Long‐term outcomes of outpatient laser ablation for recurrent non‐muscle invasive bladder cancer: A retrospective cohort study

Advanced optical imaging techniques for bladder cancer detection and diagnosis: a systematic review

OBJECTIVES

To systematically assess the current available literature concerning advanced optical imaging methods for the detection and diagnosis of bladder cancer (BCa), focusing particularly on the sensitivity and specificity of these techniques.

METHODS

First a scoping search was performed to identify all available optical techniques for BCa detection and diagnosis. The optical imaging techniques used for detecting BCa are: the Storz professional image enhancement system (IMAGE1 S), narrow-band imaging (NBI), photoacoustic imaging (PAI), autofluorescence imaging (AFI), photodynamic diagnosis (PDD), and scanning fibre endoscopy (SFE). The staging and grading techniques for BCa are: optical coherence tomography (OCT), confocal laser endomicroscopy (CLE), Raman spectroscopy, endocytoscopy, and non-linear optical microscopy (NLO). Then a systematic literature search was conducted using MEDLINE, EMBASE and Web of Science from inception to 21 November 2023. Articles were screened and selected by two independent reviewers. Inclusion criteria were: reporting on both the sensitivity and specificity of a particular technique and comparison to histopathology, and in the case of a detection technique comparison to white light cystoscopy (WLC).

RESULTS

Out of 6707 articles, 189 underwent full-text review, resulting in 52 inclusions. No articles met criteria for IMAGE1 S, PAI, SFE, Raman spectroscopy, and endocytoscopy. All detection techniques showed higher sensitivity than WLC, with NBI leading (87.8-100%). Overall, detection technique specificity was comparable to WLC, with PDD being most specific (23.3-100%). CLE and OCT varied in sensitivity and specificity, with OCT showing higher specificity for BCa diagnosis, notably for carcinoma in situ (97-99%) compared to CLE (62.5-81.3%). NLO demonstrated high sensitivity and specificity (90-97% and 77-100%, respectively) based on limited data from two small ex vivo studies.

CONCLUSIONS

Optical techniques with the most potential are PDD for detecting and OCT for staging and grading BCa. Further research is crucial to validate their integration into routine practice and explore the value of other imaging techniques.

Patient-Reported Outcomes after Laser Ablation for Bladder Tumours Compared to Transurethral Resection-A Prospective Study

The standard procedure for diagnosis and treatment of bladder tumours, transurethral resection of bladder tumour (TURBT), is associated with a complication rate of up to 26% and potentially has severe influence on patient-reported outcomes (PRO). Outpatient transurethral laser ablation (TULA) is an emerging new modality that is less invasive with a lower risk of complications and, thereby, possibly enhanced PRO. We collected PRO following transurethral procedures in treatment of bladder tumours to evaluate any clinically relevant differences in symptoms and side effects. This prospective observational study recruited consecutive patients undergoing different bladder tumour-related transurethral procedures. Patients filled out questionnaires regarding urinary symptoms (ICIQ-LUTS), postoperative side effects, and quality of life (EQ-5D-3L) at days 1 and 14 postoperatively. In total, 108 patients participated. The most frequently reported outcomes were postoperative haematuria and pain. Patients undergoing TURBT reported longer lasting haematuria, a higher perception of pain, and a more negative impact on quality of life compared to patients undergoing TULA. TURBT-treated patients had more cases of acute urinary retention and a higher need for contacting the healthcare system. Side effects following transurethral procedures were common but generally not severe. The early symptom burden following TURBT was more extensive than that following TULA.

Time to progression is the main predictor of survival in patients with high-risk nonmuscle invasive bladder cancer: Results from a machine learning-based analysis of a large multi-institutional database

BACKGROUND

In patients affected by high-risk nonmuscle invasive bladder cancer (HR-NMIBC) progression to muscle invasive status is considered as the main indicator of local treatment failure. We aimed to investigate the effect of progression and time to progression on overall survival (OS) and to investigate their validity as surrogate endpoints.

METHODS

A total of 1,510 patients from 18 different institutions treated for T1 high grade NMIBC, followed by a secondary transurethral resection and BCG intravesical instillation. We relied on random survival forest (RSF) to rank covariates based on OS prediction. Cox's regression models were used to quantify the effect of covariates on mortality.

RESULTS

During a median follow-up of 49.0 months, 485 (32.1%) patients progressed to MIBC, while 163 (10.8%) patients died. The median time to progression was 82 (95%CI: 78.0-93.0) months. In RSF time-to-progression and age were the most predictive covariates of OS. The survival tree defined 5 groups of risk. In multivariable Cox's regression models accounting for progression status as time-dependent covariate, shorter time to progression (as continuous covariate) was associated with longer OS (HR: 9.0, 95%CI: 3.0-6.7; P < 0.001). Virtually same results after time to progression stratification (time to progression ≥10.5 months as reference).

CONCLUSION

Time to progression is the main predictor of OS in patients with high risk NMIBC treated with BCG and might be considered a coprimary endpoint. In addition, models including time to progression could be considered for patients' stratification in clinical practice and at the time of clinical trials design.

Macrophage activity at the site of tumor ablation can promote murine urothelial cancer via transforming growth factor-β1

Cell death and injury at the site of tumor ablation attracts macrophages. We sought to understand the status and activity of these cells while focusing on transforming growth factor-β1 (TGF-β1), a potent immunosuppressive and tumorigenic cytokine. Patients with urothelial cancer who underwent ablation using electrocautery or laser demonstrated increased infiltration and numbers of CD8+ T cells, along with FoxP3+ regulatory T cells, CD68+ macrophages and elevated levels of TGF-β1 in recurrent tumors. Similar findings were reproduced in a mouse model of urothelial cancer (MB49) by partial tumor ablation with irreversible electroporation (IRE). Stimulation of bone marrow derived macrophages with MB49 cell debris produced using IRE elicited strong M2 polarization, with exuberant secretion of TGF-β1. The motility, phenotypic markers and cytokine secretion by macrophages could be muted by treatment with Pirfenidone (PFD), a clinically approved drug targeting TGF-β1 signaling. MB49 cancer cells exposed to TGF-β1 exhibited increased migration, invasiveness and upregulation of epithelial-mesenchymal transition markers α-Smooth Muscle Actin and Vimentin. Such changes in MB49 cells were reduced by treatment with PFD even during stimulation with TGF-β1. IRE alone yielded better local tumor control when compared with control or PFD alone, while also reducing the overall number of lung metastases. Adjuvant PFD treatment did not provide additional benefit under in vivo conditions.

Efficacy of outpatient surveillance in post-intravesical BCG management of high-risk bladder cancer

Background:

Intravesical Bacillus Calmette–Guérin (BCG) instillation is an established form of immunotherapy for intermediate and high-risk bladder cancers. Mandatory cystoscopic surveillance is commonly performed under general anaesthesia (GA) to facilitate biopsy or other procedures. However, it is resource-intensive with unclear clinical benefit.

Methods and patients:

We performed a two-cycle audit, before and after changing post-BCG surveillance policy, from GA cystoscopy to local anaesthetic flexible cystoscopy (LAFC) on trans urethral laser ablation (TULA) lists, where patients may undergo a tumour biopsy or laser ablation. In the first cycle, we audited 53 patients undergoing 114 post-BCG rigid cystoscopies from January 2018 to December 2019. In the second cycle, there were 56 patients undergoing 99 post-BCG LAFCs on TULA lists in 2020.

Results:

In the first audit cycle cohort, the mean patient age was 72.29 ± 8.98 years and 48 were men; malignant histology was identified only on five occasions (three grade progressions). Fourteen patients required overnight admission. In the second audit cycle cohort, the mean patient age was 70.44 ± 9.17 years and 47 were men. Four had a grade progression, while another a stage progression. Out of 99 LAFCs, 47 confirmed normal bladder appearance. A biopsy was taken during other 52 cystoscopies: 17 (33%) confirmed malignancy. Fifteen patients showed findings that were labelled as recurrence, but only two required a further GA procedure to deal with recurrence. One patient was admitted for post-procedure bleeding, which settled with irrigation.

Conclusion:

Local anaesthetic TULA procedure is a safe and effective alternative for a GA rigid cystoscopy to survey bladders of patients on intravesical BCG therapy.

Level of evidence:

3