The prognostic value of histological subtype in patients with metastatic bladder cancer

Efficacy of cytoreductive radical cystectomy in metastatic urothelial bladder cancer based on site and number of metastases

BACKGROUND

Recent studies have highlighted the overall survival (OS) benefit of cytoreductive radical cystectomy (CRC) in metastatic bladder cancer (mBCa). Cytoreductive surgery has been established in other urologic cancers. However, the efficacy of CRC and optimal criteria for patient selection in mBCa is unclear. This study investigated the oncologic efficacy of CRC, particularly emphasizing the location and number of metastasis sites as a predictor of survival and treatment response.

METHODS

A retrospective analysis of cT2-4N0-3M1 mBCa patients treated with multiagent chemotherapy between 2004 and 2019 was conducted using the National Cancer Database. Patients were classified by additional treatment with CRC or conservative local treatment (CLT), consisting of transurethral resection of bladder tumor, radiation, or no local treatment and propensity score (PS) matched. Kaplan-Meier analysis and multivariate Cox Proportional Hazards model assessed the effect of CRC or CLT on OS within the matched cohort and in four subgroups (1) patients with only distant lymph node (LN) metastasis vs. any organ metastasis, (2) patients with single metastasis vs. multiple metastases. Sensitivity analysis estimated the influence of unmeasured confounders on CRC OS benefit.

RESULTS

Propensity matching yielded 247 and 251 patients treated with CRC and CLT, respectively. Median OS in patients who received CRC was greater than that of patients treated with CLT (20.4 months vs. 12.0 months, P < 0.001). CRC was associated with reduced mortality risk in patients with only distant LN metastases (HR = 0.545, P = 0.039), any organ metastasis (HR = 0.421, P < 0.001), and single visceral metastasis (HR = 0.483, P = 0.002). However, CRC did not significantly improve OS in patients with multiple metastases (HR = 0.501, P = 0.064).

CONCLUSION

These findings demonstrate an OS benefit of CRC with multiagent chemotherapy and pinpoint multiple visceral metastases as a potential contraindication for CRC. Although limited by the influence of unmeasured confounders, these findings may inform future prospective investigations into CRC.

Urine-derived bladder cancer organoids (urinoids) as a tool for cancer longitudinal response monitoring and therapy adaptation

BACKGROUND

Bladder cancer is one of the most common cancer types worldwide. Generally, research relies on invasive sampling strategies.

METHODS

Here, we generate bladder cancer organoids directly from urine (urinoids). In this project, we establish 12 urinoid lines from 22 patients with non-muscle and muscle-invasive bladder tumours, with an efficiency of 55%.

RESULTS

The histopathological features of the urinoids accurately resemble those of the original bladder tumours. Genetically, there is a high concordance of single nucleotide polymorphisms (92.56%) and insertions & deletions (91.54%) between urinoids and original tumours from patient 4. Furthermore, these urinoids show sensitivity to bladder cancer drugs, similar to their tissue-derived organoid counterparts. Genetic analysis of longitudinally generated tumoroids and urinoids from one patient receiving systemic immunotherapy, identify alterations that may guide the choice for second-line therapy. Successful treatment adaptation was subsequently demonstrated in the urinoid setting.

CONCLUSION

Therefore, urinoids can advance precision medicine in bladder cancer as a non-invasive platform for tumour pathogenesis, longitudinal drug-response monitoring, and therapy adaptation.

Clinicopathologic and Survival After Cystectomy Outcomes in Squamous Cell Carcinoma of the Bladder

BACKGROUND

Squamous cell carcinoma of the bladder (SqCC) is a rare disease with limited management data. Thus, we sought to characterize the clinicopathologic and survival outcomes amongst patients with SqCC and explore the association of squamous differentiation within urothelial carcinoma (UC w/Squam), as compared to muscle invasive pure UC.

METHODS

We conducted a single-center retrospective cohort study of patients, stratified by histology, who underwent cystectomy for MIBC. Baseline clinicopathologic characteristics were compared, and overall survival was assessed using Kaplan-Meier method.

RESULTS

We identified 1,034 patients; 37 (3.58%) with SqCC histology, 908 (87.81%) with UC histology, and 89 (8.61%) with UC w/ Squam histology. Among SqCC patients, a higher proportion were Black and similarly a higher proportion were women; amongst patients with UC w/ Squam a higher proportion had lower BMI; and amongst patients with UC a higher proportion had lower clinical (c) T, cN, pathological (p) T, and pN stages. Patients presenting with UC were more likely to receive intravesical therapy; patients presenting with SqCC were less likely to receive neoadjuvant chemotherapy (NAC). Adjuvant chemotherapy rates were similar. With post-hoc Bonferroni analysis, overall survival, cancer-specific survival, and recurrence-free survival were significantly worse for the UC w/ Squam cohort.

CONCLUSIONS

UC w/ Squam histology was associated with worse survival outcomes after cystectomy for muscle invasive bladder cancer compared to UC. Our results suggest that UC w/ Squam is associated with more advanced disease compared to UC, warranting further prospective work on consideration of combination therapies for patients with this disease state.

The role of smoking in explaining racial/ethnic disparities in bladder cancer incidence in the United States

INTRODUCTION

Smoking is the most important modifiable risk factor for bladder cancer (BC), with the odds of developing BC among current and former smokers 3 times higher than never-smokers. We hypothesized that the observed disparities in BC incidence may be partially attributable to differences in smoking prevalence. We examined the attributable risk of BC related to smoking according to race/ethnicity and sex.

MATERIAL AND METHODS

We used data from SEER and the Behavioral Risk Factor Surveillance System to estimate BC cases that would have been prevented if current and former smokers had never smoked to calculate the Population Attributable Fractions, stratified by sex and race/ethnicity. SDs of BC incidences across racial/ethnic groups before and after smoking elimination were calculated to estimate disparities.

RESULTS

A total of 25,747 cases of BC were analyzed from 21 registries in 2018. By removing smoking, 10,176 cases (40%) would have been eliminated. Smoking was associated with a higher proportion of BC cases among males (42%) than females (36%). Across racial/ethnic groups, smoking contributed to the highest proportion of BC cases among American Indian/Alaska Natives (AI/AN) (43%) and Whites (36%) for females, and highest among AI/ANs (47%) and Blacks (44%) for males. Removing smoking, the SD of BC incidence across racial/ethnic groups was reduced for females (39%) and males (44%).

CONCLUSION

Approximately 40% of cases of BC in the United States are attributable to smoking, with the highest proportion in AI/ANs for both males and females, and the lowest in Hispanics for females and Asians and Pacific Islanders for males. Smoking contributes to almost half of racial/ethnic disparities in BC incidence in the United States. Accordingly, health policy to encourage smoking cessation among racial-ethnic minorities may substantially reduce inequalities in BC incidence.

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.

Web-Based Nomograms for Overall Survival and Cancer-Specific Survival of Bladder Cancer Patients with Bone Metastasis: A Retrospective Cohort Study from SEER Database

BACKGROUND

Our study aimed to explore the prognostic factors of bladder cancer with bone metastasis (BCBM) and develop prediction models to predict the overall survival (OS) and cancer-specific survival (CSS) of BCBM patients.

METHODS

A total of 1438 patients with BCBM were obtained from the SEER database. Patients from 2010 to 2016 were randomly divided into training and validation datasets (7:3), while patients from 2017 were divided for external testing. Nomograms were established using prognostic factors identified through Cox regression analyses and validated internally and externally. The concordance index (C-index), calibration plots, and time-dependent receiver operating characteristic (ROC) curves were used to evaluate the discrimination and calibration of nomogram models, while decision curve analyses (DCA) and Kaplan-Meier (KM) curves were used to estimate the clinical applicability.

RESULTS

Marital status, tumor metastasis (brain, liver, and lung), primary site surgery, and chemotherapy were indicated as independent prognostic factors for OS and CSS. Calibration plots and the overall C-index showed a novel agreement between the observed and predicted outcomes. Nomograms revealed significant advantages in OS and CSS predictions. AUCs for internal and external validation were listed as follows: for OS, 3-month AUCs were 0.853 and 0.849; 6-month AUCs were 0.873 and 0.832; 12-month AUCs were 0.825 and 0.805; for CSS, 3-month AUCs were 0.849 and 0.847; 6-month AUCs were 0.870 and 0.824; 12-month AUCs were 0.815 and 0.797, respectively. DCA curves demonstrated good clinical benefit, and KM curves showed distinct stratification performance.

CONCLUSION

The nomograms as web-based tools were proved to be accurate, efficient, and clinically beneficial, which might help in patient management and clinical decision-making for BCBM patients.

Effects of Different Organ Metastases on the Prognosis of Stage IV Urothelial Carcinoma of the Bladder

Objective

To assess the prognosis of stage IV metastatic urinary bladder urothelial carcinoma (UBUC) at initial diagnosis and determine prognostic factors based on distant organ metastasis.

Methods

A retrospective cohort analysis of UBUC was conducted based on the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression analyses were used to determine the variables associated with overall survival (OS). Kaplan–Meier curves were used to compare survival curves among different groups.

Results

A total of 3103 patients with stage IV UBUC were selected for analysis. The number of distant organ metastatic sites independently predicted the OS. The OS was not different in other metastatic sites when bone metastasis was used as a reference (P > 0.05). However, the OS was shorter for a single metastatic site (P < 0.001) and multiple metastatic sites when metastasis was not used as a reference (P < 0.001). Multivariable Cox regression analysis indicated that low survivorship was independently associated with no surgery for the entire cohort and patients with only one metastatic organ. Sex (P = 0.019) and grade (P = 0.046) were the independent risk factors for patients with only one metastatic organ.

Conclusions

These results show that the prognosis of stage IV metastatic UBUC is not different between any single metastatic organ. The prognosis of stage IV metastatic UBUC depends on the number of distant organ metastasis. This study determined some predictors of survival and thus may help therapists to choose appropriate treatment strategies for metastatic UBUC.

Gender dimorphism in survival of patients with lymph node metastasis of bladder cancer

Background:

The effect of gender on the prognosis of bladder cancer (BCa) in different metastatic sites is insufficiently understood. We aimed to assess the impact and potential mechanisms of a combination of gender dimorphism and BCa metastasis sites on the risk of death.

Methods:

Independent predictors of overall survival and cancer-specific survival were analyzed after stratification by gender and metastasis sites from the Surveillance, Epidemiology, and End Results database. Furthermore, gender-differentially expressed genes (DEGs) and function-enriched annotations for patients with lymph node metastasis (LNM) were identified from The Cancer Genome Atlas (TCGA) database. A gender-associated signature was constructed in TCGA and validated in the IMvigor210 trial, and the magnetic resonance imaging-based radiomics signature was developed in our center to predict the gender-associated signature.

Results:

In patients with metastatic BCa, the most common site of metastasis is bone in men and lung in women. Moreover, stratified by sex, LNM had a better prognosis in men than visceral metastasis, which was not observed in female. Similarly, stratified by the metastasis site, the prognosis of men in patients with LNM is better than that of women, which was not observed in visceral metastasis patients. Enrichment of DEGs between sexes in patients with LNM may be related to metastasis and tumor immunity, especially the role of neutrophils. Moreover, the gender-associated signature is related to the clinicopathological characteristics of patients, and patients in the high-risk group had worse survival outcomes, and higher susceptibility to cisplatin, docetaxel, camptothecin, and paclitaxel. A nomogram combined with the signature and clinical staging showed significant predictive power in survival prediction. Furthermore, patients with high radiomics scores had a strong tendency for high-risk group.

Conclusion:

These results may improve the understanding of the differences in tumor biology between sexes and thus provide additional evidence for individualized treatment in BCa.

Detection of Epithelial-Mesenchymal Transition Markers in High Grade Bladder Cancer and Special Variants of Urothelial Carcinoma

Transitional cell carcinoma is considered the most predominant type of bladder cancer. Bladder can cer can also be found as squamous cell carcinoma that accounts for 5% of the total bladder cancer due to its etiology. The biomarkers associated with grade, prognosis, and stage of the disease are not well proved and known however, many studies have pointed to the association between SNAL/SLUG and Twist2 to the overall survival in patients with bladder cancer. These biomarkers were found to have a crucial role in inhibiting cadherin mediators specifically E-cadherin which are found normally in high level to integrate cell adhesion and normal function of the bladder. This research aims to detect SNAL/SLUG and Twist2 biomarkers in specimens of patients with bladder cancer and to detect their impact on E-cadherin, a tumor suppressor mediator responsible for improving survival and prevent metastasis.

MATERIALS AND METHODS

Using 150 archival tissue blocks from human bladder cancer cases to detect expression of SNAIL/SLUG and Twist2 in relation to loss of E-cadherin by immunohistochemical method.

RESULTS

Our results have revealed that in squamous cell carcinoma 40 specimens showed marked Twist 2 expression, and 30 specimens showed marked snail/slug biomarkers expression while poorly differentiated cancer cases showed marked expression of Twist 2 in 60 specimens and marked expression of Snail/slug marked expression in 50 specimens. Both were associated with E-cadherin loss. Among the 100 specimens with transitional cell carcinoma, 70 specimens showed divergent differentiation with 7 subtypes each showed different medium to high expression of Snail/Slug and Twist 2 biomarkers with the loss of E-cadherin. E-cadherin was strongly associated with the inverse increase in SNAL/SLUG and Twist2 biomarkers in urothelial carcinoma.

CONCLUSION

Detection of SNAIL/SLUG and Twist 2 biomarkers in urothelial cancer is an important predictor for the loss of E-cadherin, a cornerstone in urinary bladder cell adhesion and its loss in urothelial carcinoma may contribute to cancer invasion and poor prognosis. <br />.

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.

Proteomics as a Complementary Technique to Characterize Bladder Cancer

Simple Summary

Although immunohistochemistry is a routine technique in clinics, and genomics has been rapidly incorporated, proteomics is a step behind. This general situation is also the norm in bladder cancer research. This review shows the contributions of proteomics to the molecular classification of bladder cancer, and to the study of histopathology due to tissue insults caused by tumors. Furthermore, the importance of proteomics for understanding the cellular and molecular changes as a consequence of the therapy of bladder cancer cannot be neglected.

Abstract

Bladder cancer (BC) is the most common tumor of the urinary tract and is conventionally classified as either non-muscle invasive or muscle invasive. In addition, histological variants exist, as organized by the WHO-2016 classification. However, innovations in next-generation sequencing have led to molecular classifications of BC. These innovations have also allowed for the tracing of major tumorigenic pathways and, therefore, are positioned as strong supporters of precision medicine. In parallel, immunohistochemistry is still the clinical reference to discriminate histological layers and to stage BC. Key contributions have been made to enlarge the panel of protein immunomarkers. Moreover, the analysis of proteins in liquid biopsy has also provided potential markers. Notwithstanding, their clinical adoption is still low, with very few approved tests. In this context, mass spectrometry-based proteomics has remained a step behind; hence, we aimed to develop them in the community. Herein, the authors introduce the epidemiology and the conventional classifications to review the molecular classification of BC, highlighting the contributions of proteomics. Then, the advances in mass spectrometry techniques focusing on maintaining the integrity of the biological structures are presented, a milestone for the emergence of histoproteomics. Within this field, the review then discusses selected proteins for the comprehension of the pathophysiological mechanisms of BC. Finally, because there is still insufficient knowledge, this review considers proteomics as an important source for the development of BC therapies.

The prognostic effect of metastasis patterns on overall survival in patients with distant metastatic bladder cancer: a SEER population-based analysis

BACKGROUND

The prognostic impact of different distant metastases pattern in bladder cancer is unexplored still now. The aim of this study is to investigate the impact of different distant metastases pattern on the survival of patients with stage IV bladder cancers.

METHODS

A SEER analysis was performed and the overall survival was calculated by the Kaplan-Meier method. Multivariable Cox regression models were used to further analyze survival outcome and other prognostic factors.

RESULTS

A total of 90,382 eligible cases were retrieved in the Surveillance, Epidemiology, and End Results database. Among these patients, stage of IV bladder cancer accounted for 7.03% (6354/90382) at initial diagnosis. Patients who suffered metastasis occupied 35.51% (2256/6354). Comparing with other three single metastases, the patients with liver metastasis exhibited worst OS whose mean of survival was 7.118 months. Multivariate analysis with Cox hazard regression model showed that metastatic site was an independent prognostic factor of OS in patients with single metastasis (P < 0.05). The results of univariate survival analysis showed that metastatic pattern, sex, age, race, tumor stage, N-classification, differentiated grade, histological type, chemotherapy, radiotherapy and insurance status were not significantly correlated with overall survival of patients with two or three metastatic sites (all, P > 0.05).

CONCLUSIONS

Bone was the most common site of single metastasis for bladder cancers. Patients with liver metastasis had worse survival outcome comparing with other three distant metastases. Knowledge of these differences in metastatic patterns might help to better guide pre-treatment evaluation of bladder cancer and make determination regarding curative-intent interventions.

Prognostic nomogram for bladder cancer with brain metastases: a National Cancer Database analysis

Background

This study aimed to establish and validate a nomogram for predicting brain metastasis in patients with bladder cancer (BCa) and assess various treatment modalities using a primary cohort comprising 234 patients with clinicopathologically-confirmed BCa from 2004 to 2015 in the National Cancer Database.

Methods

Machine learning method and Cox model were used for nomogram construction. For BCa patients with brain metastasis, surgery of the primary site, chemotherapy, radiation therapy, palliative care, brain confinement of metastatic sites, and the Charlson/Deyo Score were predictive features identified for building the nomogram.

Results

For the original 169 patients considered in the model, the areas under the receiver operating characteristic curve (AUC) were 0.823 (95% CI 0.758–0.889, P < 0.001) and 0.854 (95% CI 0.785–0.924, P < 0.001) for 0.5- and 1-year overall survival respectively. In the validation cohort, the nomogram displayed similar AUCs of 0.838 (95% CI 0.738–0.937, P < 0.001) and 0.809 (95% CI 0.680–0.939, P < 0.001), respectively. The high and low risk groups had median survivals of 1.91 and 5.09 months for the training cohort and 1.68 and 8.05 months for the validation set, respectively (both P < 0.0001).

Conclusions

Our prognostic nomogram provides a useful tool for overall survival prediction as well as assessing the risk and optimal treatment for BCa patients with brain metastasis.

Prognostic value of site-specific metastases for patients with advanced intrahepatic cholangiocarcinoma: A SEER database analysis

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with poor prognosis and increasing incidence. Due to its asymptomatic manifestation, ICC often progresses to a metastatic stage on diagnosis. The current study attempted to evaluate the prognostic value of site-specific metastases in patients with metastatic ICC.Surveillance, Epidemiology, and End Results (SEER) database (2010-2015) was queried and metastatic ICC patients were classified according to the metastatic sites. Kaplan-Meier analysis was used for survival comparisons and multivariate analysis was performed to elicit characteristics independently associated with survival.A total of 1567 patients were identified and included in the analysis. Compared with those with multiple-site metastases, patients with single-site metastases had better prognostic outcomes. Among the single-site metastases, regional lymph nodes metastases had the best prognosis; liver metastases had better prognostic outcomes than bone metastases; no significant difference was found between lung and bone or liver metastasis. Local treatment of primary tumor might benefit patients with isolated lymph nodes metastases and few exceptional cases of patients with liver metastases.Different metastatic sites have distinct impact on the survival outcomes of patients with advanced ICC and highly selected subset of them might benefit from the local treatment of the primary tumor.

Does Health Insurance Modify the Association Between Race and Cancer-Specific Survival in Patients with Urinary Bladder Malignancy in the U.S.?

Background: Scientific evidence on the effect of health insurance on racial disparities in urinary bladder cancer patients' survival is scant. The objective of our study was to determine whether insurance status modifies the association between race and bladder cancer specific survival during 2007-2015. Methods: The 2015 database of the cancer surveillance program of the National Cancer Institute (n = 39,587) was used. The independent variable was race (White, Black and Asian Pacific Islanders (API)), the main outcome was cancer specific survival. Health insurance was divided into uninsured, any Medicaid and insured. An adjusted model with an interaction term for race and insurance status was computed. Unadjusted and adjusted Cox regression analysis were applied. Results: Health insurance was a statistically significant effect modifier of the association between race and survival. Whereas, API had a lower hazard of death among the patients with Medicaid insurance (HR 0.67; 95% CI 0.48-0.94 compared with White patients, no differences in survival was found between Black and White urinary bladder carcinoma patients (HR 1.24; 95% CI 0.95-1.61). This may be due a lack of power. Among the insured study participants, Blacks were 1.46 times more likely than Whites to die of bladder cancer during the 5-year follow-up (95% CI 1.30-1.64). Conclusions: While race is accepted as a poor prognostic factor in the mortality from bladder cancer, insurance status can help to explain some of the survival differences across races.

Autophagy modulation in bladder cancer development and treatment (Review)

Bladder cancer (BC) is a potentially life-threatening malignancy. Due to a high recurrence rate, frequent surveillance strategies and intravesical drug therapies, BC is considered one of the most expensive tumors to treat. As a fundamental evolutionary catabolic process, autophagy plays an important role in the maintenance of cellular environmental homeostasis by degrading and recycling damaged cytoplasmic components, including macromolecules and organelles. Scientific studies in the last two decades have shown that autophagy acts as a double-edged sword with regard to the treatment of cancer. On one hand, autophagy inhibition is able to increase the sensitivity of cancer cells to treatment, a process known as protective autophagy. On the other hand, autophagy overactivation may lead to cell death, referred to as autophagic cell death, similar to apoptosis. Therefore, it is essential to identify the role of autophagy in cancer cells in order to develop novel therapeutic agents. In addition, autophagy may potentially become a novel therapeutic target in human diseases. In this review, the current knowledge on autophagy modulation in BC development and treatment is summarized.

The clinicopathological characteristics and prognostic value of squamous differentiation in patients with bladder urothelial carcinoma: a meta-analysis

PURPOSE

Urothelial carcinoma with squamous differentiation (UCSD) is the most common histologic variant in bladder cancer (BCa). Previously, some studies have linked the presence of UCSD with the risk of worse survival outcomes in BCa patients. However, such association is still controversial. In this study, we performed a meta-analysis to clarify the clinicopathological characteristics and to further investigate the prognostic value of UCSD in BCa.

METHODS

A systematic literature search was performed in electronic databases including PubMed, Embase, Chinese National Knowledge Infrastructure and Wanfang Data until October 2018. Subgroup analyses were performed according to different treatments and study outcomes.

RESULTS

Total of 13,284 patients were enrolled in 19 studies which were included in this meta-analysis. The percentage of female patients with UCSD was significantly higher than those with pure urothelial carcinoma. UCSD was correlated with tumor stage T3/T4, tumor grade 3, positive surgical margin, and lymph node involvement. Moreover, the recurrence rate was higher in patients with UCSD after surgery. UCSD was associated with poorer disease-free survival (DFS). No significant difference of cancer-specific survival (CSS) or overall survival (OS) was found on multivariable analysis between the two groups.

CONCLUSIONS

Our study demonstrated that UCSD in BCa was associated not only with unfavorable clinicopathological features, but also with high risk of recurrence and poorer prognosis for DFS. However, UCSD is not independently significant for CSS and OS. Well-designed randomized study with larger sample size is warranted to verify the findings and to further explore the role of UCSD in BCa.

Histologic variants associated with biological aggressiveness and poor prognosis in patients treated with radical cystectomy

BACKGROUND

The prognostic value of histologic variants (HV) after radical cystectomy (RC) remains controversial. We evaluated the clinicopathological features and prognosis in patients with pure urothelial carcinoma (UC) and HV following RC.

METHODS

From 1990 to 2015, 286 patients with bladder cancer were treated with RC at six Kitasato University-affiliated hospitals. All patients were divided into two groups: pure UC and HV, which contained pure variants and mixed-type UC with variant pattern. A comparison of patient characteristics between the two groups was made to assess the clinicopathological features, and statistical analyses were performed to investigate prognosis in the two groups.

RESULTS

Of the 286 patients, 226 (79%) had pure UC, while 60 (21%) had HV. Of all HV, pure variants accounted for 45% (n = 27). The prevalence of lymph node involvement, locally advanced stage (≥ pT3), positive soft tissue surgical margin and lymphovascular invasion were significantly higher in patients with HV than in those with pure UC. Patients with HV showed worse disease-free survival and cancer-specific survival than those with pure UC (P = 0.009 and 0.003, respectively). In multivariate analysis, HV and lymph node involvement were independent predictors of worse disease-free survival (P = 0.017 and 0.001, respectively). HV, locally advanced stage, lymph node involvement, and positive soft tissue surgical margin were also confirmed as independent predictors of worse cancer-specific survival (P = 0.011, 0.012, 0.003 and 0.010, respectively.).

CONCLUSIONS

HV was associated with greater biological aggressiveness and worse prognosis than pure UC.

The impact of squamous histology on survival in patients with muscle-invasive bladder cancer

BACKGROUND

Bladder cancer is the ninth most common noncutaneous malignancy worldwide, though a fraction (2%-5%) are diagnosed as squamous cell carcinoma (SCC) in the Western world. Current understanding is based on small, single-institution studies and SEER-database reviews with conflicting results. We used the National Cancer Database to explore clinical characteristics and outcomes from a large cohort of invasive bladder SCC.

METHODS

We queried the National Cancer Database for diagnoses of urothelial carcinoma (UC) or SCC using International Classification of Disease-O-3 morphologic codes from cases reported between 2004 and 2015. Primary outcome was overall survival in cT2-4N0M0 bladder cancer. Statistical analysis performed using chi-squared test, Kaplan-Meier survival, binomial logistic regression, and Cox proportional hazards.

RESULTS

The final cohort included 394,979 bladder cancer patients, of which 4,783 (1.2%) were classified as SCC histology. In comparison to UC, patients with SCC were more likely female (49% vs. 24%; P < 0.01) and African American (11% vs. 5%; P < 0.01). Patients with SCC presented at a higher stage than UC with muscle-invasive bladder cancer (MIBC) present at diagnosis in 70% vs. 19%. On multivariate analysis, SCC independently predicted poorer prognosis (hazard-ratio [HR] 1.79, P < 0.01) when controlling for patient characteristics and treatment modality. Unlike UC, there was no benefit with the use of NAC over radical cystectomy alone (HR 0.93, P = 0.69) for patients with SCC.

CONCLUSIONS

Invasive SCC of the bladder carries a worse prognosis as compared to UC histology, both overall and on a stage-for-stage basis. As opposed to UC, we did not observe a survival benefit for NAC among SCC patients treated with cystectomy.

Comparison of different prognostic models for predicting cancer-specific survival in bladder transitional cell carcinoma

OBJECTIVE

To construct the newly valuable nomogram which can compare the predictive performance with American Joint Committee on Cancer (AJCC) staging system in bladder transitional cell carcinoma (BTCC).

METHODS

BTCC patients were screened (2004-2015) from the SEER database. The nomogram incorporating lymph node ratio was constructed to evaluate individualized cancer-specific survival.

RESULTS

The C-index of the nomogram for predicting cancer-specific survival was 0.743 (95% CI: 0.720-0.766), which was higher than C-index of the AJCC staging system.

CONCLUSION

Lymph node ratio can be a reliable prognostic indicator for BTCC. The proposed nomogram showed more satisfactory predictive accuracy and wider applicability than current AJCC staging system in individualized prediction of BTCC patients.

Racial differences in Urinary Bladder Cancer in the United States

Urinary bladder cancer (UBC) has a high incidence rates in many southern and eastern European countries, in parts of Africa and the Middle East, and in North America. It exhibits a wide variety of histological types that goes from less aggressive to rapid-growing ones. In order to compare the different presentations, etiologies, and prognoses among racial groups, including NHW (non-Hispanic white), HW (Hispanic white), blacks, and API (Asian and Pacific Islander), we analyzed the UBC patients diagnosed between 1973 and 2014 using SEER (Surveillance, Epidemiology, and End Results) database. Patient characteristics, age-adjusted incidence rates, and survival were compared across races. There are significant racial differences in patients' characteristics, including gender, marital status, age at diagnosis, treatment strategies, grade, stage, survival time, and so on. Overall, non-Hispanic whites have the highest incidence rate, followed by blacks, Hispanic whites, and APIs. In the analysis of survival, significant racial differences exist when stratified by gender, age group, histological type, stage, location and treatment strategies. Racial differences exist among UBC patients in the United States in terms of characteristics, incidence, and survival. Future studies may collect and analyze more data for comprehensive description and interpretation of the racial differences.

Prognostic value of site-specific metastases and therapeutic roles of surgery for patients with metastatic bladder cancer: a population-based study

Background

We aimed to evaluate the prognostic value of site-specific metastases in patients with metastatic bladder cancer and analyze the roles that surgeries play in the treatment of this malignancy.

Materials and methods

A population-based retrospective study using Surveillance, Epidemiology and End Results dataset was performed and metastatic bladder cancer patients were classified according to the sites of metastases (bone, brain, liver, lung and distant lymph nodes). Kaplan–Meier analysis with log-rank test was used for survival comparisons. Multivariate Cox regression model was employed to analyze the effect of distant metastatic sites on overall survival (OS) and cancer-specific survival (CSS).

Results

A total of 1862 patients with metastatic bladder cancer from 2010 to 2014 were identified. Bone, lung and distant lymph nodes were the most common metastatic sites. Patients with bone, brain, liver and lung involvement had worse OS and CSS compared to patients without the corresponding sites of metastases. Multivariate analysis showed that bone, brain, liver and lung metastases were independent prognostic factors for both OS and CSS, while distant node metastasis was not. Moreover, patients with a single metastatic site had more favorable OS (p<0.001) and CSS (p<0.001) than patients with multisite metastases. Among single-site metastatic patients, distant nodes and liver metastases represented the best and the worst prognosis, respectively. Moreover, radical cystectomy was an independent predictor for better OS and CSS, while in patients with liver metastasis and multiple metastatic sites, RC did not bring benefits. Besides, in patients with a single metastatic site, metastasectomy seemed to be associated with favorable OS (p=0.042), especially for patients with age <65 years (p=0.006) and for muscle-invasive bladder cancer patients (p=0.031).

Conclusion

Distant metastatic sites have differential impact on survival outcomes in patients with metastatic bladder cancer. Surgeries, including radical cystectomy and metastasectomy, might still lead to survival benefits for highly selected patients.

Bladder cancer stem cells: clonal origin and therapeutic perspectives

In this article, we review the origin and therapeutic perspectives of bladder cancer stem cells (BCSCs), which are integral to the initiation, high recurrence and chemoresistance of bladder cancer. BCSCs are heterogenous and originate from multiple cell types, including urothelial stem cells and differentiated cell types, including basal, intermediate stratum and umbrella cells. Cell surface markers, including CD44, CD67LR, EMA, ALDH1A1 and BCMab1, are used to identify and isolate BCSCs. The Hedgehog, Notch, Wnt and JAK-STAT signaling pathways play key roles in maintaining the stemness, self-renewal and proliferative potential of BCSCs. High expression of ABC transporters, acetaldehyde dehydrogenase, antioxidants and apoptosis resistance proteins in BCSCs play a critical role in chemoresistance. Consequently, a greater understanding of the biology of BCSCs will be important for identifying effective therapeutic targets to improve clinical outcomes for bladder cancer patients.