The role of endoscopic bladder tumour assessment in the management of patients subjected to transurethral bladder tumour resection

Bladder Cancer: Current Challenges and Future Directions

Bladder cancer (BCa) is the most common malignancy of the urinary tract and one of the most prevalent cancers worldwide. While the clinical approach to BCa has remained largely unchanged for many years, recent discoveries have paved the way to a new era of diagnosis and management of the disease. BCa-specific mortality started to decrease in the regions with a wide range of activities leading to greater social awareness of the risk factors and the decline in carcinogenic exposure. The urologic community refines the role of transurethral surgery towards more rigorous and high-quality techniques. New agents have been approved for patients with BCG failure who faced radical cystectomy so far. Although radical removal of the bladder is the gold standard for muscle invasive cancer management, the extent and clinical value of lymphadenectomy is currently heavily challenged in randomized trials. Furthermore, alternatives to perioperative chemotherapy have arisen to increase the likelihood of complete treatment delivery and successful oncological outcomes. Finally, improvements in molecular biology and our understanding of tumorigenesis open the era of personalized medicine in bladder cancer. In the present review, the status and future directions in bladder cancer epidemiology, diagnosis and management are thoroughly discussed.

Consensus Definition and Prediction of Complexity in Transurethral Resection or Bladder Endoscopic Dissection of Bladder Tumours

Simple Summary

Transurethral resection of bladder tumours may be technically challenging. Complexity was defined by consensus from the literature by a panel of ten senior urologists as “any TURBT/En-bloc dissection that results in incomplete resection and/or prolonged surgery (>1 h) and/or significant (Clavien-Dindo ≥ 3) perioperative complications”. Patient and tumour’s characteristics that suggested to by the panel to relate to complex surgery were collected and then ranked by Delphi consensus. They were tested in the prediction of complexity in 150 clinical scenarios. After univariate and logistic regression analyses, significant characteristics were organized into a checklist that predicts complexity. Receiver operating characteristics (ROC) curves of the regression model and the corresponding calibration curve showed adequate discrimination (AUC = 0.916) and good calibration. The resulting Bladder Complexity Checklist can be used to deliver optimal preoperative information and personalise the organisation of surgery.

Abstract

Ten senior urologists were interrogated to develop a predictive model based on factors from which they could anticipate complex transurethral resection of bladder tumours (TURBT). Complexity was defined by consensus. Panel members then used a five-point Likert scale to grade those factors that, in their opinion, drove complexity. Consensual factors were highlighted through two Delphi rounds. Respective contributions to complexity were quantitated by the median values of their scores. Multivariate analysis with complexity as a dependent variable tested their independence in clinical scenarios obtained by random allocation of the factors. The consensus definition of complexity was “any TURBT/En-bloc dissection that results in incomplete resection and/or prolonged surgery (>1 h) and/or significant (Clavien-Dindo ≥ 3) perioperative complications”. Logistic regression highlighted five domains as independent predictors: patient’s history, tumour number, location, and size and access to the bladder. Receiver operating characteristic (ROC) analysis confirmed good discrimination (AUC = 0.92). The sum of the scores of the five domains adjusted to their regression coefficients or Bladder Complexity Score yielded comparable performance (AUC = 0.91, C-statistics, p = 0.94) and good calibration. As a whole, preoperative factors identified by expert judgement were organized to quantitate the risk of a complex TURBT, a crucial requisite to personalise patient information, adapt human and technical resources to individual situations and address TURBT variability in clinical trials.

TGF-β and microRNA Interplay in Genitourinary Cancers

Genitourinary cancers (GCs) include a large group of different types of tumors localizing to the kidney, bladder, prostate, testis, and penis. Despite highly divergent molecular patterns, most GCs share commonly disturbed signaling pathways that involve the activity of TGF-β (transforming growth factor beta). TGF-β is a pleiotropic cytokine that regulates key cancer-related molecular and cellular processes, including proliferation, migration, invasion, apoptosis, and chemoresistance. The understanding of the mechanisms of TGF-β actions in cancer is hindered by the "TGF-β paradox" in which early stages of cancerogenic process are suppressed by TGF-β while advanced stages are stimulated by its activity. A growing body of evidence suggests that these paradoxical TGF-β actions could result from the interplay with microRNAs: Short, non-coding RNAs that regulate gene expression by binding to target transcripts and inducing mRNA degradation or inhibition of translation. Here, we discuss the current knowledge of TGF-β signaling in GCs. Importantly, TGF-β signaling and microRNA-mediated regulation of gene expression often act in complicated feedback circuits that involve other crucial regulators of cancer progression (e.g., androgen receptor). Furthermore, recently published in vitro and in vivo studies clearly indicate that the interplay between microRNAs and the TGF-β signaling pathway offers new potential treatment options for GC patients.