Reexamining treatment of high-grade T1 bladder cancer according to depth of lamina propria invasion: a prospective trial of 200 patients

Unlocking the Potential of Adequate Bacillus Calmette-Guérin Immunotherapy in Very-high-risk Non-muscle-invasive Bladder Carcinoma: A Multicenter Analysis of Oncological Outcomes and Risk Dynamics

BACKGROUND

The European Association of Urology (EAU) recommends discussing upfront radical cystectomy for all patients with very high risk (VHR) non-muscle-invasive bladder carcinoma (NMIBC), but the role of bacillus Calmette-Guérin (BCG) treatment remains controversial.

OBJECTIVE

To analyze oncological outcomes in VHR NMIBC patients (EAU risk groups) treated with adequate BCG.

DESIGN, SETTING, AND PARTICIPANTS

A multi-institutional retrospective study involving patients with VHR NMIBC who received adequate BCG therapy from 2007 to 2020 was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A survival analysis estimated recurrence-free survival (RFS), progression-free survival (PFS), and the cumulative incidence of cancer-specific mortality (CSM) after accounting for other causes of mortality as competing risk events and of the overall mortality (OM). Conditional survival probabilities for 0-4 yr without events were computed. Cox regression assessed the predictors of oncological outcomes.

RESULTS AND LIMITATION

A total of 640 patients, with a median 47 (32-67) mo follow-up for event-free individuals, were analyzed. High-grade RFS and PFS at 5 yr were 53% (49-57%) and 78% (74-82%), respectively. The cumulative incidence of CSM and OM at 5 yr was 13% (10-16%) and 16% (13-19%), respectively. Conditional RFS, PFS, overall survival, and cancer-specific survival at 4 yr were 91%, 96%, 87%, and 94%, respectively. Cox regression identified tumor grade (hazard ratio [HR]: 1.54; 1.1-2) and size (HR: 1.3; 1.1-1.7) as RFS predictors. Tumor multiplicity predicted RFS (HR: 1.6; 1.3-2), PFS (HR: 2; 1.2-3.3), and CSM (HR: 2; 1.2-3.2), while age predicted OM (HR: 1.48; 1.1-2).

CONCLUSIONS

Patients with VHR NMIBC who receive adequate BCG therapy have a more favorable prognosis than predicted by EAU risk groups, especially among those with a sustained response, in whom continuing maintenance therapy emerges as a viable alternative to radical cystectomy.

PATIENT SUMMARY

Our research shows that a sustained response to bacillus Calmette-Guérin in patients can lead to favorable outcomes, serving as a viable alternative to cystectomy for select cases.

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.

A 10-year renaissance of en bloc resection of bladder tumors (ERBT): Are we approaching the peak or is it back to the trough?

BACKGROUND

The number of studies suggesting that en bloc resection of bladder tumor (ERBT) is superior to transurethral resection of bladder tumor (TURBT) for non-muscle-invasive bladder cancer (NMIBC) management is growing. The aim of this review is to discuss the features of these procedures and to determine the prospects of en bloc in NMIBC management.

MATERIALS AND METHODS

We conducted a literature search using two databases (Medline and Scopus) and included any research which reported ERBT outcomes.

RESULTS

The lasers with minimal tissue penetration depth are becoming the main tool for ERBT. Unfortunately, most of the systematic reviews continue to be characterized by high heterogeneity. However, recent studies indicate that ERBT may have the edge when it comes to the detrusor muscle rate and the quality of the histological specimen. ERBT may favor in terms of in-field relapse, but its rate in the studies varies greatly. As for out-field relapse-free survival, the data are still lacking. The strongest evidence supports that ERBT is superior to TURBT in complications rate (bladder perforation). ERBT is feasible irrespective to tumor size and location.

CONCLUSIONS

ERBT has gained in momentum with the increasingly widespread use of this kind of laser surgery. The introduction of novel sources (TFL and Thulium:YAG pulsed laser) will definitely affect how the field develops and will result in further improvements in safety and precision. The latest trials make us more certain in our belief that ERBT will be beneficial in terms of histological specimen quality, relapse rate and complications rate.

[Interpretation of biopsy material after transuretral and laser en bloc resection of non-muscle-invasive bladder cancer]

Bladder cancer is one of the most common onco-urological diseases, ranked second in frequency among all tumors of the urinary system after prostate cancer. At the time of detection of the primary tumor, approximately 75% of patients have no invasion into the muscularis layer (non-muscle-invasive carcinoma), with tumor growth limited to the basal membrane (stage Ta) or submucosal base (stage T1). Removal of the tumor in a «unified block» (laser en-bloc resection or L-ERBT), unlike routine transurethral resection, allows to obtain qualitative biopsy material for precise pathomorphological staging of the tumor process. In order to accurately stratify a patient into one or another risk group, verification of the following morphological parameters is required: degree of tumor differentiation and its malignancy, depth of invasion, foci of carcinoma in situ at resection margins, presence or absence of lymphovascular invasion. Identification of tumor variant histology is also recommended. Information on presence or absence of detrusor elements in the specimen is necessary in the morphological report, as this parameter is considered as a criterion of radically performed tumor removal. According to ICCR recommendations (International Collaboration on cancer reporting), it is recommended to use subclassification of T1 stage using all possible criteria: volume and/or depth of invasion (assessed in mm), and/or width of invasion «spot» (assessed in mm), and/or involvement of anatomical structure - muscularis mucosae. Full morphological examination of the material obtained during the primary resection of the tumor is an important step in the diagnosis and treatment of bladder cancer, as it allows to stratify the patient into one or another risk group and, accordingly, allows to develop a personalized postoperative management.

Treatment Outcomes of High-Risk Non-Muscle Invasive Bladder Cancer (HR-NMIBC) in Real-World Evidence (RWE) Studies: Systematic Literature Review (SLR)

Background

To date, there has been limited synthesis of RWE studies in high-risk non-muscle invasive bladder cancer (HR-NMIBC). The objective of this research was to conduct a systematic review of published real-world evidence to better understand the real-world burden and treatment patterns in HR-NMIBC.

Methods

An SLR was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with the scope defined by the Population, Intervention Comparators, Outcomes, and Study design (PICOS) criteria. EMBASE, MEDLINE, and Cochrane databases (Jan 2015–Jul 2020) were searched, and relevant congress abstracts (Jan 2018–Jul 2020) identified. The final analysis only included studies that enrolled ≥100 patients with HR-NMIBC from the US, Europe, Canada, and Australia.

Results

The SLR identified 634 RWE publications in NMIBC, of which 160 studies reported data in HR-NMIBC. The average age of patients in the studies was 71 years, and 79% were males. The rates of BCG intravesical instillations ranged from 3% to 86% (29–95% for induction and 8–83% for maintenance treatment). Five-year outcomes were 17–89% recurrence-free survival (longest survival in patients completing BCG maintenance), 58–89% progression-free survival, 71–96% cancer-specific survival (lowest survival in BCG-unresponsive patients), and 28–90% overall survival (lowest survival in patients who did not receive BCG or instillation therapy).

Conclusion

BCG treatment rates and survival outcomes in patients with HR-NMIBC vary in the real world, with better survival seen in patients completing maintenance BCG, responding to treatment, and not progressing to muscle-invasive disease. There is a need to better understand the factors associated with BCG use and discontinuation and for an effective treatment that improves outcomes in HR-NMIBC. Generalization of these results is limited by variations in data collection, reporting, and methodologies used across RWE studies.

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.

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.

Feasibility and accuracy of pathological diagnosis in en-bloc transurethral resection specimens versus conventional transurethral resection specimens of bladder tumour: evaluation with pT1 substaging by 10 pathologists

AIMS

En-bloc transurethral resection (TUR) of bladder tumour (ERBT) is designed to provide more accurate pathological diagnosis of specimens than conventional TUR of bladder tumour (cTURBT). Some studies have reported that T1 bladder cancer substage could be a prognostic factor in assessing tumour progression, but such substaging has not been widely adopted because of problems with pathological diagnosis using cTURBT specimens. The aim of this study was to evaluate the possible advantages of en-bloc TUR specimens in T1 substaging following assessment by a panel of 10 pathologists.

METHODS AND RESULTS

We assessed the substages in 123 patients (cTURBT, n = 91; ERBT, n = 32) who were diagnosed with pT1 bladder cancer. We randomly selected 10 ERBT specimens and 10 cTURBT specimens with cancer invasion areas equivalent to those of their corresponding ERBT specimens. Ten pathologists performed pT1 substaging for pT1a/b/c and pT1m/e in 20 patients (cTURBT, n = 10; ERBT, n = 10). We evaluated diagnostic times and rates of diagnostic concordance among these pathologists, comparing cTURBT and ERBT. The median diagnostic times per slide were 87.7 s [interquartile range (IQR) 71.9-109.2 s) for cTURBT and 54.7 s (IQR 46.0-59.6 s) for ERBT (P = 0.009). The rate of diagnostic concordance was significantly better for ERBT specimens. For pT1a/b/c, the median concordance rates were 50% for cTURBT and 80% for ERBT (P = 0.02); for pT1m/e, the median concordance rates were 70% for cTURBT and 90% for ERBT (P = 0.05). For pT1a/b/c, the average κ-values between the pathologist and the standard diagnosis were 0.04 for cTURBT and 0.47 for ERBT.

CONCLUSIONS

The use of ERBT specimens shortened the diagnostic time and minimised interobserver variability for T1 substaging compared with the use of cTURBT specimens.

Prognosis of patients with T1 bladder cancer after en bloc transurethral resection of bladder tumor stratified by invasion to the level of the muscularis mucosa

PURPOSE

To evaluate the prognosis of patients with pT1 bladder cancer who underwent en bloc resection of bladder tumors (ERBTs), stratified by invasion to the muscularis mucosa (MM) level.

METHODS

Among 64 specimens obtained by ERBT with bipolar energy from patients with pT1 bladder cancer, MM was detected in 61 specimens. Thus, 61 specimens were included in this retrospective study. Patients were stratified by invasion to the MM level (pT1a, invasion above the MM level; pT1b, invasion within the MM level; and pT1c, invasion beyond the MM level). In specimens with discontinuous MM, invasion to the MM level was predicted from the dispersed MM in the specimen. The primary endpoints were progression-free survival (PFS) and cancer-specific survival (CSS).

RESULTS

Progression occurred in 2/39 patients with pT1a (5.1%), 1/6 patients with pT1b (16.7%), and 6/16 patients with pT1c cancer (37.5%). Cancer death occurred in 1/39 patients with pT1a (2.6%), 0/7 patients with pT1b, and 3/16 patients with pT1c cancer (18.8%). Patients with pT1a or pT1b cancer had a significantly better prognosis than those with pT1c cancer. On univariate analysis, tumor size ≥ 3 cm and pT1c were significantly associated with shorter PFS. On multivariate analysis, only pT1c was independently associated with shorter PFS.

CONCLUSION

This is the first study evaluating the prognosis by T1 substaging based on invasion to the MM level using ERBT specimens. ERBT provided high-quality specimens for diagnosing the MM and showed poor prognosis in pT1c bladder cancer. ERBT could be an appropriate surgical approach for an accurate diagnosis and prognosis of the T1 bladder cancer substage.

Transcriptomic analysis of micropapillary high grade T1 urothelial bladder cancer

No consensus currently exist on the optimal treatment of patients with high-risk nonmuscle invasive (HGT1) micropapillary variant of bladder cancer (MPBC). Transcripsome analysis may allow stratification of MPBC-HGT1 enabling prediction of recurrence and guide therapeutic management for individual patients. Whole transcriptome RNA-Sequencing of tumors from 23 patients with MPBC-HGT1 and 64 conventional urothelial carcinomas (cUC) (reference set) was performed. Differentially expressed genes between MPBC-HGT1 and cUC-HGT1 were explored. Cox proportional hazard models and Kapplan–Meier methods were used to assess the relation between time to progression (TTP) and individual gene expression adjusting for clinical covariates. Over 3000 genes were differentially expressed in MPBC-HGT1 as compared with cUC-HGT1 and a 26-gene signature is characteristic of MPBC within HGT1. A set of three genes; CD36, FAPB3 and RAETE1; were significantly associated with TTP. High expression of FABP3 and CD36 were associated with shorter TTP (p = 0.045 and p = 0.08) as was low expression of RAET1E (p = 0.01). Our study suggest that a 26-gene signature can define MPBC-HGT1 within conventional urothelial carcinomas. A prognostic risk index of three genes (FABP3, CD36 and RAET1E) was found to be associated with shorter TTP and may help classify a group of patients with MPBC-HGT1 with high-risk of early progression. These observations might have implications in terms of radical cystectomy recommendation in MPBC patients.

Genomic Predictors of Good Outcome, Recurrence, or Progression in High-Grade T1 Non-Muscle-Invasive Bladder Cancer

High-grade T1 (HGT1) bladder cancer is the highest risk subtype of non-muscle-invasive bladder cancer with unpredictable outcome and poorly understood risk factors. Here, we examined the association of somatic mutation profiles with nonrecurrent disease (GO, good outcome), recurrence (R), or progression (PD) in a cohort of HGT1 patients. Exome sequencing was performed on 62 HGT1 and 15 matched normal tissue samples. Both tumor only (TO) and paired analyses were performed, focusing on 95 genes known to be mutated in bladder cancer. Somatic mutations, copy-number alterations, mutation load, and mutation signatures were studied. Thirty-three GO, 10 R, 18 PD, and 1 unknown outcome patients were analyzed. Tumor mutational burden (TMB) was similar to muscle-invasive disease and was highest in GO, intermediate in PD, and lowest in R patients (P = 0.017). DNA damage response gene mutations were associated with higher TMB (P < 0.0001) and GO (P = 0.003). ERCC2 and BRCA2 mutations were associated with GO. TP53, ATM, ARID1A, AHR, and SMARCB1 mutations were more frequent in PD. Focal copy-number gain in CCNE1 and CDKN2A deletion was enriched in PD or R (P = 0.047; P = 0.06). APOBEC (46%) and COSMIC5 (34%) signatures were most frequent. APOBEC-A and ERCC2 mutant tumors (COSMIC5) were associated with GO (P = 0.047; P = 0.0002). pT1b microstaging was associated with a genomic cluster (P = 0.05) with focal amplifications of E2F3/SOX4, PVRL4, CCNE1, and TP53 mutations. Findings were validated using external public datasets. These findings require confirmation but suggest that management of HGT1 bladder cancer may be improved via molecular characterization to predict outcome. SIGNIFICANCE: Detailed genetic analyses of HGT1 bladder tumors identify features that correlate with outcome, e.g., high mutational burden, ERCC2 mutations, and high APOBEC-A/ERCC2 mutation signatures were associated with good outcome.

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.

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.

Salvage Therapies for Non-muscle-invasive Bladder Cancer: Who Will Respond to Bacillus Calmette-Guérin? Predictors and Nomograms

The best predictors of response to intravesical immunotherapy are tumor grade and stage, tumor recurrence pattern, nomograms, panels of urinary cytokines, and fluorescent in situ hybridization patterns of urine cytology examinations. Future investigations on predictors of Bacillus Calmette-Guérin efficacy are needed to better select those patients who will really benefit from a conservative treatment. Hardly any of the proposed nomograms were designed to precisely predict the outcome of Bacillus Calmette-Guérin immunotherapy. A new nomogram for NMIBC recurrence and progression based on all non-muscle-invasive bladder cancer subgroups would include factors already proven in cancer prognosis and prediction.

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.

T1 bladder cancer: current considerations for diagnosis and management

Stage T1 bladder cancers invade the lamina propria of the bladder and, despite sharing many of the genetic features of muscle-invasive bladder cancers, are classified as non-muscle-invasive or 'superficial' tumours. Yet, patients with T1 bladder cancer have an overall mortality of 33% and a cancer-specific mortality of 14% at three years after diagnosis, suggesting that these patients have a high risk of progression and, accordingly, require meticulous surgery, endoscopic surveillance and clinical decision-making. We hypothesize that the variability in the outcomes of patients with T1 bladder cancer is a result of both tumour heterogeneity and pathological staging, as well as inconsistencies in risk stratification, endoscopic resection and schedules of delivery of BCG. Owing to limitations in clinical staging, patients with T1 bladder cancer are at risk of both undertreatment with persistent use of BCG despite recurrence, and overtreatment with early cystectomy. Understanding the molecular features of T1 bladder cancers and how they respond to BCG therapy could improve biomarkers for risk stratification to align therapy with biological risk.

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.

Does it matter whether a T1 high-grade tumor is molecularly classified?

A 58-yr-old male, 20 pack-year smoker, with hypertension was diagnosed with a single left-side high-grade papillary tumor with peritumoral carcinoma in situ, but no tumor was visible outside the bladder. En bloc resection was performed, and repeat transurethral resection of the bladder at 4 wk found no residual tumor. He was prescribed bacillus Calmette-Guérin (BCG) plus maintenance therapy, and cystoscopy at 9 mo found a T1b high-grade tumor, this time right sided. Is it important that the tumor should be molecularly characterized before a treatment decision is made, or is clinicopathologic characterization still the only viable option at this time? PATIENT SUMMARY: We discussed how new methods in pathology may help us find molecular structures that would help clinicians decide safely between cystectomy and conservative bladder-sparing strategies. The primary superficially infiltrative tumor and its similar recurrence 9 mo later were categorized based on standard clinical criteria, but here we discuss whether recently discovered methods for defining the molecular structure of tumors could mean that more bladder-preserving treatments might be an option.

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.

Communication Of Cancer Cells And Lymphatic Vessels In Cancer: Focus On Bladder Cancer

Bladder cancer is one of the most commonly diagnosed cancers worldwide and causes the highest lifetime treatment costs per patient. Bladder cancer is most likely to metastasize through lymphatic ducts, and once the lymph nodes are involved, the prognosis is poorly and finitely improved by current modalities. The underlying metastatic mechanism for bladder cancer is thus becoming a research focus to date. To identify relevant published data, an online search of the PubMed/Medline archives was performed to locate original articles and review articles regarding lymphangiogenesis and lymphatic metastasis in urinary bladder cancer (UBC), and was limited to articles in English published between 1998 and 2018. A further search of the clinical trials.gov search engine was conducted to identify both trials with results available and those with results not yet available. Herein, we summarized the unique mechanisms and biomarkers involved in the malignant progression of bladder cancer as well as their emerging roles in therapeutics, and that current data suggests that lymphangiogenesis and lymph node invasion are important prognostic factors for UBC. The growing knowledge about their roles in bladder cancers provides the basis for novel therapeutic strategies. In addition, more basic and clinical research needs to be conducted in order to identify further accurate predictive molecules and relevant mechanisms.

Does restaging transurethral resection of bladder tumour influence outcomes in patients treated with BCG immunotherapy? 491 cases in 20 years' experience

Introduction

Bladder cancer is one of the most common malignancies worldwide.

Aim

To analyse the influence of restaging transurethral resection of bladder tumour (reTURB) on outcomes in patients treated with BCG immunotherapy.

Material and methods

We analysed a database of 491 patients who were treated in a Bacillus Calmette-Guérin (BCG) outpatient department between 1998 and 2016. A minimum of 12 months of follow-up was required. The study included 235 patients with a history of the reTURB procedure and 256 patients without reTURB. The patients were analysed in terms of recurrence-free (RFS), progression-free (PFS), cancer-specific and overall survival.

Results

The RFS was significantly higher in the reTURB group for both general and subgroup analysis (T1HG, TaHG). The PFS was significantly higher in the reTURB group for both general and subgroup analysis (TaHG). In patients without lamina muscularis in the specimen there was a greater improvement in RFS due to the reTURB procedure than for other patients. ReTURB performed in T1 tumours with massive lamina propria infiltration had a positive influence on RFS. In patients with reTURB the presence of focal invasion was related to lower risk of progression. Both overall and cancer-specific survival were significantly improved by the reTURB procedure in T1HG and HG tumours.

Conclusions

This study highlights the importance of reTURB. It was found that the patients with TaHG tumours benefited the most in terms of RFS, PFS and cancer-specific survival. It was also demonstrated that massive lamina propria infiltration in T1 tumours is associated with the worst outcomes.

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.

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.

Comparative differences between T1a/b and T1e/m as substages in T1 urothelial carcinoma of the bladder

Objective

To evaluate the prognostic value of the depth of lamina propria invasion in patients with T1 bladder cancer and to display comparative differences between the T1a/b and T1e/m substaging systems.

Patients and Methods

This study included 106 patients with primary stage T1 urothelial bladder tumours who underwent surgery between January 2009 and December 2014. Pathologic specimens were re-evaluated to confirm the diagnosis of T1 and substaging by the same pathologist using two systems: T1a and T1b, and T1m and T1e. Age, tumour size, multiplicity, associated carcinoma in situ, tumour grade, and T1 substaging system were investigated to detect the relation between disease progression and recurrence.

Results

The recurrence rate was 52% for T1a (n=42) vs. 76% for T1b (n=20) (p=0.028) and 55% for T1m (n=32) vs. 62% for T1e (n=30), respectively (p=0.446). There was no significant difference between the substaging groups for disease progression: T1a (n=12, 15%) vs. T1b (n=7, 27%), and T1m (n=8, 13.8%) vs. T1e (n=11, 23%) (p>0.05). In the multivariate analysis, tumour size >3 cm (p=0.008), multiplicity (p=0.049), and substaging T1b (p=0.043) were independent predictive factors for tumour recurrence. According to the Kaplan-Meier actuarial method, recurrence-free survival was significantly different in patients with pT1a tumours compared with those with pT1b tumours (p=0.033).

Conclusions

Substaging T1 provides a prediction of disease recurrence. Regarding recurrence, T1a/b substaging can provide better knowledge of disease behaviour because it is predicted as more superior than T1 m/e, and it can help in determining the requirement for early cystectomy.

The World Health Organization 1973 classification system for grade is an important prognosticator in T1 non-muscle-invasive bladder cancer

OBJECTIVES

To compare the prognostic value of the World Health Organization (WHO) 1973 and 2004 classification systems for grade in T1 bladder cancer (T1-BC), as both are currently recommended in international guidelines.

PATIENTS AND METHODS

Three uro-pathologists re-revised slides of 601 primary (first diagnosis) T1-BCs, initially managed conservatively (bacille Calmette-Guérin) in four hospitals. Grade was defined according to WHO1973 (Grade 1-3) and WHO2004 (low-grade [LG] and high-grade [HG]). This resulted in a lack of Grade 1 tumours, 188 (31%) Grade 2, and 413 (69%) Grade 3 tumours. There were 47 LG (8%) vs 554 (92%) HG tumours. We determined the prognostic value for progression-free survival (PFS) and cancer-specific survival (CSS) in Cox-regression models and corrected for age, sex, multiplicity, size and concomitant carcinoma in situ.

RESULTS

At a median follow-up of 5.9 years, 148 patients showed progression and 94 died from BC. The WHO1973 Grade 3 was negatively associated with PFS (hazard ratio [HR] 2.1) and CSS (HR 3.4), whilst WHO2004 grade was not prognostic. On multivariable analysis, WHO1973 grade was the only prognostic factor for progression (HR 2.0). Grade 3 tumours (HR 3.0), older age (HR 1.03) and tumour size >3 cm (HR 1.8) were all independently associated with worse CSS.

CONCLUSION

The WHO1973 classification system for grade has strong prognostic value in T1-BC, compared to the WHO2004 system. Our present results suggest that WHO1973 grade cannot be replaced by the WHO2004 classification in non-muscle-invasive BC guidelines.

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.

Is restaging transurethral resection necessary in patients with non-muscle invasive bladder cancer and limited lamina propria invasion?

OBJECTIVES

To evaluate the influence of lamina propria invasion type at initial transurethral resection (TUR) on restaging pathology.

MATERIALS AND METHODS

We reviewed prospectively maintained records of all patients with a high-grade pT1 nonmuscle invasive bladder cancer who underwent both initial and restaging TUR within 6 weeks at our center between 2001 and 2016. The pathology of second TUR specimens was analyzed with regard to the characteristics of lamina propria invasion found at initial resection.

RESULTS

We included 198 patients, with a median age of 70 years (interquartile range: 63-79). Muscle was present in the initial TUR specimen in 107 patients (54%). Pathology restaging was pT0 in 73 patients (37%), pTis in 44 (22%), pTa in 27 (14%), pT1 in 50 (25%), and pT2 in 4 (2%). Eighty-seven patients (44%) had tumors with minimal lamina propria invasion at initial TUR: 53 specimens (27%) had focal invasion (few malignant cells in the lamina propria); 15 specimens (7.6%) had superficial invasion (invasion of the lamina propria to the level of the muscularis mucosae [T1a]); and 19 specimens (10%) had multifocal superficial invasion (multiple areas of T1a). Of the patients with minimal lamina propria invasion, residual disease was found in 54 patients (62%). However, none of those patients had T2 disease.

CONCLUSIONS

A significant number of patients with T1 tumors have residual disease at restaging TUR as do patients with minimal lamina propria invasion. The extent of T1 invasion does not eliminate the need for repeat TUR.

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.

Easily Available Blood Test Neutrophil-To-Lymphocyte Ratio Predicts Progression in High-Risk Non-Muscle Invasive Bladder Cancer

Introduction: The inflammatory response surrounding the tumour has a major importance in the oncologic outcome of bladder cancers. One marker proved to be useful and accessible is NLR (neutrophil-to-lymphocyte ratio). The objective of the study was the analysis of NLR as a prognostic factor for recurrence and progression in pT1a and pT1b bladder cancers.

Material and Methods: Retrospective study, with 44 T1a/T1b bladder cancer patients. Each patient underwent transurethral resection. NLR was considered altered if higher than 3, average follow-up period was of 18 months.

Results: The mean age of the patients included was 73 years (IQR 64 - 77). Most of the patients had NLR<3 (30 patients). In total 29/44 (65.9 %) patients presented recurrence and 15/44 (34.1 %) patients were identified with T2 or higher stage progression during the follow-up period (average 18 months).We found no statistically significant association between NLR>3 and other clinic and pathologic factors. Progression-free survival (PFS) Kaplan-Meier analysis showed a lower PFS in the NLR>3 group, with a p=0.001 value. A total of 64.3% of patients had shown progression in the NLR>3 group and 20% in the NLR<3 group. Mean NLR was 2.67 (IQR 1.88-3.5); 2.50 (IQR 1.89-2.87) in patients that did not present any progression during the follow-up and 3.20 (IQR 1.73-5.80) in those with progression (p=0.09), ROC 0.655. Mean NLR was 2.14 (IQR 1.61-2.77) in patients that did not experience a recurrence during the follow-up and 2.76 (IQR 2.1-4.31) in those with recurrence, ROC 0.671 (p=0.06). Multivariable Cox regression analyses showed that stage T1b and NLR represent independent prognostic factors for PFS.

Conclusion: High Neutrophil-to-Lymphocyte ratio retained a statistically significant value, as an independent prognostic factor for bad prognosis of T1 bladder tumors. NLR represents a biomarker that could support a clinical decision making in case of high-risk on-muscle invasive bladder cancer.

Predicting Nonmuscle Invasive Bladder Cancer Recurrence and Progression in a United States Population

PURPOSE

We assessed the performance of the EORTC (European Organisation for Research and Treatment of Cancer) and CUETO (Club Urológico Español de Tratamiento Oncológico) nonmuscle invasive bladder cancer predictive models compared to current United States NCCN Guidelines® in an American population.

MATERIALS AND METHODS

We retrospectively analyzed the electronic medical records of patients with nonmuscle invasive bladder cancer in a multicenter population in the United States. We evaluated recurrence-free and progression-free survival according to EORTC and CUETO, and assessed discriminative performance with the c-index at 1 and 5 years. We then compared the discrimination of EORTC and CUETO to the discrimination of the 4 nonmuscle invasive bladder cancer treatment groups described in NCCN Guidelines.

RESULTS

We identified 1,333 patients with nonmuscle invasive bladder cancer and a median followup of 37 months. At 5 years the recurrence c-index of EORTC and CUETO was 0.59 and 0.56 while for progression it was higher at 0.74 and 0.72, respectively. NCCN Guidelines demonstrated a similar c-index of 0.56 and 0.75, respectively. The discrimination of all 3 risk models decreased in patients who received bacillus Calmette-Guérin. EORTC was better able to identify patients at low risk for recurrence or progression but it overestimated the 5-year risk of progression in patients at high risk. This study was limited by its retrospective design.

CONCLUSIONS

Our work illustrates the need for improved predictive tools for clinicians who treat patients with nonmuscle invasive bladder cancer. However, until new tools are developed NCCN Guidelines are a simple option for clinicians who treat patients with nonmuscle invasive bladder cancer. Those guidelines provide predictive power comparable to that of the EORTC and CUETO models.