Bladder Sparing Approaches for Muscle-Invasive Bladder Cancers

Adjuvant Radiotherapy for Upper Tract Urothelial Carcinoma: Systematic Review and Meta-Analysis

PURPOSE

Upper tract urothelial carcinoma (UTUC) is a rare form of malignancy comprising only 5% of urothelial cancers. The mainstay of treatment is radical nephroureterectomy (RNU) with bladder cuff excision. Neoadjuvant or adjuvant chemotherapy is often used in locally advanced disease. The role of adjuvant radiotherapy (RT), however, remains controversial. To further explore the potential role of adjuvant RT, we performed a systematic review and meta-analysis of the literature from 1990 to present.

METHODS AND MATERIALS

We identified 810 candidate articles from database searches, of which 67 studies underwent full-text review, with final inclusion of 20 eligible studies. Among the included studies, there were no randomized controlled trials and a single prospective trial, with the remainder being retrospective series. We performed quantitative synthesis of the results by calculating the pooled odds ratios (OR) for the primary outcome of locoregional recurrence (LRR) and secondary outcomes of overall survival (OS), cancer-specific survival (CSS) and distant recurrence (DR).

RESULTS

Adjuvant RT, which was mostly prescribed for locally advanced or margin-positive disease following RNU, significantly reduced locoregional recurrence risk OR 0.43 (95% CI: 0.23-0.70), and the effect remained significant even following subgroup analysis to account for adjuvant systemic therapy. The effect of adjuvant RT on 3-year OS, 5-year CSS and DR was non-significant. However, 5-year OS was unfavourable in the adjuvant RT arm, but study heterogeneity was high, and analysis of small-study effects and subgroups suggested bias in reporting of outcomes.

CONCLUSIONS

Adjuvant RT in the setting of locally advanced UTUC improves locoregional control following definitive surgery, but does not appear to improve OS. Higher-quality studies, ideally randomized controlled trials, are needed to further quantify its benefit in this setting, and to explore multi-modal treatments that include systemic agents given concomitantly or sequentially with RT, which may offer an OS benefit in addition to the locoregional control benefit of RT.

A review of the biology and therapeutic implications of cancer-associated fibroblasts (CAFs) in muscle-invasive bladder cancer

Cancer-associated fibroblasts (CAFs) play a fundamental role in the development of cancers and their response to therapy. In recent years, CAFs have returned to the spotlight as researchers work to unpick the mechanisms by which they impact tumour evolution and therapy responses. However, study of CAFs has largely been restricted to a select number of common cancers, whereas research into CAF biology in bladder cancer has been relatively neglected. In this review, we explore the basics of CAF biology including the numerous potential cellular origins of CAFs, alongside mechanisms of CAF activation and their diverse functionality. We find CAFs play an important role in the progression of bladder cancer with significant implications on tumour cell signaling, epithelial to mesenchymal transition and the capacity to modify components of the immune system. In addition, we highlight some of the landmark papers describing CAF heterogeneity and find trends in the literature to suggest that the iCAF and myCAF subtypes defined in bladder cancer share common characteristics with CAF subtypes described in other settings such as breast and pancreatic cancer. Moreover, based on findings in other common cancers we identify key therapeutic challenges associated with CAFs, such as the lack of specific CAF markers, the paucity of research into bladder-specific CAFs and their relationship with therapies such as radiotherapy. Of relevance, we describe a variety of strategies used to target CAFs in several common cancers, paying particular attention to TGFβ signaling as a prominent regulator of CAF activation. In doing so, we find parallels with bladder cancer that suggest CAF targeting may advance therapeutic options in this setting and improve the current poor survival outcomes in bladder cancer which sadly remain largely unchanged over recent decades.

Down-regulation of autophagy-associated protein increased acquired radio-resistance bladder cancer cells sensitivity to taxol

BACKGROUND

As a bladder-preserving therapy, radiation therapy (RT) has been widely used in the treatment of bladder cancer (BCa) and made great progress in the past few decades. However, some BCa patients have low RT responsiveness and local recurrence rate after RT could reach 50%. Acquired radio-resistance (ARR) is one of the important reasons for the failure of RT. Unfortunately, these ARR cells also lack sensitivity to chemotherapy and cause tumor recurrence and metastasis.

PURPOSE

To build ARR-phenotype BCa cell model, discuss the possible molecular mechanism of ARR and find effective target molecules to overcome ARR.

MATERIALS AND METHODS

Five thousand six hundred and thirty-seven cells were subjected 30 times to 2 Gy of γ-rays and the surviving cells were called 5637R. Colony formation and MTT assay were applied to evaluate cells sensitivity to ionizing radiation (IR) and anti-neoplastic agents, respectively. Cells abilities of migration and invasion were determined using transwell method. Quantitative real-time polymerase chain reaction (RT-qPCR) and western blot (WB) were respectively utilized to compare the difference of gene and protein expression between 5637 and 5637R cells. Molecule inhibitors and small interfering RNA (siRNA) systems were employed to decrease the expression of target proteins, respectively.

RESULTS

BCa cells survived from fractionated irradiation (FI) exhibited tolerance to both IR and chemotherapy drugs. These ARR cells (5637R) had elevated migration and invasion abilities, accompanied by increased expression of epithelial mesenchymal transition (EMT)-related transcription factors (ZEB1/Snail/Twist). Moreover, 5637R cells showed enhanced cancer stem cell (CSC)-like characteristics with activated KMT1A-GATA3-STAT3 circuit, a newly reported self-renewal pathway of human bladder cancer stem cell (BCSC). Combined with Kaplan-Meier's analysis, we speculated that GATA3/MMP9/STAT3 could be an effective molecular panel predicting poor prognosis of BCa. In order to enhance the sensitivity of resistant cells to radiation, we introduced ERK inhibitor (FR 180204) and STAT3 inhibitor (S3I-201). However, both of them could not enhance ARR cells response to IR. On the other hand, siRNAs were respectively implemented to inhibit the expression of endogenous Beclin1 and Atg5, two important autophagy-related genes, in BCa cells, which significantly increased 5637R cells death upon taxol exposing. Similarly, chloroquine (CQ), a classic autophagy inhibitor, enhanced the cytotoxicity of taxol only on 5637R cells.

CONCLUSIONS

Long-term FI treatment is an effective method to establish the ARR-phenotype BCa cell model, by enriching BCSCs and enhancing cells migration and invasion. Both inhibiting the expression of autophagy-related proteins and using autophagy inhibitor can increase the sensitivity of ARR cells to taxol, suggesting that autophagy may play an important role in ARR cells chemical tolerance.

Review of Experimental Studies to Improve Radiotherapy Response in Bladder Cancer: Comments and Perspectives

Bladder cancer is among the top ten most common cancer types in the world. Around 25% of all cases are muscle-invasive bladder cancer, for which the gold standard treatment in the absence of metastasis is the cystectomy. In recent years, trimodality treatment associating maximal transurethral resection and radiotherapy combined with concurrent chemotherapy is increasingly used as an organ-preserving alternative. However, the use of this treatment is still limited by the lack of biomarkers predicting tumour response and by a lack of targeted radiosensitising drugs that can improve the therapeutic index, especially by limiting side effects such as bladder fibrosis. In order to improve the bladder-preserving treatment, experimental studies addressing these main issues ought to be considered (both in vitro and in vivo studies). Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews, we conducted a literature search in PubMed on experimental studies investigating how to improve bladder cancer radiotherapy with different radiosensitising agents using a comprehensive search string. We made comments on experimental model selection, experimental design and results, formulating the gaps of knowledge still existing: such as the lack of reliable predictive biomarkers of tumour response to chemoradiation according to the molecular tumour subtype and lack of efficient radiosensitising agents specifically targeting bladder tumour cells. We provided guidance to improve forthcoming studies, such as taking into account molecular characteristics of the preclinical models and highlighted the value of using patient-derived xenografts as well as syngeneic models. Finally, this review could be a useful tool to set up new radiation-based combined treatments with an improved therapeutic index that is needed for bladder preservation.

Outcomes of trimodality bladder-sparing therapy for muscle-invasive bladder cancer

INTRODUCTION

Although radical cystectomy is considered the standard of care for muscle-invasive bladder cancer (MIBC), recent data has suggested comparable survival outcomes for bladder-sparing trimodality therapy (TMT). We conducted a retrospective, single-institution analysis of MIBC patients to evaluate the efficacy of TMT as an alternative, curative approach to surgical intervention.

METHODS

We conducted a retrospective analysis of MIBC patients assessed by a multidisciplinary team at the Juravinski Cancer Centre from 2010-2016. Patients underwent transurethral resection of bladder tumor (TURBT) followed by radiotherapy with or without concurrent chemotherapy. Patients could receive neoadjuvant treatment. Clinical data and response rates were summarized, and overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method.

RESULTS

Our analytic cohort included 115 patients, of whom 53 underwent TMT and 62 underwent radiotherapy alone following TURBT. Median age at diagnosis was 79 years and median followup was 21 months. Complete response rates in those receiving TMT and radiation without chemotherapy were 84.4% and 66.7%, respectively. For TMT patients, three-year OS and DFS were 68.5% and 49.6%, respectively. Patients who received TMT had reduction in risk of mortality (hazard ratio [HR] 0.49; p=0.026) and disease recurrence (HR 0.55; p=0.017) compared to those who had radiation without chemotherapy. Overall, four patients had grade 3 or higher late toxicity.

CONCLUSIONS

In this single-institution analysis, TMT appears to be a safe and effective approach in the short-term management of MIBC in appropriately selected patients. Extended followup and analysis are necessary to validate these results.

Elderly patients undergoing cystectomy, comparing preoperative American Society of Anesthesiology and Eastern Cooperative Oncology Group scores and operative approaches

Objective:

To evaluate preoperative scoring systems and operative management and their relation to complications in patients older than 75 years undergoing cystectomy at two academic institutions.

Methods:

In total, 212 patients aged 75–95 years with muscle invasive bladder cancer underwent cystectomy at the University of Utah and Central Hospital of Bolzano, Italy. The rates of Grade 3 Clavien-Dindo complications and above in radical cystectomy patients (n = 199) were compared using Eastern Cooperative Oncology Group Scores and American Society of Anesthesiologists Physical Status Classification. The rates of Grade 3 Clavien-Dindo complications and above were also compared by urinary diversion type. Logistic regression was used to control for source institution.

Results:

In total, 199 cases were included in the primary analysis. Neither of the preoperative scoring systems were predictive for identification of radical cystectomy patients with ⩾Grade 3 Clavien-Dindo complications. In secondary analysis (n = 212, including partial cystectomy), none of the urinary diversion types associated with radical cystectomy had a significantly different rate of complications. However, partial cystectomy (n = 13) had a significantly lower rate of complications.

Conclusion:

Complication rates among elderly patients undergoing cystectomy for muscle invasive bladder cancer were very high. For patients who are approved for surgery after the history and physical exam, none of our objective metrics adequately predicted operative risk. A unique diversion procedure described by the Bolzano group, uretero-ureterocutaneostomy, had equivalent complication rates to the more common diversion procedures. It also appears based on outcomes in this cohort that partial cystectomy is a particularly favorable option within the elderly population in terms of perioperative morbidity.

Perioperative chemotherapy for urothelial carcinoma of the upper urinary tract: A systematic review and meta-analysis

INTRODUCTION

Upper tract urothelial carcinomas are rare malignancies with differences in anatomy and biology requiring therapeutic strategies that differ from bladder cancer. The role of perioperative systemic therapy in this disease remains uncertain with limited data to support its use. A systematic review of the literature and meta-analysis was therefore undertaken to provide more information and guide clinical practice.

METHODS

A literature search was performed using Embase and Medline databases with additional searches performed manually using terms associated with upper tract urothelial malignancies. Data was extracted from studies of patients that underwent nephrouretectomy for the management of upper tract urothelial carcinoma and received either neoadjuvant or adjuvant systemic therapy. Overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were summated and analyzed using Cochrane Revman software Version 5.3.

RESULTS

There were 13 comparative studies and no randomized studies identified for data extraction; 11 adjuvant and 2 neoadjuvant with 1170 patients receiving perioperative systemic therapy and 3472 controls that did not. Perioperative chemotherapy was associated with improved OS (HR 0.75, 95%CI 0.57-0.99), DFS (HR 0.54, 95%CI 0.32-0.92), and CSS (HR 0.69, 95%CI 0.42-1.15).

CONCLUSIONS

The available data suggests that perioperative systemic therapy is associated with improved survival in patients with upper tract urothelial cancer.

Health Related Quality of life in bladder cancer. Current approach and future perspectives

Bladder cancer is a real health problem due to its increased incidence, high recurrence rate and the fact that usually it is detected in advanced stages with limited number of diagnostic tools and different therapy response rates to current therapeutic strategies. Because of these issues we must develop screening programs and sensitive diagnostic strategies capable of detecting the disease during its early stages but also for characterizing evolution, prognosis and therapeutic response. Issues of great importance are those related to health quality of life of patients from the moment of diagnosis till the use of existing therapeutic approaches. This paper reviews some facets of life quality in patients diagnosed with bladder cancer stressing upon some proposed questionnaires and some new cell and molecular biology and genomic acquisitions (molecular biomarkers) that may become indicators of prognosis, therapeutic response and life quality but also essential tools in guiding therapeutic strategies.