT) has become an accepted alternative to cystectomy for selected muscle invasive bladder cancer (MIBC) patients unfit for cystectomy or opting for bladder preservation. This review will summarize recent advances in TMT for MIBC.

RECENT FINDINGS

A growing body of literature has emerged which supports the use of TMT. However, its delivery is yet to be standardized. The role of chemotherapy and predictive biomarkers remain to be elucidated. Novel bladder-sparing approaches, drug combinations including immunotherapy and targeted therapies are under investigation in clinical trials, with the goal of ultimately enhancing survival and quality of life outcomes. Recent advances in TMT have made bladder preservation possible for MIBC patients seeking an alternative local therapy to cystectomy. With careful patient selection, TMT offers comparable survival outcomes to cystectomy, and improved quality of life as patients are able to successfully retain their bladder.

Influence of preoperative hydronephrosis and ureteral orifice involvement in the survival of patients undergoing radical cystectomy: A retrospective comparative study

OBJECTIVE

The aim of the present study was to evaluate the influence of preoperative hydronephrosis and ureteral orifice involvement (UOI) on survival of patients undergoing radical cystectomy (RC) for bladder cancer (BC).

MATERIAL AND METHODS

A total of 162 patients with BC underwent RC between January 2006 and March 2017. Patients were divided into two groups for both presences of preoperative hydronephrosis and orifice involvement at final pathology. Additionally, tumors with orifice involvement were subgrouped histopathologically after RC as those with only UOI and those with invasive to the ureter with an additional concurrent site at final pathology.

RESULTS

Preoperative hydronephrosis was detected in 57 patients. Preoperative and postoperative creatinine on month 3 were higher in the preoperative hydronephrosis (+) group (p<0.001). In addition, postoperative T stage, surgical margin positivity, invasion of urethra, and pathological upstaging were higher in this group. Cancer-specific survival (CSS) and overall survival (OS) were better in the hydronephrosis (-) group than in the hydronephrosis (+) group (p=0.001 and p=0.001, respectively). Preoperative hydronephrosis was found to be an independent factor in pathological upstaging. Patients were divided into two groups according to the presence of UOI. Group 1 consisted of patients without UOI, and group 2 with UOI. Preoperative hydronephrosis, hydronephrosis grade, and T stage were statistically higher in tumors with UOI. Moreover, CSS and OS were lower in group 2 than in group 1.

CONCLUSION

Preoperative hydronephrosis and UOI are predicting factors on survival of patients undergoing RC for BC. Preoperative hydronephrosis was found to be an independent factor in pathological upstaging.

A systematic review and meta-analysis of the impact of lymphovascular invasion in bladder cancer transurethral resection specimens

The aim of the present review was to assess the prognostic impact of lymphovascular invasion (LVI) in transurethral resection (TUR) of bladder cancer (BCa) specimens on clinical outcomes. A systematic review and meta-analysis of the available literature from the past 10 years was performed using MEDLINE, EMBASE and Cochrane library in August 2017. The protocol for this systematic review was registered on PROSPERO (Central Registration Depository: CRD42018084876) and is available in full on the University of York website. Overall, 33 studies (including 6194 patients) evaluating the presence of LVI at TUR were retrieved. LVI was detected in 17.3% of TUR specimens. In 19 studies, including 2941 patients with ≤cT1 stage only, LVI was detected in 15% of specimens. In patients with ≤cT1 stage, LVI at TUR of the bladder tumour (TURBT) was a significant prognostic factor for disease recurrence (pooled hazard ratio [HR] 1.97, 95% CI: 1.47-2.62) and progression (pooled HR 2.95, 95% CI: 2.11-4.13), without heterogeneity (I² = 0.0%, P = 0.84 and I² = 0.0%, P = 0.93, respectively). For patients with cT1-2 disease, LVI was significantly associated with upstaging at time of radical cystectomy (pooled odds ratio 2.39, 95% CI: 1.45-3.96), with heterogeneity among studies (I² = 53.6%, P = 0.044). LVI at TURBT is a robust prognostic factor of disease recurrence and progression in non-muscle invasive BCa. Furthermore, LVI has a strong impact on upstaging in patients with organ-confined disease. The assessment of LVI should be standardized, reported, and considered for inclusion in the TNM classification system, helping clinicians in decision-making and patient counselling.

The dog as an animal model for bladder and urethral urothelial carcinoma: Comparative epidemiology and histology

Despite the recent approval of several novel agents for patients with metastatic urothelial carcinoma (UC), survival in this setting remains poor. As such, continued investigation into novel therapeutic options remains warranted. Pre-clinical development of novel treatments requires an animal model that accurately simulates the disease in humans. The aim of the present study was to evaluate the dog as an animal model for human UC. A total of 260 cases of spontaneous, untreated canine primary urethral and urinary bladder UC, were epidemiologically and histologically assessed and classified based on the current 2016 World Health Organization (WHO) tumor classification system. Canine data was compared with human data available from scientific literature. The mean age of dogs diagnosed with UC was 10.22 years (range, 4–15 years), which is equivalent to 60–70 human years. The results revealed a high association between UC diagnosis with the female sex [odds ratio (OR) 3.51; 95% confidence interval (CI) 2.57–4.79; P<0.001], surgical neutering (OR 4.57; 95% CI 1.87–11.12; P<0.001) and breed (OR 15.11 for Scottish terriers; 95% CI 8.99–25.41; P<0.001). Based on the 2016 WHO tumor (T), node and metastasis staging system, the primary tumors were characterized as T1 (38%), T2a (28%), T2b (13%) and T3 (22%). Non-papillary, flat subgross tumor growth was strongly associated with muscle invasion (OR 31.00; P<0.001). Irrespective of subgross growth pattern, all assessable tumors were invading beyond the basement membrane compatible with infiltrating UC. Conventional, not further classifiable infiltrating UC was the most common type of tumor (90%), followed by UC with divergent, squamous and/or glandular differentiation (6%). Seven out of the 260 (2.8%) cases were classified as non-urothelial based on their histological morphology. These cases included 5 (2%) squamous cell carcinomas, 1 (0.4%) adenocarcinoma and 1 (0.4%) neuroendocrine tumor. The 2 most striking common features of canine and human UC included high sex predilection and histological tumor appearance. The results support the suitability of the dog as an animal model for UC and confirm that dogs also spontaneously develop rare UC subtypes and bladder tumors, including plasmacytoid UC and neuroendocrine tumor, which are herein described for the first time in a non-experimental animal species.

Urothelial carcinoma involving the ureteral orifice: a clinicopathologic analysis of 93 cases

Although tumors involving the bladder and ureter have been well described, there are only few studies in the pathology literature specifically analyzing tumors involving the ureteral orifice (UO). A search was performed for biopsy and resection specimens (transurethral resection, radical cystectomy/cystoprostatectomy, nephroureterectomy and bladder cuff resection) of urothelial carcinoma (UCa) involving the UO. Ninety-three cases were identified. Sixty-two (67%) patients were male. Mean patient age was 71 years (range, 43-91 years). Forty-two of 93 (45%) cases were invasive UCa (41 high-grade UCa; 1 low-grade UCa); 17/42 (40%) were invasive into muscularis propria. Tumor laterality was as follows: right side, 43 (46% of cases); left side, 41 (44%); bilateral, 4 (4.5%); and in 5 cases (5.5%), the laterality was not specified by the urologist. Seven cases of UCa with variant histology were also identified. Five patients had lymph node (LN) metastasis at the time of resection, and another 3 presented with LN or distant metastasis after resection (range, 4-38 months). Although this study focused primarily on the index tumor involving the UO (Group 1 cases are those with only UO involvement), in 70/93 (75%) cases (Group 2 cases), at least one other tumor was located at another site within the bladder. The fact that the majority of cases (75%) had tumors located at other sites of the bladder, emphasizes that careful examination of the UO needs to be performed by both urologists and pathologists when examining cases of UCa of the bladder.

Challenges in Pathologic Staging of Bladder Cancer: Proposals for Fresh Approaches of Assessing Pathologic Stage in Light of Recent Studies and Observations Pertaining to Bladder Histoanatomic Variances

The paradigm of pathologic stage (pT) categorization in bladder cancer remains the depth of invasion into the different histologic layers of the bladder wall. However, the approaches to assigning pT stage category toward an enhanced outcome stratification have been marked by challenges and innovations, due in part to our growing appreciation of the surprisingly perplexing bladder histoanatomy. Upstaging of pT1 tumors after radical cystectomy is substantial and underscores the potential value of pT1 substaging in transurethral resection (TUR) specimens. The 2017 American Joint Committee on Cancer tumor-node-metastasis system recommends pT1 substaging but recognizes the need to optimize the approach. Over the years, the cut-off for microinvasion has been significantly lowered to 0.5 mm and is now a promising scheme for pT1 (micrometric) substaging. Unlike the micrometric approach, histoanatomic substaging using muscularis mucosae (MM) and vascular plexus as landmarks is less feasible in TUR specimens and inconsistent in stratifying the outcome of pT1 tumors. The lamina propria possesses inherent variations in depth, MM, and vascular plexus dispositions that should be factored in future pT1 substaging proposals. Histoanatomic variations among the bladder regions also occur, and studies suggest that trigone and bladder neck cancers may have more adverse outcomes. The muscularis propria (MP), besides being the essential histologic landmark for assigning pT2 stage category, is also considered a surrogate for the adequacy of TUR, furthering the importance of identifying its presence in TUR specimens. MP, however, may be mimicked by hyperplastic or isolated MP-like MM muscle bundles in the lamina propria with overstaging implications, and caution should be exercised in distinguishing these 2 muscle types morphologically and immunohistochemically. Presence of additional superficial MP unique from the detrusor muscle proper may also complicate staging at the trigone and ureter insertion sites. With regard to the depth of MP invasion, large and multicenter studies have reaffirmed the prognostic significance of pT2a/b subcategories. It is revealed that there are at least 3 ways used to demarcate the irregular MP to perivesical soft tissue junction, and use of a common criterion indicates improvement in pT2b/pT3a staging reproducibility. Although studies have shown significantly poorer outcome in pT3b compared with pT3a tumors, this designation has a substantial reliance on the prosector's gross assessment of perivesical soft tissue invasion which if performed incorrectly may lead to staging inaccuracy of pT3 tumors. The 8th edition of the American Joint Committee on Cancer has updated the staging schema for bladder cancers with concomitant prostatic stromal invasion and cancers within bladder diverticula. Because of 2 possible pT designations, prostatic stromal invasion in TUR specimens should not be automatically staged as either pT4a or pT2 (urethral). Recent data support that bladder cancer invading into the seminal vesicle has comparable outcome to pT4b tumors. Interestingly, several studies in pT4a tumors, which are staged based on sex-specific organs, have shown poorer outcome in females than males after radical cystectomy, and while there are possibly several reasons, they may also include anatomic factors. Despite the progress has been made, work remains to be done to inform future bladder cancer pT category definitions and their reproducibility in application and prognostication.

Pelvic Lymph Node Dissection may be Limited on the Contralateral Side in Strictly Unilateral Bladder Cancer without Compromising Oncological Radicality

BACKGROUND

Results of a dynamic multimodality mapping study showed no lymphatic drainage of the lateral bladder wall to the contralateral internal iliac region.

OBJECTIVES

To validate whether pathoanatomical mapping in bladder cancer (BC) patients can confirm these results.

METHODS

Between 01/2000 and 07/2013, 825 BC patients preoperatively staged ≥pT1 and without clinical signs of metastases (cN0 cM0) underwent extended pelvic lymph node dissection (ePLND) and radical cystectomy at our department. Of these patients, 23% (193/825) were lymph node (LN) positive in the pathological specimen; 26% (51/193) of this subgroup had strictly unilateral BC. Pathoanatomical mapping was used to retrospectively validate the distribution of LN involvement in these 51 patients.

RESULTS

A median of 35 LNs were removed per patient (range: 13-80 LNs), with a median of 2 positive LNs (range: 1-14 LNs). 27% (14/51) of patients presented with LN metastases on the contralateral side. No positive LNs were found in the contralateral internal iliac region or the contralateral fossa of Marcille. 10% (5/51) of patients had LN metastases only on the contralateral side without evidence of metastases on the tumor-bearing side.

CONCLUSIONS

Our findings corroborate the data of a dynamic mapping study showing bilateral lymphatic drainage in almost one third of patients with strictly unilateral BC, but no lymphatic drainage from the lateral bladder wall to the contralateral internal iliac region. If prospective studies confirm these results, the contralateral internal iliac region may be omitted during ePLND in patients with strictly unilateral BC.