Canadian Urological Association guideline on the management of non-muscle-invasive bladder cancer - Abridged version

Optimal interval timing between transurethral resection of bladder tumors and Bacillus Calmette-Guerin perfusion

OBJECTIVE

There is no consensus regarding the best interval time between transurethral resection of a bladder tumor and Bacillus Calmette-Guerin (BCG) perfusion. This study was to explore whether the interval time has an impact on the prognosis and adverse effects.

METHODS

We retrospectively reviewed the clinical data of patients who received BCG intravesical perfusion at Sun Yat-sen University Cancer Center (SYSUCC) from September 2015 to October 2021. Recurrence-free survival (RFS) and progression-free survival were the primary endpoints. Cox regression was used to explore independent predictors. The association between interval time and adverse effect grade was detected by logistic regression. Propensity score matching (PSM) was performed.

RESULTS

A total of 403 patients were enrolled, the median interval time was 24 days (6-163 days), and the follow-up was 28 months (7-82 months). Eighty-eight (20.9%) patients relapsed, and 40 patients (10.0%) suffered progression. The multivariate Cox regression analysis confirmed that interval time was an independent predictor of RFS (p = 0.017). Notably, when the interval time was less than or equal to 26 days, there was a trend toward better RFS, PSM resulted in 65 matched pairs in each group, and Kaplan-Meier analysis showed that there was a significant difference in RFS between groups (p = 0.009). The logistic regression analysis showed that there was no correlation between interval time and adverse effects and their grades (p > 0.05).

CONCLUSIONS

We considered that the first BCG perfusion could be performed within 2-4 weeks after surgery.

Single-Dose Post-Office Fulguration Mitomycin C Instillation Appears to Improve Recurrence-Free Survival in Patients With Low-Grade Noninvasive Bladder Cancer

INTRODUCTION

Perioperative instillation of mitomycin-C (MMC) has shown effectiveness in reducing the recurrence of low-grade non-muscle invasive bladder cancer (NMIBC). Data is lacking about the impact of single-dose MMC following office fulguration of low-grade urothelial carcinoma. We compared the outcomes of small-volume low-grade recurrent NMIBC in patients treated with office-fulguration - with and without an immediate single-dose instillation of MMC.

PATIENTS AND METHODS

A retrospective analysis of medical records of patients with recurrent small-volume (≤1 cm) low-grade papillary urothelial cancer who underwent fulguration in a single institution between January 2017 and April 2021 either with or without instillation of post-fulguration MMC (40mg/50 mL). The primary outcome was recurrence-free survival (RFS).

RESULTS

Of 108 patients (27% women) who underwent fulguration, 41% received intravesical MMC. The treatment and control groups had similar sex ratio, mean age, mass size, tumor multifocality and or tumor grade. Median RFS was 20 months (95% CI 4-36) in the MMC group and 9 months (95% CI 5-13) in the control group (P = .038). Multivariate Cox regression analysis showed that MMC instillation was associated with longer RFS (OR = 0.552, 95% CI 0.320-0.955, P = .034) and multifocality was associated with shorter RFS (OR = 1.866, 1.078-3.229, P = .026). A higher rate of grade 1-2 adverse events was observed in the MMC group (18.2%) vs. the control (6.8%, P = .048). No complications grade 3 or higher were observed.

CONCLUSION

A single dose of MMC instilled after office fulguration is associated with longer RFS compared to patients who did not receive MMC after the procedure, with no associated high-grade complications.

Cancer-Associated Membrane Protein as Targeted Therapy for Bladder Cancer

Bladder cancer (BC) recurrence is one of the primary clinical problems encountered by patients following chemotherapy. However, the mechanisms underlying their resistance to chemotherapy remain unclear. Alteration in the pattern of membrane proteins (MPs) is thought to be associated with this recurrence outcome, often leading to cell dysfunction. Since MPs are found throughout the cell membrane, they have become the focus of attention for cancer diagnosis and treatment. Identifying specific and sensitive biomarkers for BC, therefore, requires a major collaborative effort. This review describes studies on membrane proteins as potential biomarkers to facilitate personalised medicine. It aims to introduce and discuss the types and significant functions of membrane proteins as potential biomarkers for future medicine. Other types of biomarkers such as DNA-, RNA- or metabolite-based biomarkers are not included in this review, but the focus is mainly on cell membrane surface protein-based biomarkers.

A Systematic Review on the Role of Repeat Transurethral Resection after Initial en Bloc Resection for Non-Muscle Invasive Bladder Cancer

International guidelines recommend repeat transurethral resection of bladder tumors (reTURB) for selected patients with high-risk non-muscle invasive bladder cancer to remove possible residual tumors, restage tumors and improve the therapeutic outcome. However, most evidence supporting the benefits of reTURB is from conventional TURB. The role of reTURB in patients receiving initial En bloc resection of bladder tumor (ERBT) is still unknown. PubMed, Embase, Web of Science, The Cochrane Library, and China National Knowledge Infrastructure (CNKI) were systematically searched. Finally, this systematic review and meta-analysis included twelve articles, including 539 patients. The rates of residual tumor and tumor upstaging detected by reTURB after ERBT were 5.9% (95%CI, 2.0%–11.1%) and 0.0% (95%CI, 0.0%–0.5%), respectively. Recurrence-free survival, tumor recurrence and progression were comparable between patients with and without reTURB after initial ERBT. The pooled hazard ratios of 1-year, 2-year, 3-year and 5-year recurrence-free survival were 0.74 (95%CI, 0.36–1.51; p = 0.40), 0.76 (95%CI, 0.45–1.26; p = 0.28), 0.83 (95%CI, 0.53–1.32; p = 0.43) and 0.83 (95%CI, 0.56–1.23; p = 0.36), respectively. The pooled relative risks of recurrence and progression were 0.87 (95%CI, 0.64–1.20; p = 0.40) and 1.11 (95%CI, 0.54–2.32; p = 0.77), respectively. Current evidence demonstrates that reTURB after ERBT for bladder cancer can detect relatively low rates of residual tumor and tumor upstaging and appears not to improve either recurrence or progression.

Modified Titanium Dioxide as a Potential Visible-Light-Activated Photosensitizer for Bladder Cancer Treatment

Low oxygen concentration inside the tumor microenvironment represents a major barrier for photodynamic therapy of many malignant tumors, especially urothelial bladder cancer. In this context, titanium dioxide, which has a low cost and can generate high ROS levels regardless of local O₂ concentrations, could be a potential type of photosensitizer for treating this type of cancer. However, the use of UV can be a major disadvantage, since it promotes breakage of the chemical bonds of the DNA molecule on normal tissues. In the present study, we focused on the cytotoxic activities of a new material (Ti(OH)₄) capable of absorbing visible light and producing high amounts of ROS. We used the malignant bladder cell line MB49 to evaluate the effects of multiple concentrations of Ti(OH)₄ on the cytotoxicity, proliferation, migration, and production of ROS. In addition, the mechanisms of cell death were investigated using FACS, accumulation of lysosomal acid vacuoles, caspase-3 activity, and mitochondrial electrical potential assays. The results showed that exposure of Ti(OH)₄ to visible light stimulates the production of ROS and causes dose-dependent necrosis in tumor cells. Also, Ti(OH)₄ was capable of inhibiting the proliferation and migration of MB49 in low concentrations. An increase in the mitochondrial membrane potential associated with the accumulation of acid lysosomes and low caspase-3 activity suggests that type II cell death could be initiated by autophagic dysfunction mechanisms associated with high ROS production. In conclusion, the characteristics of Ti(OH)₄ make it a potential photosensitizer against bladder cancer.