Prognostic factors in T1 bladder urothelial carcinoma: the value of recording millimetric depth of invasion, diameter of invasive carcinoma, and muscularis mucosa invasion

Prognostic value of micrometric substaging in pT1 bladder cancer patients treated with en-bloc transurethral resection

AIMS

We aimed to assess the oncological impact of micrometric extent of invasion in patients with pT1 bladder cancer (BCa) who underwent en-bloc resection for bladder tumour (ERBT).

METHODS AND RESULTS

We retrospectively analysed the records and specimens of 106 pT1 high-grade BCa patients who underwent ERBT. The extent of invasion, such as depth from basal membrane, number of invasive foci, maximum width of invasive focus, muscularis mucosae invasion and infiltration pattern (pattern A: solid sheet-like, nodular or nested growth, pattern B: trabecular, small cluster or single-cell pattern) were evaluated by a single genitourinary pathologist. The end-points were recurrence-free (RFS) and progression-free survival (PFS). Within a median follow-up of 23 months, overall, 36 patients experienced recurrence and 13 patients experienced disease progression. The 2-year PFS differed significantly depending on depth from basal membrane (< 1.3 mm: 94.8% versus ≧ 1.3 mm: 65.2%, P = 0.005), maximum width of invasive focus (< 4 mm: 91.7% versus ≧ 4 mm: 62.3%, P < 0.001), muscularis mucosae (MM) invasion (above MM = 96.1% versus into or beyond MM = 64.8%, P = 0.002) and infiltration pattern (pattern A: 100% versus pattern B: 83.3%, P = 0.037). In a multivariable analysis, MM invasion [hazard ratio (HR) = 4.54, 95% confidence interval (CI) = 1.25-16.5] and maximum width of invasive focus ≧ 4 mm (HR = 4.79, 95% CI = 1.25-16.5) were independent prognostic factors of progression.

CONCLUSIONS

En-bloc resection facilitates the evaluation of pathologic variables that might be useful in predicting disease recurrence and progression. In particular, not only the MM invasion but also the maximum width of invasion focus, reflecting the invasive volume, appear to be reliable prognosticators for disease progression.

Detecting Muscle Invasion of Bladder Cancer: An Application of Diffusion Kurtosis Imaging Ratio and Vesical Imaging-Reporting and Data System

BACKGROUND

Independent factors are needed to supplement vesical imaging-reporting and data system (VI-RADS) to improve its ability to identify muscle invasive bladder cancer (MIBC).

PURPOSE

To assess the correlation between MIBC and diffusion kurtosis imaging (DKI) ratio, VI-RADS, and other factors (such as tumor location).

STUDY TYPE

Retrospective.

POPULATION

Sixty-eight patients (50 males and 18 females; age: 70.1 ± 9.5 years) with bladder urothelial carcinoma.

FIELD STRENGTH/SEQUENCE

1.5 T, conventional diffusion-weighted imaging (DWI), and DKI (single shot echo-planar sequence).

ASSESSMENT

Three radiologists independently measured the diffusion parameters of each bladder cancer (BCa) and obturator internus, including the mean apparent diffusion coefficient (ADCmean), mean kurtosis (MK), and mean diffusion (MD). And the ratio of diffusion parameters between BCa and obturator internus was calculated (diffusion parameter ratio = bladder cancer:obturator internus). Based on the VI-RADS, the target lesions were independently scored. Furthermore, the actual tumor-wall contact length (ACTCL) and absolute tumor-wall contact length (ABTCL) were measured.

STATISTICAL TESTS

Multicollinearity among independent variables was evaluated using the variance inflation factor (VIF). Multivariable logistic regression analysis was used to determine the independent risk factors of MIBC. The receiver operating characteristic curve was used to evaluate the efficacy of each variable in detecting MIBC. The DeLong test was used to compare the area under the curve (AUC). A P < 0.05 was considered statistically significant.

RESULTS

MKratio (median: 0.62) and VI-RADS were independent risk factors for MIBC. AUCs for MKratio, VI-RADS, and MKratio combined with VI-RADS in assessing MIBC were 0.895, 0.871, and 0.973, respectively. MKratio combined with VI-RADS was more effective in diagnosing MIBC than VI-RADS alone.

DATA CONCLUSIONS

MKratio has potential to assist the assessment of MIBC. MKratio can be used as a supplement to VI-RADS for detecting MIBC.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 2.

The Impact of Second Opinion Expert Pathology Review in Patient Management at the Time of Transurethral Resection of the Bladder

BACKGROUND AND OBJECTIVE

Pathological features in non-muscle-invasive bladder cancer specimens are pivotal in determining correct patients' therapeutic management. Sparse data exist regarding the importance of second opinion performed by an expert uropathologist. This study aimed to assess the importance of a second opinion by an expert uropathologist in the management of bladder cancer.

METHODS

The study relied on 272 bladder cancer specimens from 231 patients seeking a pathology second opinion after transurethral resection of the bladder for a clinical suspicion of bladder cancer, relapse, or second-look procedure. Pathology second opinion was offered by an experienced fellowship-trained uropathologist. Discrepancies were recorded considering primary tumor staging, the presence of muscularis propria, and the presence of histological variants. Cases were categorized as no significant discordance, major discordance without management change, and major discordance with management change according to the European Urology Association (EAU) guidelines.

KEY FINDINGS AND LIMITATIONS

Among 272 second opinion cases, 39% (108/272) had major discordance and 28% (75/272) had major discordance with change in management according to the EAU guidelines. Upstaging and downstaging were reported in 66 (24%) patients. Improper identification of the presence of muscularis propria was found in 46 (17%) cases, of which 11 (4%) were deemed clinically relevant. Differences regarding the presence of histological variants were diagnosed in 40 cases (15%), resulting in eight (3%) changes in clinical management. In ten specimens (4%), multiple clinically relevant discrepancies were found.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The second opinion evaluation changed the clinical management in 25% of the cases. These results support the importance of specimen review by an expert uropathologist as a major driver in the correct bladder cancer management.

PATIENT SUMMARY

We investigated the importance of a second opinion performed by an expert uropathologist in the management of bladder cancer. We found that 25% had their treatment plan changed due to the revised pathological report.

International Society of Urological Pathology (ISUP) Consensus Conference on Current Issues in Bladder Cancer: Working Group 3: Subcategorization of T1 Bladder Cancer

Emerging data on T1 bladder cancer subcategorization (aka substaging) suggests a correlation with oncological outcomes. The International Society of Urological Pathology (ISUP) organized the 2022 consensus conference in Basel, Switzerland to focus on current issues in bladder cancer and tasked working group 3 to make recommendations for T1 subcategorization in transurethral bladder resections. For this purpose, the ISUP developed and circulated a survey to their membership querying approaches to T1 bladder cancer subcategorization. In particular, clinical relevance, pathological reporting, and endorsement of T1 subcategorization in the daily practice of pathology were surveyed. Of the respondents of the premeeting survey, about 40% do not routinely report T1 subcategory. We reviewed literature on bladder T1 subcategorization, and screened selected articles for clinical performance and practicality of T1 subcategorization methods. Published literature offered evidence of the clinical rationale for T1 subcategorization and at the conference consensus (83% of conference attendants) was obtained to report routinely T1 subcategorization of transurethral resections. Semiquantitative T1 subcategorization was favored (37%) over histoanatomic methods (4%). This is in line with literature findings on practicality and prognostic impact, that is, a shift of publications from histoanatomic to semiquantitative methods or by reports incorporating both methodologies is apparent over the last decade. However, 59% of participants had no preference for either methodology. They would add a comment in the report briefly stating applied method, interpretation criteria (including cutoff), and potential limitations. When queried on the terminology of T1 subcategorization, 34% and 20% of participants were in favor of T1 (microinvasive) versus T1 (extensive) or T1 (focal) versus T1 (nonfocal), respectively.

Recent Advances in the Classification of Bladder Cancer - Updates from the 5th Edition of the World Health Organization Classification of the Urinary and Male Genital Tumors

BACKGROUND

The World Health Organization Classification (WHO) of Urinary and Male Genital Tumors has recently been updated to its 5th edition. The new edition presents a comprehensive approach to the classification of urinary and male genital tumors with an incorporation of morphologic, clinical, and genomic data.

OBJECTIVE

This review aims to update the new classification of bladder cancer in the 5th edition and to highlight important changes in nomenclatures, diagnostic criteria, and molecular characterization, as compared to the 4th edition.

METHODS

The pathologic classification of bladder cancer in the 5th edition of WHO Classification of Urinary and Male Genital Tumours was compared to that in the 4th edition. PubMed was searched using key words, including bladder cancer, WHO 1973, WHO 1998, WHO 2004, WHO 2016, histology, pathology, genomics, and molecular classification in the time frame from 1973 to August of 2022. Other relevant papers were also consulted, resulting in the selection of 81 papers as references.

RESULTS

The binary grading of papillary urothelial carcinoma (UC) is practical, but it may be oversimplified and contribute to "grade migration" in recent years. An arbitrary cutoff (5%) has been proposed for bladder cancers with mixed grades. The diagnosis of papillary urothelial neoplasm with low malignant potential has been dramatically reduced in recent years because of overlapping morphology and treatment with low-grade papillary UC. An inverted growth pattern should be distinguished from true (or destructive) stromal invasion in papillary UC. Several methods have been proposed for pT1 tumor substaging, but it is often challenging to substage pT1 tumors in small biopsy specimens. Bladder UC shows a high tendency for divergent differentiation, leading to several distinct histologic subtypes associated with an aggressive clinical behavior. Molecular classification based on the genomic analysis may be a useful tool in the stratification of patients for optimal treatment.

CONCLUSIONS

The 5th edition of WHO Classification of Urinary and Male Genital Tumours has made several significant changes in the classification of bladder cancer. It is important to be aware of these changes and to incorporate them into routine clinical practice.

Prospective Validation of the ROL System in Substaging pT1 High-Grade Urothelial Carcinoma: Results from a Mono-Institutional Confirmatory Analysis in BCG Treated Patients

Patients with pT1 high-grade (HG) urothelial carcinoma (UC) and a very high risk of progression might benefit from immediate radical cystectomy (RC), but this option remains controversial. Validation of a standardized method to evaluate the extent of lamina propria (LP) invasion (with recognized prognostic value) in transurethral resection (TURBT) specimens is still needed. The Rete Oncologica Lombarda (ROL) system showed a high predictive value for progression after TURBT in recent retrospective studies. The ROL system was supposed to be validated on a large prospective series of primary urothelial carcinomas from a single institution. From 2016 to 2020, we adopted ROL for all patients with pT1 HG UC on TURBT. We employed a 1.0-mm threshold to stratify tumors in ROL1 and ROL2. A total of 222 pT1 HG UC were analyzed. The median age was 74 years, with a predominance of men (73.8%). ROL was feasible in all cases: 91 cases were ROL1 (41%), and 131 were ROL2 (59%). At a median follow-up of 26.9 months (IQR 13.8-40.6), we registered 81 recurrences and 40 progressions. ROL was a significant predictor of tumor progression in both univariable (HR 3.53; CI 95% 1.56-7.99; p < 0.01) and multivariable (HR 2.88; CI 95% 1.24-6.66; p = 0.01) Cox regression analyses. At Kaplan-Meier estimates, ROL showed a correlation with both PFS (p = 0.0012) and RFS (p = 0.0167). Our results confirmed the strong predictive value of ROL for progression in a large prospective series. We encourage the application of ROL for reporting the extent of LP invasion, substaging T1 HG UC, and improving risk tables for urological decision-making.

Combination of Two T1 Substaging Systems (T1a/b/c and T1m/e) Better Predicts Tumor Outcomes in Patients with T1 High Grade Bladder Cancer

BACKGROUND

T1 substaging is a predictive factor for non-muscle-invasive bladder cancer, and two types of T1 substaging systems (T1a/b/c and T1m/e) are currently in use. However, the predictive ability of both systems is poor, and there is debate over which system is better.

OBJECTIVE

To confirm whether combination of two T1 substaging systems can improve the predictive ability of T1 substaging for tumor outcomes.

METHODS

Patients with primary pT1 high-grade bladder cancer from three centers were included. All tumors were assessed with T1a/b/c and T1m/e substaging. A new variable named COMB was developed in which patients were stratified into T1a/b&T1m, T1a/b&T1e, T1c&T1m or T1c&T1e subgroups. A time-dependent receiver operating characteristic curve (ROC) analysis was used to test whether the accuracy of prediction could be improved with COMB.

RESULTS

A total of 239 patients with primary pT1HG were analyzed. No tumor was T1c&T1m, and therefore, only three types of combinations were evaluated: T1a/b&T1m (62 patients), T1a/b&T1e (124 patients) and T1c&T1e (53 patients). Regardless of all patients or those treated with Re-TURBt and adequate BCG, patients with T1a/b&T1m have the best prognosis, and those with T1c&T1e have the poorest prognosis. The time-dependent ROC showed that, for both recurrence and progression, COMB had a higher AUC than T1a/b/c and T1m/e, regardless of population.

CONCLUSIONS

Compared with either system alone, the combination of two T1 substaging systems improves the predictive ability of T1 substaging for tumor outcomes.

Urothelial Carcinoma: Update on Staging and Reporting, and Pathologic Changes Following Neoadjuvant Chemotherapies

Staging and reporting of cancers of the urinary tract have undergone major changes in the past decade to meet the needs for improved patient management. Substantial progress has been made. There, however, remain issues that require further clarity, including the substaging of pT1 tumors, grading and reporting of tumors with grade heterogeneity, and following NAC. Multi-institutional collaborative studies with prospective data will further inform the accurate diagnosis, staging, and reporting of these tumors, and in conjunction with genomic data will ultimately contribute to precision and personalized patient management.

The Role of WRAP53 in Cell Homeostasis and Carcinogenesis Onset

The WD repeat containing antisense to TP53 (WRAP53) gene codifies an antisense transcript for tumor protein p53 (TP53), stabilization (WRAP53α), and a functional protein (WRAP53β, WDR79, or TCAB1). The WRAP53β protein functions as a scaffolding protein that is important for telomerase localization, telomere assembly, Cajal body integrity, and DNA double-strand break repair. WRAP53β is one of many proteins known for containing WD40 domains, which are responsible for mediating a variety of cell interactions. Currently, WRAP53 overexpression is considered a biomarker for a diverse subset of cancer types, and in this study, we describe what is known about WRAP53β's multiple interactions in cell protein trafficking, Cajal body formation, and DNA double-strand break repair and its current perspectives as a biomarker for cancer.

Nonmuscle-invasive bladder cancer, old problems, new insights

PURPOSE OF REVIEW

Nonmuscle-invasive bladder cancer (NMIBC) is the most frequent bladder cancer and represents around 75% of bladder cancers. This review will discuss known challenges and recent advances in staging, grading and treatment stratification based on pathology.

RECENT FINDINGS

Pathological staging and grading in NMIBC remains challenging and different techniques exist. Substaging has been shown to be of prognostic relevance and to help predict treatment response in patients receiving Bacillus Calmette-Guérin (BCG) therapy, which is the treatment of choice for high-grade NMIBC. Recent advances in molecular classification and artificial intelligence were also able to show promising results in the stratification of patients.

SUMMARY

Many challenges in the diagnosis of NMIBC are still unresolved and ask for more prospective research. New technologies, molecular insights and AI will help in the upcoming years to better stratify and manage these patients.

Subcategorization of T1 Bladder Cancer on Biopsy and Transurethral Resection Specimens for Predicting Progression

CONTEXT.—

Despite continued surveillance and intravesical therapy, a significant subset of patients with lamina propria-invasive bladder cancer (T1) will progress to muscle-invasive disease or metastases.

OBJECTIVE.—

To analyze the value of pathologic subcategorization of T1 disease in predicting progression.

DESIGN.—

Six substaging methods were applied to a retrospective cohort of 73 patients, with pT1 urothelial carcinoma diagnosed on biopsy/transurethral resection. Additionally, the immunohistochemistry for GATA3 and cytokeratin 5/6 (CK5/6) was performed to study the prognostic value of stratifying T1 cancers into luminal or basal phenotypes.

RESULTS.—

On follow-up (mean, 46 months), 21 (29%) experienced at least 1 recurrence without progression, and 16 (22%) had progression to muscle-invasive disease and/or distant metastasis. No differences were noted between progressors and nonprogressors with regard to sex, age, treatment status, medical history, tumor grade, and presence of carcinoma in situ. Substaging using depth of invasion (cutoff ≥1.4 mm), largest invasive focus (≥3.6 mm), aggregate linear length of invasion (≥8.9 mm), and number of invasive foci (≥3 foci) correlated significantly with progression and reduced progression-free survival, whereas invasion into muscularis mucosa or vascular plexus, or focal versus extensive invasion (focal when ≤2 foci, each <1 mm) failed. Patients with luminal tumors had higher incidence of progression than those with nonluminal tumors (27% versus 11%), although the difference was statistically insignificant (P = .14).

CONCLUSIONS.—

Substaging of T1 bladder cancers should be attempted in pathology reports. Quantifying the number of invasive foci (≥3) and/or measuring the largest contiguous focus of invasive carcinoma (≥3.6 mm) are practical tools for prognostic substaging of T1 cancers.

Bladder Cancer Sample Handling and Reporting: Pathologist's Point of View

The aim of this narrative review is to provide adequate information on handling and reporting of the bladder cancer samples to improve the closely collaboration between pathologists and urologists. The main (but not exclusive) research tool used was PubMed and 87 references were selected and quoted in the text. We have considered handling of biopsies, transurethral resection (TUR), and cystectomy specimens to summarize the different methods of sampling and the related issues. Moreover, we considered and discussed the main prognostic factors, such as histological tumor type, grade, and stage of bladder cancer, that should be described in the pathological report. In addition, critical issues encountered in the interpretation of histological samples were discussed.

T1 Bladder Cancer: Comparison of the Prognostic Impact of Two Substaging Systems on Disease Recurrence and Progression and Suggestion of a Novel Nomogram

Background: The T1 substaging of bladder cancer (BCa) potentially impacts disease progression. The objective of the study was to compare the prognostic accuracy of two substaging systems on the recurrence and progression of primary pathologic T1 (pT1) BCa and to test a nomogram based on pT1 substaging for predicting recurrence-free survival (RFS) and progression-free survival (PFS). Methods: The medical records of 204 patients affected by pT1 BCa were retrospectively reviewed. Substaging was defined according to the depth of lamina propria invasion in T1_a-c and the extension of the lamina propria invasion to T1-microinvasive (T1_m) or T1-extensive (T1_e). Uni- and multivariable Cox regression models evaluated the independent variables correlated with recurrence and progression. The predictive accuracies of the two substaging systems were compared by Harrell's C index. Multivariate Cox regression models for the RFS and PFS were also depicted by a nomogram. Results: The 5-year RFS was 47.5% with a significant difference between T1_c and T1_a (p = 0.02) and between T1_e and T1_m (p < 0.001). The 5-year PFS was 75.9% with a significant difference between T1_c and T1_a (p = 0.011) and between T1_e and T1_m (p < 0.001). Model T1_m-e showed a higher predictive power than T1_a-c for predicting RFS and PFS. In the univariate and multivariate model subcategory T1e, the diameter, location, and number of tumors were confirmed as factors influencing recurrence and progression after adjusting for the other variables. The nomogram incorporating the T1_m-e model showed a satisfactory agreement between model predictions at 5 years and actual observations. Conclusions: Substaging is significantly associated with RFS and PFS for patients affected by T1 BCa and should be included in innovative prognostic nomograms.

The Genitourinary Pathology Society Update on Classification of Variant Histologies, T1 Substaging, Molecular Taxonomy, and Immunotherapy and PD-L1 Testing Implications of Urothelial Cancers

The Genitourinary Pathology Society (GUPS) undertook a critical review of the recent advances in bladder cancer focusing on important topics of high interest for the practicing surgical pathologist and urologist. This review represents the second of 2 manuscripts ensuing from this effort. Herein, we address the effective reporting of bladder cancer, focusing particularly on newly published data since the last 2016 World Health Organization (WHO) classification. In addition, this review focuses on the importance of reporting bladder cancer with divergent differentiation and variant (subtypes of urothelial carcinoma) histologies and the potential impact on patient care. We provide new recommendations for reporting pT1 staging in diagnostic pathology. Furthermore, we explore molecular evolution and classification, emphasizing aspects that impact the understanding of important concepts relevant to reporting and management of patients.

Substaging of pT1 Urothelial Bladder Carcinoma Predicts Tumor Progression and Overall Survival

INTRODUCTION

Limitations in tumor staging and the heterogeneous natural evolution of pT1 urothelial bladder carcinoma (UBC) make the choice of treatment challenging. We evaluated if histopathological substaging (pT1a, pT1b, and pT1c) helps predict disease recurrence, progression, and overall survival following transurethral resection of the bladder (TURB).

METHODS

We included 239 consecutive patients diagnosed with pT1 UBC at TURB in a single institution since 2001. Each sample was interpreted by our specialized uropathologists trained to subclassify pT1 stage. Three groups were distinguished according to the degree of invasion: T1a (up to the muscularis mucosae [MM]), T1b (into the MM), and T1c (beyond the MM).

RESULTS

T1 substaging was possible in 217/239 (90%) patients. pT1a, b, and c occurred in 124 (57), 59 (27), and 34 (16%), respectively. The median follow-up was 3.1 years, with a cumulative recurrence rate of 52%, progression rate of 20%, and survival rate of 54%. Recurrence was not significantly associated with tumor substage (p = 0.61). However, the Kaplan-Meier survival analysis showed a significantly higher progression rate among T1b (31) and T1c (26%) tumors than T1a (13%) (log-rank test: p = 0.001) stages. In a multivariable model including gender, age, ASA score, smoking, tumor grade, and presence of carcinoma in situ, T1 substage was the single variable significantly associated with progression-free survival (HR 1.7, p = 0.005). Nineteen patients (9%) needed radical cystectomy; among them, 12/19 (63%) had an invasive tumor. Overall survival was significantly associated with tumor substaging (p = 0.001).

CONCLUSION

Histopathological substaging of pT1 UBC is significantly associated with tumor progression and overall survival and therefore appears to be a useful prognostic tool to counsel patients about treatment options.

Bicentric Retrospective Analysis of en Bloc Resection and Muscularis Mucosae Detection Rate in Non-Muscle Invasive Bladder Tumors: A Real-World Scenario

Introduction

For risk stratification of non-muscle invasive bladder cancer (NMIBC), the depth of stromal invasion can be further classified, where the lamina muscularis mucosae (MM) serves as a reference structure. While the overall identifiability of MM in standard transurethral specimens is low, en bloc resection may help in identification and overall orientation. The aims of this study were to report the detection rate of MM in en bloc resected bladder tumors (ERBT) and to provide real-world information on tissue stability and preservation of en bloc architecture during recovery and processing for histopathologic evaluation.

Methods

Thirty-four ERBT specimens were histologically re-evaluated with regard to MM detectability and structure as well as the presence of en bloc architecture and further histologic features. Associations with tumor size and energy source and within histologic parameters were assessed by standard Pearson's chi-squared analyses and Cramér’s V effect size testing (V).

Results

The first parameter assessed was MM detection rate. In 19 out of 34 samples (56%) MM was detectable: scattered in 9 cases (26%), interrupted in 8 cases (24%) and continuous in 2 cases (6%). The second parameter assessed was preservation of en bloc architecture. In 11 out of 34 samples (32%), en bloc architecture could not be confirmed, and these samples served as a reference group for the detection of MM. Preservation of en bloc architecture was associated with an increased MM detection rate (MM in en bloc preserved 16/23, 70% vs. non-preserved 3/11, 27%; p = 0.020; V = 0.398) and with tumor size (p = 0.005; V = 0.595). Medium-sized tumors (1.1–2 cm) were best preserved. The choice of energy source did not show relevant association with en bloc architecture (p = n.s.).

Conclusions

In line with recent publications, ERBT increases the MM detection rate considerably. However, a third of the ERBT specimens lost en bloc architecture during sample recovery and processing. Tumor size is a relevant factor, with optimal architecture preservation between 1 and 2 cm. Optimizing resection techniques, recovery, transport, and diagnostic processing of ERBT samples is warranted to verify the diagnostic value of MM-based substaging.

Stage T1 bladder cancer: diagnostic criteria and pitfalls

Accurate pathological staging is crucial for patient management. Patients with T1 bladder cancer are at risk of recurrence, progression, and death of cancer. Recognition of early invasion (stage T1 disease) in urothelial carcinoma remains one of the most challenging areas in urological surgical pathology practice. A logical roadmap to T1 diagnosis would include careful evaluation of histological grade, stromal epithelial interface, characteristics of the invading epithelium, and the stroma associated responses. Tangential sectioning, crush and cautery artifacts, and associated inflammatory infiltrate are commonly encountered problems and the source of pitfalls. In this review, we outline diagnostic criteria, common pitfalls, and different histological patterns of invasion into the lamina propria. Current recommendations on reporting of biopsy and transurethral resection specimens, molecular biomarkers, clinical implications of T1 cancer diagnosis and recent developments on the T1 substaging are also discussed. Most T1 bladder cancer patients will benefit from conservative management after restaging transurethral resection of bladder and bacillus Calmette-Guérin maintenance. Patients with high risk features, such as concurrent urothelial carcinoma in situ, increased depth of invasion, lymphovascular invasion, and variant histology among others, should be considered for early cystectomy.

Updates in Staging and Reporting of Genitourinary Malignancies

CONTEXT.—

The 8th edition of the American Joint Committee on Cancer (AJCC) staging manual changed the tumor, node, metastasis (TNM) classification systems of genitourinary malignancies in 2017. However, some of the changes appear not well appreciated or recognized by practicing pathologists.

OBJECTIVE.—

To review the major changes compared with the 7th edition in cancers of the prostate, penis, testis, bladder, urethra, renal pelvis/ureter, and kidney and discuss the challenges that pathologists may encounter.

DATA SOURCES.—

Peer-reviewed publications and the 8th and 7th editions of the AJCC Cancer Staging Manual.

CONCLUSIONS.—

This article summarizes the updated staging of genitourinary malignancies, specifically highlighting changes from the 7th edition that are relevant to the pathologic staging system. Pathologists should be aware of the updates made in hopes of providing clarification and the remaining diagnostic challenges associated with these changes.

Sub-Staging-Specific Differences in Recurrence-Free, Progression-Free, and Cancer-Specific Survival for Patients with T1 Bladder Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

The efficiency of the T1 sub-staging system on categorizing bladder cancer (BC) patients into subgroups with different clinical outcomes was unclear. We summarized relevant evidences, including recurrence-free survival (RFS), progression-free survival (PFS), and cancer-specific survival (CSS), to analyze the prognostic significance of T1 sub-stage.

METHODS

Systematic literature searches of MEDLINE, EMBASE, and the Cochrane Library were performed. We pooled data on recurrence, progression, and CSS from 35 studies.

RESULTS

The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) indicated the difference in RFS between T1a sub-stage and T1b sub-stage (HR 1.28, 95% CI 1.14-1.43, p < 0.001). The significant difference was observed in PFS between the 2 arms (HR 2.18, 95% CI 1.95-2.44, p < 0.001). Worse CSS was found in T1b patients than in T1a patients (HR 1.36, 95% CI 1.21-1.54, p < 0.001).

CONCLUSIONS

T1 sub-staging system based on the invasion depth into muscularis mucosae can be a significant prognostic factor for RFS, PFS, and CSS of patients with T1 BC. Urologists and pathologists are encouraged to work together to give a precise sub-stage classification of T1 BC, and T1 sub-staging system should be a routine part of any histopathological report when possible. Different treatment strategies need to be developed for both T1a BC and T1b BC.

pT1 high-grade bladder cancer: histologic criteria, pitfalls in the assessment of invasion, and substaging

Most patients with bladder carcinoma are diagnosed with non-muscle-invasive disease, stage Ta, and pT1. Stage remains as the single most important prognostic indicator in urothelial carcinoma. Among the pT1 bladder cancer patients, recurrence and progression of disease occur in 50% and 10%, respectively. The identification of high-risk patients within the pT1 subgroup remains an important clinical goal and an active field of research. Substaging of pT1 disease has been claimed as important histologic discriminator by the 2016 World Health Organization (WHO) classification of the genitourinary tract tumors and by the 8th edition of the American Joint Committee on Cancer (AJCC) staging manual supporting its implementation in clinical practice. Interobserver variation in pT1 diagnosis and the associated pitfalls in pT1 assessment are the critical pathological issues. The aim of this review paper is to provide the practicing pathologist with the state of the art of morphological and immunohistochemical features useful for the diagnosis of early invasive bladder carcinomas, including practical clues on how to avoid relevant interpretative pitfalls, and to summarize the current status of pT1 substaging.

Dataset for the reporting of urinary tract carcinoma-biopsy and transurethral resection specimen: recommendations from the International Collaboration on Cancer Reporting (ICCR)

The International Collaboration on Cancer Reporting (ICCR) is an alliance of major pathology organisations in Australasia, Canada, Europe, United Kingdom, and United States of America that develops internationally standardised, evidence-based datasets for the pathology reporting of cancer specimens. This dataset was developed by a multidisciplinary panel of international experts based on previously published ICCR guidelines for the production of cancer datasets. It is composed of Required (core) and Recommended (noncore) elements identified on the basis of literature review and expert consensus. The document also includes an explanatory commentary explaining the rationale behind the categorization of individual data items and provides guidance on how these should be collected and reported. The dataset includes nine required and six recommended elements for the reporting of cancers of the urinary tract in biopsy and transurethral resection (TUR) specimens. The required elements include specimen site, operative procedure, histological tumor type, subtype/variant of urothelial carcinoma, tumor grade, extent of invasion, status of muscularis propria, noninvasive carcinoma, and lymphovascular invasion (LVI). The recommended elements include clinical information, block identification key, extent of T1 disease, associated epithelial lesions, coexistent pathology, and ancillary studies. The dataset provides a structured template for globally harmonized collection of pathology data required for management of patients diagnosed with cancer of the urinary tract in biopsy and TUR specimens. It is expected that this will facilitate international collaboration, reduce duplication of effort in updating current national/institutional datasets, and be particularly useful for countries that have not developed their own datasets.

Comparative Application of Different Substaging Techniques for Non-Muscle Invasive Urothelial Carcinoma

To evaluate the diagnostic performance and clinical significance of 4 systems of substaging cases with non-muscle invasive urothelial bladder carcinoma. In addition 4 cutoff measures were evaluated for prediction of muscularis-mucosa invasion. Four substaging systems were applied to 57 NMIBC cases to assess which of these reported methods correlates best with recurrence and progression. On univariate regression analysis patients having tumor size more than 3 cm, solid tumor architecture, high grade, substage B, substage T1e, substage ROL 2 and Tumor depth more than 1 mm were associated with higher recurrence. On multivariate analysis all the four substaging systems, tumor size, grade and tumor type had significant prognostic value for recurrence. Regarding progression only the metric substaging method was associated with tumor progression (p = 0.04). However, on univariate and multivariate regression analysis none of the substaging systems showed prognostic significance and only solid tumor architecture and CIS had significant prognostic value for tumor progression. The ROC curve analysis showed that 1 mm depth of invasion had the best accuracy for detection of muscularis-mucosa invasion (80.2%). Using 1 mm cutoff in measuring the depth and 0.5 mm for the diameter of infiltration may provide clinically relevant information to guide a more personalized therapy for NMIBC. Inclusion of both measures in addition to other histopathologic variables may aid in the development of a scoring system.

Prognostic value of T1 substaging on oncological outcomes in patients with non-muscle-invasive bladder urothelial carcinoma: a systematic literature review and meta-analysis

Purpose

To evaluate the prognostic value of substaging on oncological outcomes in patients with T (or pT1) urothelial carcinoma of the bladder.

Methods

A literature search using PubMed, Scopus, Web of Science, and Cochrane Library was conducted on March 2019 to identify relevant studies according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. The pooled disease recurrence (DR) and disease progression (DP) rate in T1(or pT1) patients were calculated using a fixed or random effects model.

Results

Overall 36 studies published between 1994 and 2018 including a total of 6781 bladder cancer patients with T1(or pT1) stage were selected for the systematic review and meta-analysis. Twenty-nine studies reported significant association between tumor infiltration depth or muscularis mucosa (MM) invasion and oncological outcomes. Totally 12 studies were included in the meta-analysis. MM invasion (T1a/b/c [or pT1a/b/c] or T1a/b [or pT1a/b] substaging system) was associated with DR (pooled HR: 1.23, 95%CI: 1.01–1.49) and DP (pooled HR: 2.61, 95%CI: 1.61–4.23). Tumor infiltration depth (T1 m/e [or pT1 m/e] substaging system) was also associated with DR (pooled HR: 1.49, 95%CI: 1.11–2.00) and DP (pooled HR: 3.29, 95%CI: 2.39–4.51).

Conclusions

T1(or pT1) substaging in patients with bladder cancer is of prognostic value as it is associated with oncologic outcomes. Inclusion of this factors into the clinical decision-making process of this heterogeneous tumor may improve outcomes, while avoiding over- and under-treatment for T1(or pT1) bladder cancer.

The Role and Importance of Timely Radical Cystectomy for High-Risk Non-muscle-Invasive Bladder Cancer

Non-muscle-invasive bladder cancer accounts for the majority of incident bladder cancers but is a heterogeneous disease with variation in clinical presentation, course, and outcomes. Risk stratification techniques have attempted to identify those at highest risk of cancer recurrence and progression to help personalize and individualize treatment options. Radical cystectomy during the optimal window of curability could improve cancer outcomes; however, identifying the disease and patient characteristics as well as the correct timing to intervene remains difficult. We review the natural history of non-muscle-invasive bladder cancer, discuss different risk-stratification techniques and how they can help identify those most likely to benefit from radical treatment, and examine the evidence supporting the benefit of timely cystectomy.

Staging of bladder cancer

Urothelial carcinoma of the urinary bladder is a heterogeneous disease with multiple possible treatment modalities and a wide spectrum of clinical outcome. Treatment decisions and prognostic expectations hinge on accurate and precise staging, and the recently published American Joint Committee on Cancer (AJCC) Staging Manual, 8th edition, should be the basis for staging of urinary bladder tumours. It is unfortunate that the International Union Against Cancer (UICC) 8th edition failed to incorporate new data which is considered in the AJCC 8th edition. Thus, the AJCC 8th edition is the focus of this review. Several critical changes and clarifications are made by the AJCC 8th edition relative to the 7th edition. Although the most obvious changes in the 8th edition are in the N (i.e. perivesical lymph node involvement now classified as N1) and M (i.e. M1 is subdivided into M1a and M1b) categories, several points are clarified in the T category (e.g. substaging of pT1 should be attempted). Further optimisation, however, is required. No particular method of substaging pT1 is formally recommended. In this review, these modifications are discussed, as well as points, which require further study and optimisation.

En bloc resection improves the identification of muscularis mucosae in non-muscle invasive bladder cancer

PURPOSE

The T1 substage, according to the relationship between muscularis mucosae (MM) and tumors, is a promising prognostic factor for T1 bladder cancer. However, the identification rate of MM is low in specimens, and it is, therefore, not widely used in clinical practice. In this study, we investigated whether en bloc resection of non-muscle invasive bladder cancer (NMIBC) could improve the identification of muscularis mucosae (MM), which may further accurate identification of the T1 substage.

PATIENTS AND METHODS

Specimens from 158 patients with primary NMIBC were retrospectively reviewed by two independent pathologists to assess the presence of MM and stratify the T1 substage. Of 158 specimens, 70 specimens were obtained via TURBt with a plasma kinetic loop and 88 were obtained via front-firing potassium-titanyl-phosphate (KTP) green-light laser en bloc resection. Univariable and multivariable logistic regression models were used to analyze the relationship between the clinical characteristics and the presence of MM.

RESULTS

The mean age was 58.22 years (range 18-85 years). Multivariable logistic regression analysis showed that the KTP laser resection method was associated with the presence of MM in specimens (P = 0.008). In addition, tumors with smaller sizes, which could also be en bloc resected with TURBt (e.g., ≤1 cm), had a higher presence of MM (P = 0.047).

CONCLUSIONS

En bloc resection improves the identification rate of MM, which may enhance the accurate identification of the T1 substage.

Contemporary Grading and Staging of Urothelial Neoplasms of the Urinary Bladder: New Concepts and Approaches to Challenging Scenarios

Grading and staging of urothelial neoplasm are the most crucial factors in risk stratification and management; both necessitate optimal accuracy and consistency. Several updates and recommendations have been provided though recent publications of the 4th edition of the World Health Organization classification, the 8th edition of the American Joint Committee on Cancer staging system, and the International Consultation on Urological Diseases-European Association of Urology updates on bladder cancer. Updates and recent studies have provided better insights into and approaches to the challenging scenarios in grading and staging of urothelial neoplasm; however, there remain aspects that need further investigation and refinement.

Urinary Bladder Pathology: World Health Organization Classification and American Joint Committee on Cancer Staging Update

Context.—

Since the publication of the previous World Health Organization (WHO) Classification of Tumours on the Pathology and Genetics of Tumours of the Urinary System and Male Genital Organs in 2004, significant new knowledge has been generated regarding the pathology and genetics of bladder neoplasia. Publication of the 2016 WHO “Blue Book” has codified that new data into updated recommendations for classification and prognostication. Similarly, the recent release of the 8th edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual, which was implemented in January 2018, has also addressed staging criteria for bladder cancer in several unique settings to clarify their application.

Objective.—

To highlight subtle changes within the recent WHO and AJCC publications that may affect daily surgical pathology practice.

Data Sources.—

Peer-reviewed published literature, the 2016 WHO Classification of Tumours of the Urinary System and Male Genital Organs, and the 8th edition of the AJCC Cancer Staging Manual were reviewed.

Conclusions.—

Selected changes and/or clarifications are discussed and include classification of flat and papillary urothelial neoplasia, select variant patterns of invasive urothelial carcinoma, staging of invasive carcinoma in bladder diverticula, and staging of carcinomas involving the prostate gland.

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.

Metric substage according to micro and extensive lamina propria invasion improves prognostics in T1 bladder cancer

BACKGROUND

Reliable prognosticators for T1 bladder cancer (T1BC) are urgently needed.

OBJECTIVE

To compare the prognostic value of 2 substage systems for T1BC in patients treated by transurethral resection (TUR) and adjuvant bacillus Calmette-Guérin therapy.

DESIGN, SETTING, AND PARTICIPANTS

The slides of 601 primary T1BCs from four institutes were reviewed by 2 uropathologists and substaged according to 2 classifications: metric substage according to T1 microinvasive (T1m-lamina propria invasion <0.5mm) and T1 extensive invasive (pT1e-invasion ≥ 0.5mm), and according to invasion of the muscularis mucosae (MM) (T1a-invasion above or into MM/T1b).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Multivariable analyses for progression-free (PFS) and cancer-specific survival (CSS) were performed including substage, size, multiplicity, carcinoma in situ, sex, age, WHO-grade 1973, and WHO-grade 2004 as variables.

RESULTS

Median follow-up was 5.9 years (interquartile range: 3.3-9.0). Progression to T2BC was observed in 148 (25%) patients and 94 (16%) died of BC. The MM was not present at the invasion front in 135 (22%) of tumors. Slides were substaged as follows: 213 T1m and 388 T1e and 281 T1a and 320 T1b. On multivariable analysis, T1m/e substage and WHO 1973 grade were the strongest prognosticators for PFS (hazard ratio [HR] = 3.8 and HR = 1.8) and CSS (HR = 2.7 and HR = 2.6), respectively. Other prognostic factors for CSS were age (HR = 1.03), and tumor size (HR = 1.8). Substage according to MM-invasion was not significant. Our study was limited by its retrospective design and that standard re-TUR was not performed if TUR was macroscopically complete and muscularis propria was present in resected specimens.

CONCLUSIONS

Metric substaging of T1BC was possible in all cases of 601 T1BC patients and it was a strong independent prognosticator of both PFS and CSS.

A practical guide to bladder cancer pathology

Pathological assessment of bladder cancer is becoming an increasingly complex task owing to the growing availability of molecular data for different histological subtypes and the appreciation of their importance in determining outcomes of neoadjuvant chemotherapy. Urologists are aware of the need to closely collaborate with pathologists, and comprehensive sharing of information is crucial to achieve optimal patient management. Numerous steps towards this goal have been made during the past years. Important advances in the assessment and reporting of grading and staging, especially substaging of pT1 urothelial carcinomas, have been made. As part of the International Collaboration on Cancer Reporting (ICCR), an international expert group has suggested worldwide reporting standards for urothelial lesions. Nevertheless, several issues remain unresolved, for example, regarding the reporting of heterogeneous lesions and substaging as well as the gross handling and the reporting for lymphadenectomy specimens. During the past few years, major insights have been gained into the molecular changes that occur during bladder cancer development, but a consensus on how to integrate these data into daily practice has not been achieved.

Stalk versus base invasion in pT1 papillary cancers of the bladder: improved substaging system predicting the risk of progression

AIMS

Pathological stage pT1 bladder cancers constitute a clinically heterogeneous group. However, current staging guidelines for superficially invasive cancers do not acknowledge the variability in type and extent of lamina propria invasion in papillary urothelial carcinomas (PUCs), and historically proposed substaging systems showed either high interobserver variation or limited value in predicting patient outcomes. The aim of this study was to reappraise pT1 PUC substaging, with the objective of identifying a novel scheme that is reproducible and prognostically meaningful.

METHODS AND RESULTS

pT1 PUCs diagnosed during 1999-2015 were retrospectively reviewed and characterized as focal invasion confined to the papillary stalk, focal invasion of the tumour base, or extensive invasion of the tumour base. Cases with concurrent flat carcinoma in situ, angiolymphatic invasion, absent muscularis propria or clinically advanced disease were excluded. We calculated cumulative incidence rates of recurrence, progression and death by tumour subtype, and evaluated differential risks by using log-rank tests and Kaplan-Meier curves stratified by type and extent of invasion. Among 62 patients satisfying the inclusion criteria, 22 of 29 patients with base-extensive invasion progressed, whereas four of 13 with base-focal and none of 20 with stalk-only invasion progressed. There was strong evidence that base-extensive patients had a higher risk of progression and death resulting from bladder cancer than base-focal or stalk-only patients (P < 0.0001). However, tumour subtype was not significantly associated with risk of recurrence (P = 0.21).

CONCLUSIONS

We propose an innovative substaging approach for reporting the site and extent of lamina propria invasion in patients with pT1 PUC, allowing patient stratification for risk of progression.

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.

Expression of human epidermal growth factor receptor 2 in bladder urothelial carcinoma

BACKGROUND

Urothelial bladder carcinoma (UBC) is one of the most prevalent cancers in men worldwide. Human epidermal growth factor receptor 2 (HER2) expression has been detected in a wide range of urothelial carcinoma. Despite many reports in the literature, the prognostic significance of this overexpression remains unclear. The aim of this study was to assess the expression of HER2 in urothelial bladder carcinomas and its association with clinical and pathological parameters.

METHODS

103 cases of UBC were diagnosed in our department between January 2014 and December 2015. The tumor specimens obtained by transurethral resection or cystectomy were evaluated by immunohistochemistry using HER2 antibody.

RESULTS

HER2 protein overexpression was present in 11.7% of cases and associated with tumor grade (p = 0.003) and pathological stage (p = 0.015). In multivariate analysis, HER2 overexpression was associated only with tumor grade (P = 0.04).

CONCLUSION

HER2 protein overexpression is noted in patients with high grade cancer. This expression may select patients for anti HER2 targeted therapy. Future larger and prospective studies will verify the frequency of HER2 alteration and the role of HER2 in the aggressive behavior.

Morphologic and Molecular Characteristics of Bladder Cancer

Bladder cancer is the fourth most common cancer in men, and is associated with significant morbidity and mortality. Pathologic evaluation of urothelial cancers relies predominantly on histomorphologic features but can be aided in a small subset of cases by immunohistochemical analyses. Distinction of papillary versus flat lesions, low-grade versus high-grade cytology, and histologic variants and the presence or absence of invasive tumor is important for proper clinical management. Advances in the molecular alterations associated with the various subtypes of urothelial carcinoma have been made but such studies are ongoing.

The prognostic role of lymphovascular invasion in urothelial carcinoma of the bladder

Outcome prediction in patients with bladder cancer has improved through the development of nomograms and predictive models. However, integration of further characteristics such as lymphovascular invasion (LVI) might increase the accuracy and clinical utility of these instruments. Assessment and reporting of LVI in specimens from transurethral resection of the bladder tumour (TURBT) or biopsy in patients with non-muscle-invasive bladder cancer (NMIBC) or muscle-invasive bladder cancer (MIBC) might enable improved staging, prognostication and clinical decision-making. In NMIBC, presence of LVI in TURBT and biopsy samples seems to be associated with understaging and increased risks of disease recurrence and progression. In MIBC, presence of LVI is associated with features of aggressive disease and predicts recurrence and survival. Integration of LVI status into predictive models might aid clinical decision-making regarding intravesical instillation schedules and regimens, early radical cystectomy in patients with high-grade T1 disease and perioperative chemotherapy. However, LVI assessment is hampered by insufficient reproducibility and reliability, lack of routine evaluation and limited concordance between findings in TURBT and radical cystectomy specimens. Standardization of the pathological criteria defining LVI is warranted to improve its reporting in routine clinical practice and its utility as a care-changing prognostic marker.

Usefulness of pT1 substaging in papillary urothelial bladder carcinoma

Background

When treating bladder cancer patients, the most significant problems usually concern cases with high-grade non-muscle-invasive carcinoma, and a better understanding of which patients would benefit from early radical cystectomy is urgently needed. The uropathology community is seeking more user-friendly approaches to distinguishing between T1 cancers exhibiting different types of clinical behavior.

Methods

After a retrospective review, we selected a group of 314 patients who underwent transurethral resection of the bladder (TURB) and were diagnosed with high-grade urothelial carcinoma staged as T1. Three different substaging systems were applied: one was the anatomy-based T1 a/b; and two involved micrometric thresholds of either 0.5 mm of invasion (as proposed by van Rhijn et al.), or 1 mm of invasion (as proposed in the present study). Early reTUR (repeated transurethral resection) was performed in 250 patients, and the same substaging approaches were applied to cases of T1.

Results

It proved feasible to apply the 1 mm substaging system in 100 % of cases, the van Rhijn system in 100 %, and the anatomy-based method (T1 a/b) in 72.3 % of cases. At a mean follow-up of 46 months, the recurrence-free survival rate was significantly better (p < 0.001) in the group that underwent reTUR, while none of the three substaging systems reliably predicted recurrences. The 1 mm did seem promising, however, as a threshold for predicting progression, reaching statistical significance in the Kaplan Meier estimates (p < 0.04).

Conclusion

Our study shows that micrometric substaging is feasible in this setting and should be extended to include any early reTUR to complete the substaging done after the first TURB. It can also provide helpful prognostic information.

Clinical Significance of Substaging and HER2 Expression in Papillary Nonmuscle Invasive Urothelial Cancers of the Urinary Bladder

The study aimed to verify the prognostic utility, therapeutic application and clinical benefits of tumor substaging and HER2 status in papillary non-muscle invasive bladder cancer (NMIBC). Select NMIBC transurethral resection specimens from 141 patients were used to construct tissue microarrays for assessing the substaging, HER2 protein expression by immunohistochemistry (HER2-IHC) and gene amplification by dual-color silver in situ hybridization (HER2-SISH). Substages were identified by the differing depth of tumor invasion (pTa / pT1a / pT1b / pT1c). HER2 protein expression was semiquantitatively analyzed and grouped into negative (score 0, 1+) and positive (score 2+, 3+). Other clinicopathological variables were also investigated. For NMIBC, HER2-IHC and HER2-SISH showed positive results in 6/141 (4.3%) and 4/141 (2.8%) respectively, which correlated well with tumor substaging. In multivariate analysis, substaging, HER2-IHC, and HER2-SISH were found to be independent predictors of progression-free survival (P < 0.001, P < 0.001, P = 0.031). HER2-IHC was the sole independent predictor of recurrent free survival in NMIBC (P = 0.017). It is suggested that tumor substaging and HER2 status are independent predictive markers for tumor progression or recurrence, and thus could be included in diagnostic and therapeutic management for NMIBC.

Exploration of risk factors predicting outcomes for primary T1 high-grade bladder cancer and validation of the Spanish Urological Club for Oncological Treatment scoring model: Long-term follow-up experience at a single institute

OBJECTIVE

To determine the prognostic factors of primary T1 high-grade bladder cancer and to validate the Spanish Urological Club for Oncological Treatment model in Japanese patients with T1 high-grade bladder cancer treated at a single institution.

METHODS

Records of 106 patients with T1 high-grade bladder cancer treated from 1998 to 2013 were retrospectively reviewed. Variables included various clinicopathological parameters, including lymphovascular invasion and tumor growth pattern at the invasion front. Recurrence-free survival and progression-free survival were analyzed. Multivariate Cox proportional regression analysis was used to verify the prognostic significance of the variables. Scores for recurrence and progression were calculated using the Spanish Urological Club for Oncological Treatment model.

RESULTS

Of 106 patients, 44 (42%) had recurrence and 16 (15%) developed progression after a median (interquartile range) follow-up period of 54 months (range 32-81 months). Non-papillary shape was the only independent predictor for recurrence, while broad-based tumor stalk and infiltrative tumor growth pattern at the invasion front were determined to be independent predictors for progression. Stratification of patients according to the number of progression risk factors yielded hazard ratios of 10.1 and 13.1 in patients having one and two risks, respectively, compared with those without any risks. The Spanish Urological Club for Oncological Treatment model successfully stratified our patients with a trend toward different probabilities of recurrence and progression.

CONCLUSIONS

The results of the present study might be helpful for counseling certain patients towards intensive treatment, such as radical cystectomy and/or platinum-based systemic chemotherapy. In addition, the Spanish Urological Club for Oncological Treatment model might be applicable to Japanese patients with T1 high-grade bladder cancer.

High-risk nonmuscle invasive bladder cancer

Please also verify that the expansion of HGT1 is OK as set: The risk of progression for high-grade T1 (HGT1) cancer has been recently established at 21% using updated information on large series and a meta-analysis. These outcomes are better than those classically expected supporting the rule of thirds for HGT1. The main limitation of this subgroup is that most studies are retrospective observational studies, which, compared with randomized controlled trials, are subject to various selection biases, carrying a higher risk of uncontrolled confounding factors, with potential preferential reporting of positive findings.

Prognostic factors in urothelial carcinoma of the bladder: histologic and molecular correlates

Histologic characterization of urothelial carcinoma remains the most important factor for determining a patient's prognosis and treatment regimen. However, challenges remain in accurately staging and grading many tumors, and substaging remains controversial. Recently, significant insight has been gained into the molecular pathogenesis of bladder cancer that may aid in further characterizing urothelial carcinoma. Many molecular biomarkers have been clinically validated, and some have been shown to provide more prognostic information than histology alone. In addition, a subset of these markers may even represent targets for molecular therapy. Here, we review histologic staging and grading of urothelial carcinoma, as well as discuss many of the clinically relevant molecular markers. As each urothelial carcinoma likely represents a unique biological entity, the need for complete histologic and molecular characterization of these tumors is necessary as we enter the age of personalized medicine.