Effect of Nonurothelial Histologic Variants on the Outcomes of Radical Cystectomy for Nonmetastatic Muscle-invasive Urinary Bladder Cancer

Prognostic impact of histological discordance between transurethral resection and radical cystectomy

OBJECTIVE

To analyse the impact of histological discordance of subtypes (subtypes or divergent differentiation [DD]) in specimens from transurethral resection (TUR) and radical cystectomy (RC) on the outcome of the patients with bladder cancer receiving RC.

PATIENTS AND METHODS

We analysed data for 2570 patients from a Japanese nationwide cohort with bladder cancer treated with RC between January 2013 and December 2019 at 36 institutions. The non-urinary tract recurrence-free survival (NUTR-FS) and overall survival (OS) stratified by TUR or RC specimen histology were determined. We also elucidated the predictive factors for OS in patients with subtype/DD bladder cancer.

RESULTS

At median follow-up of 36.9 months, 835 (32.4%) patients had NUTR, and 691 (26.9%) died. No statistically significant disparities in OS or NUTR-FS were observed when TUR specimens were classified as pure-urothelial carcinoma (UC), subtypes, DD, or non-UC. Among 2449 patients diagnosed with pure-UC or subtype/DD in their TUR specimens, there was discordance between the pathological diagnosis in TUR and RC specimens. Histological subtypes in RC specimens had a significant prognostic impact. When we focused on 345 patients with subtype/DD in TUR specimens, a multivariate Cox regression analysis identified pre-RC neutrophil-lymphocyte ratio and pathological stage as independent prognostic factors for OS (P = 0.016 and P = 0.001, respectively). The presence of sarcomatoid subtype in TUR specimens and lymphovascular invasion in RC specimens had a marginal effect (P = 0.069 and P = 0.056, respectively).

CONCLUSION

This study demonstrated that the presence of subtype/DD in RC specimens but not in TUR specimens indicated a poor prognosis. In patients with subtype/DD in TUR specimens, pre-RC neutrophil-lymphocyte ratio and pathological stage were independent prognostic factors for OS.

Can We Go beyond Pathology? The Prognostic Role of Risk Scoring Tools for Cancer-Specific Survival of Patients with Bladder Cancer Undergoing Radical Cystectomy

Radical cystectomy (RC) remains a mainstay surgical treatment for non-metastatic muscle-invasive and BCG-unresponsive bladder cancer. Various perioperative scoring tools assess comorbidity burden, complication risks, and cancer-specific mortality (CSM) risk. We investigated the prognostic value of these scores in patients who underwent RC between 2015 and 2021. Cox proportional hazards were used in survival analyses. Risk models' accuracy was assessed with the concordance index (C-index) and area under the curve. Among 215 included RC patients, 63 (29.3%) died, including 53 (24.7%) cancer-specific deaths, with a median follow-up of 39 months. The AJCC system, COBRA score, and Charlson comorbidity index (CCI) predicted CSM with low accuracy (C-index: 0.66, 0.65; 0.59, respectively). Multivariable Cox regression identified the AJCC system and CCI > 5 as significant CSM predictors. Additional factors included the extent of lymph node dissection, histology, smoking, presence of concomitant CIS, and neutrophil-to-lymphocyte ratio, and model accuracy was high (C-index: 0.80). The internal validation of the model with bootstrap samples revealed its slight optimism of 0.06. In conclusion, the accuracy of the AJCC staging system in the prediction of CSM is low and can be improved with the inclusion of other pathological data, CCI, smoking history and inflammatory indices.

Adenocarcinoma of the Bladder: Assessment of Survival Advantage Associated With Radical Cystectomy and Comparison With Urothelial Bladder Cancer

PURPOSE

To evaluate the association between radical cystectomy (RC) and cancer-specific mortality (CSM) in patients diagnosed with adenocarcinoma of the bladder (ACB). Moreover, to directly compare the survival advantage of RC between ACB vs. urothelial bladder cancer (UBC).

MATERIALS AND METHODS

Non-metastatic muscle-invasive ACB and UBC patients were identified within Surveillance, Epidemiology, and End Results database (SEER 2000-2018). All analyses were stratified between RC vs. no-RC, in either organ-confined (OC: T2N0M0) or non-organ-confined (NOC: T3-4N0M0 or TanyN1-3M0) stages. Propensity score matching (PSM), cumulative incidence plots, competing risks regression (CRR) analyses, and 3 months' landmark analyses were performed.

RESULTS

Overall, 1,005 ACB and 47,741 UBC patients were identified, of whom 475 (47%) and 19,499 (41%) were treated with RC, respectively. After PSM, comparison between RC vs. no-RC applied to 127 vs. 127 OC-ACB, 7,611 vs. 7,611 OC-UBC, 143 vs. 143 NOC-ACB, and 4,664 vs. 4,664 NOC-UBC patients. 36-month CSM rates in RC vs. no-RC patients were 14 vs. 44% in OC-ACB, 18 vs. 39% in OC-UBC, 49 vs. 66% in NOC-ACB, and 44 vs. 56% in NOC-UBC patients. In CRR analyses, the effect of RC on CSM yielded a hazard ratio of 0.37 in OC-ACB, of 0.45 in OC-UBC, of 0.65 in NOC-ACB and of 0.68 in NOC-UBC patients (all P values<0.001). Landmark analyses virtually perfectly replicated the results.

CONCLUSIONS

In ACB, regardless of stage, RC is associated with lower CSM. The magnitude of this survival advantage was greater in ACB than in UBC, even after control for immortal time bias.

Conditional survival for non-metastatic muscle-invasive adenocarcinoma of the urinary bladder after radical cystectomy

PURPOSE

To test the effect of conditional survival on 36-months' cancer-specific mortality (CSM)-free survival in non-metastatic muscle-invasive adenocarcinoma of the bladder (ACB).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2000-2018), ACB patients treated with radical cystectomy (RC) were identified. Multivariable competing risks regression (CRR) analyses assessed the independent predictor status of organ-confined (OC, T₂N₀M₀) vs non-organ-confined stage (NOC, T_3-4N₀M₀ or T_anyN_1-3M₀) on CSM. Conditional 36-months' CSM-free survival estimates were computed based on event-free intervals of 12, 24, 36, 48 and 60 months after RC, according to stage.

RESULTS

Of 475 ACB patients, 132 (28%) harbored OC vs 343 (72%) harbored NOC stage. In multivariable CRR models, NOC vs OC stage independently predicted lower CSM (hazard ratio 3.55; 95% CI 2.66, 5.83; p < 0.001). Conversely, neither chemotherapy nor radiotherapy were independently associated with CSM. In OC stage, 36-months' CSM-free survival rate was 84% at baseline. Provided event-free intervals of 12, 24, 36, 48 and 60 months, conditional 36-months' CSM-free survival estimates were 84, 87, 87, 89 and 89%. In NOC stage, 36-months' CSM-free survival rate was 47% at baseline. Provided event-free intervals of 12, 24, 36, 48 and 60 months, conditional 36-months' CSM-free survival estimates were 51, 62, 69, 78 and 85%.

CONCLUSIONS

Conditional survival estimates provide better insight into survival of patients with longer event-free follow-up. In consequence, conditional survival estimates might be highly valuable for individual patient counselling.

Comparison of clinicopathological characteristics, gene expression profiles, mutational analysis, and clinical outcomes of pure and mixed small-cell carcinoma of the bladder

AIMS

Small cell bladder carcinoma (SCBC) is a rare, divergent form of urothelial carcinoma (UC). We aimed to determine whether pure (n = 16) and mixed (SCBC and UC; n = 30) tumours differed in pathology, gene expression characteristics, genetic alterations, and clinical outcomes.

METHODS AND RESULTS

Forty (87%) patients received first-line chemotherapy. Twenty-nine patients had no metastatic disease at diagnosis and underwent radical cystectomy. There were no differences in age, sex, race distribution, tumour size, stage at presentation, therapy response with pathological downstaging to ≤ypT1N0, or overall or progression-free survival (PFS) between pure and mixed tumours. There was a longer PFS among downstaged chemotherapy-responding tumours ≤ypT2N0M0 than among unresponsive tumours ≥ypT2 ≥ yN1M1 (P = 0.001). Patients who achieved pathological downstaging with neoadjuvant chemotherapy (n = 10) were stage cT2N0M0 at the time of diagnosis and were alive at the last follow-up (median 37 months), while 46% of patients who failed to achieve pathological downstaging were alive at the last follow-up (median 38 months; P = 0.008). RNA sequencing showed that the UC of mixed SCBC had similar neural expression signatures to pure SCBC. DNA sequencing revealed alterations in TERT (83%), P53 (56%), ARID1A (28%), RB1 (22%), and BRCA2 (11%). Immunohistochemistry for RB1 showed loss of expression in 18/19 (95%) patients, suggesting frequent pathway downregulation despite a low prevalence of RB1 mutation.

CONCLUSION

Patients with pure and mixed SCBC have similar outcomes and these outcomes are determined by the pathological stage at RC and are best among patients who have pathological downstaging after NAC.

Neoadjuvant and Adjuvant Chemotherapy for Variant Histology Bladder Cancers: A Systematic Review and Meta-Analysis

Context

To improve the prognosis of variant histology (VH) bladder cancers, clinicians have used neoadjuvant chemotherapy (NAC) or adjuvant chemotherapy (AC) on the basis of radical cystectomy (RC). Despite some new data, the evidence remains mixed on their efficacy.

Objective

To update the current evidence on the role of NAC and AC for VH bladder cancers.

Evidence Acquisition

We searched for all studies investigating NAC or AC for bladder cancer patients with variant histology in PubMed, Embase, and the Cochrane Central Register of Controlled Trials up to December 2021. The primary end points were recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS).

Evidence Synthesis

We identified 18 reports comprising a total of 10,192 patients in the NAC studies. In patients with VH, the use of NAC did improve CSS (hazard ratio [HR] 0.74, 95% confidence interval [CI] 0.55–0.99, p = 0.044), and OS (HR 0.74, 95% CI 0.66–0.84, p = 0.000), but not RFS (HR 1.15, 95% CI 0.56–2.33, p = 0.706). Subgroup analyses demonstrated that receiving NAC was associated with better OS in sarcomatoid VH (HR 0.67, 95% CI 0.54–0.83, p = 0.000) and neuroendocrine VH (HR 0.54, 95% CI 0.43–0.68, p = 0.000). For AC, we identified eight reports comprising a total of 3254 patients. There was a benefit in CSS (HR 0.61, 95% CI 0.43–0.87, p = 0.006) and OS (HR 0.76, 95% CI 0.60–0.98, p = 0.032). Subgroup analyses demonstrated that only neuroendocrine VH had better CSS (HR 0.29, 95% CI 0.13–0.67, p = 0.174) when receiving AC.

Conclusions

NAC or AC for VH bladder cancers confers an OS and CSS benefit compared with RC alone. For NAC, the benefit was independently observed in the sarcomatoid and neuroendocrine subgroups. As for AC, only neuroendocrine subgroups improved CSS.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021289487.

Clinical and Genomic Characterization of Bladder Carcinomas With Glandular Phenotype

PURPOSE

To compare oncologic outcomes and genomic alteration profiles in patients with bladder and urachal adenocarcinoma, urothelial carcinoma (UC) with glandular differentiation, and UC, not otherwise specified (NOS) undergoing surgical resection, with emphasis on response to systemic therapy.

METHODS

We identified patients with bladder cancer with glandular variants who underwent surgical resection at Memorial Sloan Kettering from 1995 to 2018 (surgical cohort) and/or patients who had tumor sequencing using a targeted next-generation sequencing platform (genomics cohort). Pathologic complete and partial response rates to neoadjuvant chemotherapy (NAC) and recurrence-free and cancer-specific survival were measured. Alteration frequencies between histologic subtypes were compared.

RESULTS

Thirty-seven patients with bladder adenocarcinoma, 46 with urachal adenocarcinoma, 84 with UC with glandular differentiation, and 1,049 with UC, NOS comprised the surgical cohort. Despite more advanced disease in patients with bladder and urachal adenocarcinoma, no significant differences in recurrence or cancer-specific survival by histology were observed after adjusting for stage. In patients with UC with glandular differentiation, NAC resulted in partial (≤ pT1N0) and complete (pT0N0) responses in 28% and 17%, respectively. Bladder and urachal adenocarcinoma genomic profiles resembled colorectal adenocarcinoma with frequent TP53, KRAS, and PIK3CA alterations while the genomic profile of UC with glandular differentiation more closely resembled UC, NOS. Limitations include retrospective nature of analysis and small numbers of nonurothelial histology specimens.

CONCLUSION

The genomic profile of bladder adenocarcinomas resembled colorectal adenocarcinomas, whereas UC with glandular differentiation more closely resembled UC, NOS. Differences in outcomes among patients with glandular bladder cancer variants undergoing surgical resection were largely driven by differences in stage. Cisplatin-based NAC demonstrated activity in UC with glandular differentiation, suggesting NAC should be considered for this histologic variant.

Molecular profile of pure squamous cell carcinoma of the bladder identifies major roles for OSMR and YAP signalling

Pure squamous cell carcinoma (SCC) is the most common pure variant form of bladder cancer, found in 2–5% of cases. It often presents late and is unresponsive to cisplatin‐based chemotherapy. The molecular features of these tumours have not been elucidated in detail. We carried out whole‐exome sequencing (WES), copy number, and transcriptome analysis of bladder SCC. Muscle‐invasive bladder cancer (MIBC) samples with no evidence of squamous differentiation (non‐SD) were used for comparison. To assess commonality of features with urothelial carcinoma with SD, we examined data from SD samples in The Cancer Genome Atlas (TCGA) study of MIBC. TP53 was the most commonly mutated gene in SCC (64%) followed by FAT1 (45%). Copy number analysis revealed complex changes in SCC, many differing from those in samples with SD. Gain of 5p and 7p was the most common feature, and focal regions on 5p included OSMR and RICTOR. In addition to 9p deletions, we found some samples with focal gain of 9p24 containing CD274 (PD‐L1). Loss of 4q35 containing FAT1 was found in many samples such that all but one sample analysed by WES had FAT1 mutation or deletion. Expression features included upregulation of oncostatin M receptor (OSMR), metalloproteinases, metallothioneins, keratinisation genes, extracellular matrix components, inflammatory response genes, stem cell markers, and immune response modulators. Exploration of differentially expressed transcription factors identified BNC1 and TFAP2A, a gene repressed by PPARG, as the most upregulated factors. Known urothelial differentiation factors were downregulated along with 72 Kruppel‐associated (KRAB) domain‐containing zinc finger family protein (KZFP) genes. Novel therapies are urgently needed for these tumours. In addition to upregulated expression of EGFR, which has been suggested as a therapeutic target in basal/squamous bladder cancer, we identified expression signatures that indicate upregulated OSMR and YAP/TAZ signalling. Preclinical evaluation of the effects of inhibition of these pathways alone or in combination is merited.

Effect of bladder cancer variant histology on survival outcome in patients treated with radical cystectomy: A single-centre experience

Context

Bladder cancer (BC) is the sixth most common malignant neoplasm in men. Recently, great effort has been devoted to the study of BC variant histology (VH). Yet, the results from these studies have shown conflicting data and remain unclear whether their presence alters recurrence and survival rates after radical cystectomy (RC).

Aims

We undertook this study aiming to test the effect on VH on recurrence-free survival (RFS) and overall survival (OS) in single-center RC patients.

Settings and Design

We have retrospectively analyzed medical records and pathology reports from 331 patients who underwent RC with or without pelvic lymphadenectomy at University Urology Clinic-Skopje, North Macedonia, in the period between 2010 and 2018.

Subjects and Methods

Microscopic analysis of the specimens involved the evaluation of histological tumor type, tumor grade, pathological tumor node metastasis stage, presence of lymphovascular invasion, and resection margin status.

Statistical Analysis Used

Univariable and multivariable Cox regression models were applied to test the effect of VH on RFS and OS.

Results

We found 185 patients who matched our inclusion criteria. At multivariable analyses, lymphovascular invasion and positive resection margins were associated with shorter RFS. Similarly, patients diagnosed with lymphovascular invasion, positive resection margins, and a pelvic lymph node metastasis had poorer OS. VH was not found to be an independent predictor of both RFS and OS (P > 0.05).

Conclusions

The present study did not reveal prognostic effect of VH on RFS and OS. In our series, histomorphologic parameters including lymphovascular invasion, resection margins, and pelvic lymph node metastasis were the most relevant predictors on survival outcome after RC.

Current Knowledge on Genomic Profiling of Upper Tract Urothelial Carcinoma

Recent research in next-generation sequencing characterized the genomic landscape of urothelial cancer. However, the majority of the studies focused on bladder cancer (BC). Upper urinary tract urothelial carcinomas (UTUC) and BC share some histological characteristics, but, considering the differences in terms of embryologic precursors, epidemiology, genetics, medical and surgical management and response to therapy, UTUC and BC should be considered as two distinct diseases. Our objective is to analyze through a literature search the latest updates and the current knowledge about the genomics of UTUC. We also evaluate genetic differences between BC and UTUC and the potential implications for systemic therapy. Molecular subtyping and variant histology and their correlation with response to chemotherapy were also explored. In summary, the most frequent genomic variations in UTUC included FGFR3, chromatin remodeling genes, TP53/MDM2 and other tumor suppressors/oncogenes. The genomics of UTUC, integrated with clinical data, could drive the selection of patients who could benefit from targeted therapy or off-label treatment. Routine implementation of tumor genomic characterization in UTUC patients should therefore be contemplated and evaluated prospectively.

The Effect of Systemic Chemotherapy on Survival in Patients With Localized, Regional, or Metastatic Adenocarcinoma of the Urinary Bladder

OBJECTIVES

To test the effect of systemic chemotherapy on cancer-specific mortality (CSM) in patients with adenocarcinoma of the urinary bladder (ADKUB).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results registry (2004 to 2016), we identified patients with localized (T2-3N0M0), regional (T4N0M0/TanyN1-3M0), and metastatic (TanyNanyM1) ADKUB. Temporal trends, Kaplan-Meier plots, and multivariable Cox regression models were used before and after 1:1 propensity score matching and inverse probability of treatment weighting.

RESULTS

Of 1537 patients with ADKUB, 834 (54.0%), 363 (23.5%), and 340 (22.5%) harbored localized, regional, and metastatic disease, respectively. The rates of chemotherapy use increased in localized (estimated annual percentage change [EAPC]: +2.7%; P=0.03) and regional ADKUB (EAPC: +2.4%; P=0.04). Conversely, chemotherapy rates remained stable in metastatic patients (EAPC: +1.6%; P=0.4). In multivariable Cox regression models, chemotherapy use was associated with lower CSM in metastatic ADKUB (hazard ratio [HR]: 0.5; P=0.003), but not in either localized (HR: 0.8; P=0.2) or in regional ADKUB (HR: 1.0; P=0.9). In metastatic ADKUB, the benefit of chemotherapy on CSM persisted after 1:1 propensity score matching (HR: 0.6; P=0.002) and after inverse probability of treatment weighting (HR: 0.4; P<0.001).

CONCLUSIONS

Chemotherapy improves survival in metastatic ADKUB. However, only one out of 2 such patients benefit from chemotherapy. In consequence, greater emphasis on chemotherapy use may be warranted in these patients. Conversely, no benefit was identified in localized or regional ADKUB.

Nomogram for predicting overall survival of patients with bladder cancer: A population-based study

OBJECTIVE

The aim of this study was to develop and validate a reliable nomogram to estimate overall survival in bladder cancer.

METHOD

Patients diagnosed with bladder cancer identified in the Surveillance, Epidemiology, and End Results database were randomly divided into training and validation cohorts. The powerful prognostic variables were examined using Cox regression analyses. A nomogram was developed on the prognostic factors.

RESULTS

The results suggested that age, sex, race, grade, histologic type, primary site, pathological stage, surgical treatment, and number of primary tumors, were the powerful prognostic factors. All these factors were integrated to construct the nomogram. The nomogram for predicting overall survival showed better discrimination power than the tumor-node-metastasis (TNM) stage system 8th edition.

CONCLUSION

The nomogram has the potential to provide an individualized prediction of overall survival in patients with bladder cancer.

Neuroendocrine Carcinoma of the Urinary Bladder: A Large, Retrospective Study From the French Genito-Urinary Tumor Group

BACKGROUND

Neuroendocrine carcinoma of the urinary bladder (NCUB) is rare, accounting for < 1% of bladder cancer cases, with scarce reported data available.

MATERIALS AND METHODS

We retrospectively reviewed the data from patients with NCUB treated at French institutions. The objectives were to describe the patient characteristics, treatments received, and outcomes (ie, disease-free survival [DFS], progression-free survival, overall survival [OS]) and investigate the prognostic factors.

RESULTS

From 1997 to 2017, we included 236 patients, 173 with early-stage NCUB and 63 with advanced-stage NCUB. For those with early-stage disease, the median DFS was better for the patients who had received cisplatin-based chemotherapy compared with carboplatin (hazard ratio [HR], 1.95; 95% confidence interval [CI], 1.1-3.46), with no difference found between the neoadjuvant and adjuvant settings (HR, 1.1; 95% CI, 0.61-1.97). The median OS was 36 months (95% CI, 29-43 months) for stage I and II, 26 months (95% CI, 18 months to not reached) for stage IIIA, 16 months (95% CI, 12-21 months) for stage IIIB. The HR for stage IIIB compared with stage I/II was 2.6 (95% CI, 1.5-4.4). The DFS at 6 months was associated with OS (HR, 7.8; 95% CI, 4.1-15.0). For patients with metastases at diagnosis who had received chemotherapy, the median progression-free survival was 9 months (95% CI, 8-11) for first-line cisplatin and 6 months (95% CI, 4-13 months) for carboplatin; the median OS was 13 months (95% CI, 9-15 months). A high-risk Bajorin score (HR, 11.5; 95% CI, 1.2-112.6) and the use of carboplatin (HR, 2.26; 95% CI, 1.03-4.96) were associated with worse outcomes.

CONCLUSIONS

In early-stage disease, a shorter DFS was associated with worse OS, and the use of cisplatin was associated with better OS. For the patients with metastases at diagnosis, a high-risk Bajorin score and the use of carboplatin were associated with worse outcomes.

Trends in the use of neoadjuvant chemotherapy for bladder cancer with nonurothelial variant histology: An analysis of the National Cancer Database

Introduction

The aim of this study is to evaluate the trends in the use of neoadjuvant chemotherapy (NAC) over time (2006-2014) for patients diagnosed with muscle-invasive bladder cancer (MIBC) with nonurothelial variant histology (NUVH) in the National Cancer Database.

Materials and Methods

We queried the NCDB for patients with muscle-invasive (i.e. cT2-4N0-3M0/X) urothelial carcinoma (UC) of the bladder. We examined demographic, clinical, and pathologic features associated with NAC, also substratifying into pure UC and NUVH. Tests of association were performed using Chi-square/Fisher's exact test for categorical variables and t-tests, ANOVA, or Kruskal-Wallis test for continuous variables. Outcomes were examined with Cox proportional hazards and 90-day mortality with the Kaplan-Meier method.

Results

Totally 22,320 patients met our inclusion criteria, of whom 22.6% received NAC. The proportion of NAC increased significantly over time in the neuroendocrine and urothelial cell categories with 57.1% and 34.1% of patients in 2014 receiving NAC vs. 44% and 10.6% in 2006. No other variant histology showed a significant increase across the time sampled. Patients receiving NAC were more likely to have downstaging to pT0 (13.4% vs. 2.7%), negative surgical margin (89.1% vs. 86%), and pN0 (63.2% vs. 60.5%) and were less likely to have 30-day (1.4% vs. 3%) or 90-day (5% vs. 8.3%) mortality. Rates of downstaging to pT0 after NAC were similar among histologies.

Conclusion

Neoadjuvant chemotherapy utilization continues to slowly increase in patients with MIBC. Patients with variant histology lag behind in terms of receiving NAC but appear to derive as much benefit as patients with pure urothelial cell bladder cancer.

Survival After Partial Cystectomy for Variant Histology Bladder Cancer Compared With Urothelial Carcinoma: A Population-based Study

BACKGROUND

The present study tested cancer-specific (CSM) and overall mortality (OM) after partial cystectomy (PC) for variant histology bladder cancer (non-urothelial carcinoma of the urinary bladder UCUB), relative to UCUB and relative to radical cystectomy (RC).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results registry (2001-2016), we identified patients with stage T1-T2N0M0 non-UCUB and UCUB who had undergone PC or RC. Non-UCUB included adenocarcinoma, squamous carcinoma, neuroendocrine carcinoma, and other histologic subtypes. First, CSM and OM after PC were compared between the non-UCUB and UCUB groups. Second, CSM and OM after PC were compared with RC in the non-UCUB group. Kaplan Meier plots and multivariable Cox regression models were used before and after inverse probability of treatment weighting.

RESULTS

Overall, 248 patients (16.3%) treated with PC had had non-UCUB. Of the 248 cases, 115 (46.5%), 50 (20%), 34 (14%), and 49 (19.5%) were adenocarcinoma, squamous carcinoma, neuroendocrine carcinoma, and other histologic subtypes, respectively. The comparison between PC in the non-UCUB and PC in the UCUB group showed higher CSM (hazard ratio, 1.4; P = .03) but the same OM rates (hazard ratio, 1.1; P = .7) in the non-UCUB group. The comparison between PC and RC for the non-UCUB group showed no CSM or OM differences.

CONCLUSIONS

PC for non-UCUB was associated with higher CSM compared with PC for UCUB. However, PC instead of RC for select patients with non-UCUB appears not to undermine cancer-control outcomes. Thus, the excess CSM is probably unrelated to cystectomy type but could originate from differences in the tumor biology. These results could act as hypothesis generating for the design of future trials.

Invasive non-urachal adenocarcinoma of the bladder: analysis of the National Cancer Database

PURPOSE

To review the United States National Cancer Database (NCDB) from 2004 to 2015 and analyze survival outcomes of invasive non-urachal adenocarcinoma based on treatment modality.

METHODS

The NCDB 2004-2015 bladder dataset was queried for adenocarcinoma histology, excluding urachal variant, and limited to patients with clinical stage T2-T4 disease. Treatment modality was categorized as no treatment, cystectomy (partial or radical), external beam radiation therapy (EBRT), or EBRT plus cystectomy. Our primary outcome was overall survival. Cox regression (CR) and Kaplan-Meier (KM) analysis were performed.

RESULTS

851 patients were identified with invasive (cT2-T4) adenocarcinoma of the bladder. Treatment modalities included 398 (47.8%) no treatment, 298 (35.8%) cystectomy, 124 (14.9%) EBRT, and 31 (3.7%) EBRT plus cystectomy. On KM analysis excluding those with metastatic disease, the 5-year survival was significantly better (p < 0.001) for patients who underwent cystectomy (39.6%), versus no treatment (21.0%), EBRT (18.6%), or EBRT plus cystectomy (26.9%) (log rank, p < 0.001). On CR for mortality, age (HR 1.030, p < 0.001), Charlson score 1 (HR 1.287, p = 0.034), cT4 (HR 1.768, p < 0.001), and receiving treatment at a low-volume center (HR 1.289, p = 0.026) were associated with worsened survival; however, cystectomy (HR 0.593, p < 0.001) was the only factor associated with improved survival. For those undergoing cystectomy, the mean length of stay was 8.5 days and the 30-day readmission rate was 7.0%.

CONCLUSIONS

Invasive non-urachal adenocarcinoma of the bladder is a rare diagnosis. Survival benefits in patients without metastatic disease are seen only in those patients undergoing definitive surgery.