Photodynamic Diagnosis-guided Dual Laser Ablation for Upper Urinary Tract Carcinoma: Preoperative Preparation, Surgical Technique, and Clinical Outcomes

Henderickx M, van Moorselaar RJA, Kamphuis GM, Baard J. Navigating the Aftermath: A Comprehensive Scoping Review on Follow-up Strategies After Kidney-sparing Surgery for Upper Tract Urothelial Carcinoma

Background and objective

Upper tract urothelial carcinoma (UTUC) can be managed efficiently and safely through kidney-sparing surgery (KSS) in selected patient groups. However, the most effective and efficient postoperative surveillance strategy remains undetermined. We aimed to provide a comprehensive synopsis of the follow-up strategies and survival outcomes in patients diagnosed with UTUC treated by KSS.

Methods

Following the systematic methodology outlined in the Preferred Reporting Items for Systematic Reviews and Meta-analyses Extension for Scoping Reviews, we conducted searches in four databases (MEDLINE [Ovid], Embase [Ovid], Cochrane Library, and Web of Science) up until December 11, 2023.

Key findings and limitations

A total of 3121 articles underwent screening, of which 19 were selected for inclusion in this review. The follow-up schedules after KSS exhibited considerable variability among the included studies. Diagnostic modalities employed consisted of computed tomography urography (present in 84% of protocols), X urography (21%), ultrasound (21%), thoracic imaging (26%), voided urine cytology (89%), selective upper tract cytology (5.3%), cystoscopy (84%), and ureterorenoscopy (53%) at varying frequencies. At 5 yr of follow-up, the reported recurrence-free survival rate ranged from 30% to 86%, overall survival was 50-92%, and metastasis-free survival was 77-90%.

Conclusions and clinical implications

This review unveils significant heterogeneity in clinical practices and survival outcomes, indicating disparities between real-world approaches and guideline recommendations. The lack of consensus on follow-up schemes is evident, emphasising the necessity for future initiatives aimed at developing a comprehensive protocol.

Patient summary

This review shows significant heterogeneity in follow-up strategies after kidney-sparing surgery for upper tract urothelial carcinoma. A lack of evidence contributes to discrepancies between guidelines and real-world approaches. Thus, future endeavours should aim at establishing a comprehensive protocol.

Development and Validation of a Preoperative Nomogram for Endoscopic Management Decision Making in Upper Urinary Tract Urothelial Carcinoma

OBJECTIVE

We aimed to develop and validate a preoperative nomogram that predicts low-grade, non-muscle invasive upper urinary tract urothelial carcinoma (LG-NMI UTUC), thereby aiding in the accurate selection of endoscopic management (EM) candidates.

METHODS

This was a retrospective study that included 454 patients who underwent radical surgery (Cohort 1 and Cohort 2), and 26 patients who received EM (Cohort 3). Utilizing a multivariate logistic regression model, a nomogram predicting LG-NMI UTUC was developed based on data from Cohort 1. The nomogram's accuracy was compared with conventional European Association of Urology (EAU) and National Comprehensive Cancer Network (NCCN) models. External validation was performed using Cohort 2 data, and the nomogram's prognostic value was evaluated via disease progression metrics in Cohort 3.

RESULTS

In Cohort 1, multivariate analyses highlighted the absence of invasive disease on imaging (odds ratio [OR] 7.04; p = 0.011), absence of hydronephrosis (OR 2.06; p = 0.027), papillary architecture (OR 24.9; p < 0.001), and lack of high-grade urine cytology (OR 0.22; p < 0.001) as independent predictive factors for LG-NMI disease. The nomogram outperformed the two conventional models in predictive accuracy (0.869 vs. 0.759-0.821) and exhibited a higher net benefit in decision curve analysis. The model's clinical efficacy was corroborated in Cohort 2. Moreover, the nomogram stratified disease progression-free survival rates in Cohort 3.

CONCLUSION

Our nomogram ( https://kmur.shinyapps.io/UTUC_URS/ ) accurately predicts LG-NMI UTUC, thereby identifying suitable candidates for EM. Additionally, the model serves as a useful tool for prognostic stratification in patients undergoing EM.

450-nm blue diode laser: a novel medical apparatus for upper tract urothelial lesions

OBJECTIVE

To explore the feasibility, safety and effectiveness of the 450-nm blue diode laser (BL), novel blue laser in the treatment of upper tract urothelial carcinomas (UTUCs) and other lesions in a porcine model.

MATERIAL AND METHODS

For in vitro experiment, the ureter tissue was vaporised and coagulated with BL, green-light laser (GL) and Ho:YAG laser (Ho). The efficiency, width and depth of vaporisation, and depth of coagulation were recorded and compared. For in vivo experiments, four swines weighing 70 kg were used. In the acute group, different modes of operations were performed to evaluate the thermal damage, perforation and bleeding. In the chronic group, the overall appearance of the ureter and laser wound healing were observed by the naked eyes and H&E staining 3 weeks after surgery.

RESULTS

In in vitro study, the BL showed a higher efficiency of tissue vaporisation and less tissue coagulation for fresh ureter compared to GL and Ho. In the in vivo study, the power of BL set at 7 W was better, and the thickness of thermal damage varied with different surgery types in the range of 74-306 μm. After 3 weeks, the wound healed well static in vaporisation (SV), moving vaporisation (MV) and H&E staining indicated mucosal healing rather than scar healing.

CONCLUSION

5-10W blue diode laser achieved a higher efficiency of tissue vaporisation and less tissue coagulation in a porcine model, indicating its potential application in the endoscopic surgery of UTUC as an optional device with high performance and safety.

Novel laser therapies and new technologies in the endoscopic management of upper tract urothelial carcinoma: a narrative review

Background and Objective

Upper tract urothelial carcinoma (UTUC) is a rare disease. The gold standard treatment is radical nephroureterectomy (RNU). Endoscopic management of UTUC has emerged as an alternative therapy that aims to preserve kidney function while providing effective oncologic control. Over the years, this has become an increasingly important alternative to RNU for treating UTUC in patients with localized disease. Advancements in lasers and endoscopic technology have continued to expand the applications of endoscopic nephron-sparing treatment. This review aims to provide an overview of the available lasers and ureteroscopic technologies used in treating UTUC with a focus on their clinical applications and outcomes.

Methods

A comprehensive literature review was completed using PubMed to create this narrative mini review. Publications from peer-reviewed journals written in English between 1987 to 2022 were evaluated by the authors for inclusion.

Key Content and Findings

Improvements in ureteroscopic technology have led to improved visualization and tumor detection. Laser ablation using different laser energies including the holmium/yttrium-aluminum-garnet, neodymium/YAG, and thulium/YAG has demonstrated promising oncologic outcomes. However, accurate staging and risk-stratification remain limitations to the role of laser ablation for the treatment of UTUC. This review also highlights appropriate patient selection as a critical component of successful endoscopic management.

Conclusions

The continued evolution of endoscopic management will rely on the development of new technologies to improve risk stratification and oncologic outcomes. Overall, this review provides insights into the available laser therapies and ureteroscopic technologies for the endoscopic management of UTUC.

Learning from the past and present to change the future: Endoscopic management of upper urinary tract urothelial carcinoma

Current guidelines recommend endoscopic management (EM) for patients with low-risk upper urinary tract urothelial carcinoma, as well as those with an imperative indication. However, regardless of the tumor risk, radical nephroureterectomy is still mainly performed worldwide despite the benefits of EM, such as renal function maintenance, no hemodialysis requirement, and treatment cost reduction. This might be explained by the association of EM with a high risk of local recurrence and progression. Furthermore, the need for rigorous patient selection and close surveillance following EM may be relevant. Nevertheless, recent developments in diagnostic modalities, pathological evaluation, surgical devices and techniques, and intracavitary regimens have been reported, which may contribute to improved risk stratification and treatments with superior oncological outcomes. In this review, considering recent advances in endourology and oncology, we propose novel treatment strategies for optimal EM.

A Review of How Lasers Are Used in UTUC Surgery: Can the Choice of Laser Affect Outcomes?

Upper tract urothelial carcinoma (UTUC) is a relatively rare disease with an aggressive phenotype compared to urothelial carcinoma in the bladder. In recent years, kidney-sparing surgery (KSS) and, in particular, endoscopic surgery have become the procedure of choice among urologists where the treatment of localized UTUC is concerned. Endoscopy tends to result in satisfactory oncological disease control while lowering morbidity and minimizing complications amongst the appropriately selected cohort of patients. While endoscopic surgery for UTUC might appear to be standardized, it, in fact, differs considerably depending on the source of energy used for resection/ablation. There has been little reliable data up to now on which laser energy source is the most superior. The goal of this review is, therefore, to outline the results of endoscopic UTUC treatment using different lasers and to analyze how these laser-tissue interactions may affect the surgery. We start by pointing out that the data remains insufficient when trying to determine which laser is the most effective in the endoscopic management of UTUC. The ever-growing number of indications for minimally invasive treatment and the increasing number of centers using laser surgery will, hopefully, lead to novel randomized controlled trials that compare the performance characteristics of the lasers as well as the effects of UTUC on patients.

The role of endoscopic management and adjuvant topical therapy for upper tract urothelial cancer

Upper tract urothelial carcinoma (UTUC) has traditionally been managed with radical nephroureterectomy, and while this approach remains the gold standard for high-risk disease, endoscopic, kidney-sparing management has increasingly been adopted for low-risk disease as it preserves kidney function without compromising oncologic outcomes. Ureteroscopy and percutaneous renal access not only provide diagnoses by tumor visualization and biopsy, but also enable treatment with electrocautery or laser ablation. Several modalities exist for laser ablative treatments including thulium:YAG, neodymium:YAG, holmium:YAG, and combinations of the preceding. Furthermore, due to high recurrence rates after endoscopic management, adjuvant intracavitary instillation of various agents such as mitomycin C and bacillus Calmette-Guerin have been used given benefits seen in non-muscle invasive urothelial bladder cancer. Other formulations also being studied include gemcitabine, anthracyclines, and immunotherapies. More recently, Jelmyto, a mitomycin reverse thermal gel, has been developed to allow for adequate drug delivery time and potency since urine flow could otherwise dilute and washout topical therapy. In this article, the authors review techniques, indications, best practices, and areas of current investigation in endoscopic management and adjuvant topical therapy for UTUC.

A prospective, single-arm trial of fluorescent ureteroscopy-assisted thulium-holmium:YAG dual laser ablation for upper urinary tract cancer: Study protocol of the FLUAM trial

Background

Latest guidelines recommend kidney-sparing management as the primary treatment option for selected patients with upper urinary tract urothelial carcinoma (UTUC). One of the biggest issues of ureteroscopic laser ablation (ULA) is a high rate of surgical site recurrence, which is largely attributed to residual lesions at the initial ULA. Another clinical issue is a significant lack of non-invasive reliable detection tools of urinary recurrent tumors in this treatment setting.

Methods

The FLUAM trial is a prospective, single-center, single-arm pilot trial to investigate the efficacy of 5-aminolevulinic acid-mediated photodynamic diagnosis (ALA-PDD)-assisted ULA for localized UTUC and the usefulness of the UroVysion® assay (multiprobe fluorescence in situ hybridization) as a monitoring test after the kidney-sparing treatment. After the screening and registration, a total of 20 patients with localized UTUC will undergo the initial ALA-PDD-assisted ULA followed by the second look ALA-PDD-assisted ureteroscopic examination. The primary endpoint is progression-free survival. Secondary endpoints include patient reported outcomes, diagnostic accuracy of UroVysion assay to detect tumor recurrence, adverse events, and safety of the intervention.

Conclusion

The goal of this trial is to determine the potential benefit of ALA-PDD assistance in patients who undergo the ULA. The evidence of this novel technique is still limited. The results are expected to change the standard of care and lead to better management of localized UTUC.

Trial registration

This clinical trial was prospectively registered with the Japan Registry of Clinical Trials on 23 June 2021. The reference number is jRCTs051210042, nara0023 (Certified Review Board of Nara Medical University).