Effectiveness and Safety of Thulium Fiber Laser in the Conservative Management of Patients with Upper Tract Urothelial Carcinoma

Emerging strategies: conservative management of upper tract urothelial carcinoma

PURPOSE OF REVIEW

Upper tract urothelial carcinoma (UTUC) is a rare yet aggressive malignancy, representing 5-10% of urothelial cancers. While radical nephroureterectomy (RNU) has traditionally offered excellent oncological control, it compromises renal function. Recent advancements have shifted the paradigm toward kidney-sparing strategies in select cases. This review highlights innovations in UTUC diagnosis and conservative management, focusing on emerging imaging techniques, noninvasive biomarkers, and minimally invasive treatments.

RECENT FINDINGS

Advances in multiparametric MRI and radiomics have improved diagnostic accuracy and risk stratification. Moreover, noninvasive biomarkers - including circulating tumor DNA, microRNAs, and urinary methylation assays - provide promising tools for early detection and surveillance. Kidney-sparing approaches such as endoscopic laser ablation and segmental ureterectomy have demonstrated comparable oncologic outcomes in low-risk patients. Moreover, topical therapies, including intracavitary treatments like UGN-101, offer a promising minimally invasive option.

SUMMARY

The conservative management of UTUC is evolving, driven by advancements in imaging, molecular diagnostics, and minimally invasive treatments. While kidney-sparing approaches are increasingly utilized in low-risk patients, further prospective studies are needed to validate their efficacy.

[Organ-preserving treatment for urothelial carcinoma of the upper urinary tract]

Urothelial carcinoma of the upper urinary tract is rare but the incidence is currently increasing in western countries. Radical nephroureterectomy has long been the standard treatment; however, it can lead to chronic kidney failure and also the necessity for dialysis. Therefore, organ-preserving treatment is now recommended for selected patients with low-risk tumors. The choice of treatment depends on the tumor characteristics, comorbidities and individual risk factors. Surgical options for organ preservation include ureterorenoscopy (URS), percutaneous treatment and partial ureteral resection. The URS is the most frequently used method for organ preservation. Photodynamic diagnostics (PDD) and narrow band imaging (NBI) can potentially also be used for tumor detection in the upper urinary tract. Conservative options such as topical treatment with mitomycin C or Bacillus Calmette-Guérin (BCG) and systemic treatment options are also possible.

Outcomes of Radical Radiotherapy for the Treatment of Localized Renal Pelvic and Ureteral Carcinoma Intolerant to Surgery: A Real-World Study

PURPOSE

To investigate the safety and efficacy of radical radiotherapy for localized inoperable renal pelvic and ureteral carcinoma.

METHODS

23 patients who received radiotherapy were enrolled. The prescribed dose was 60 to 67.5 Gy in 25 fractions and for bulky tumors, SABR was used in the first 3 to 5 times with tumor center boosted synchronously with 6 to 8 Gy/f. The Kaplan-Meier method was used to calculate local control (LC), DMFS, CSS and OS. Univariate analysis was performed by the log-rank test. The change in the eGFR before and after radiotherapy was compared by paired t test. The side effects were graded by CTCAE, version 5.0.

RESULTS

The median follow-up time was 17 months. The LC rates at 2 years after radiotherapy were 85.0%; the DMFS rates were 52.2%; the CSS rates were 83.0%; and the OS rates were 77.8%. The main failure mode after radiotherapy was distant metastasis. Univariate analysis revealed that T3-4 stage (P = .001), N+ status (P < .001) and a tumor volume ≥ 20 cc (P = .005) were poor prognostic factors for DMFS. There was no significant difference in the mean eGFR before and after radiotherapy (47.0 mL/min/1.73m2 vs. 48.5 mL/min/1.73m2, P = .632). Only 1 patient developed acute grade 3 anemia. No patients developed grade 3 or higher late toxicities.

CONCLUSION

For localized inoperable renal pelvic and ureteral carcinoma, radiotherapy is well tolerable with high local control and expected to bring survival benefits. In such patients, radiotherapy may be an option when surgery is unsuitable.

Cumulative morbidity of ureteroscopy for upper tract urothelial carcinoma

OBJECTIVE

To assess complications after ureteroscopy (URS) for upper tract urothelial carcinoma (UTUC) management and to assess its postoperative cumulative morbidity burden using the Comprehensive Complication Index (CCI).

MATERIALS AND METHODS

Single center retrospective study including patients submitted to URS for UTUC suspicion. URSs were both diagnostic and operative. Postoperative complications were recorded according to the EAU Guidelines and graded according to Clavien-Dindo Classification (CDC). The cumulative postoperative morbidity burden developed by patients experiencing multiple events was assessed using the CCI. Multivariable logistic regression (MLR) analyses identified factors independently associated with the development of any grade and major postoperative complications.

RESULTS

Overall, 360 patients with UTUC suspicion were included with a total of 575 URSs performed. The cumulative number of all postoperative complications recorded was 111. In 86 (15%) procedures, patients experienced at least one postoperative complication, while 25 (4.3%) experienced more than one complication. Of these, 16 (14%) were severe (CDC ≥ IIIa). The most frequent type of complications were urinary (34%), bleeding (30%) and infectious (30%). The higher the CDC grade, the higher the median CCI, with a statistically significant increase in median CCI from CDC II to major complications. Patients who experienced intraoperative complications were at higher risk of developing any grade and major postoperative complications at MLR.

CONCLUSIONS

Complications after ureteroscopy for UTUC are relatively uncommon events. Patients who experience intraoperative complications are at higher risk of developing postoperative complications. The comprehensive complication index appeared more representative of the cumulative postoperative morbidity rather than the Clavien-Dindo classification.

Current Evidence on Utility, Outcomes, and Limitations of Endoscopic Laser Ablation for Localized Upper Urinary Tract Urothelial Carcinoma: Results from a Scoping Review

Context

The occurrence of upper urinary tract urothelial carcinoma (UTUC) is uncommon and is usually identified at an advanced and multifocal stage. Currently, there is growing interest in utilizing endoscopic laser ablation (ELA).

Objective

To evaluate the survival rates and perioperative complications of ELA.

Evidence acquisition

We performed a literature search through PubMed, Web of Science, and Scopus. The analysis included observational studies that examined the oncological outcomes of patients with UTUC treated with ELA.

Evidence synthesis

Neodymium and diode lasers are no longer used due to their high complication rates. Holmium:yttrium-aluminum-garnet (YAG) and thulium:YAG lasers provided excellent tumor ablation and hemostasis in both the collecting system and the ureter. These lasers offer good disease-free and cancer-specific survival, especially for low-grade tumors.

Conclusions

Advancements in laser technology and ablation techniques, and understanding of UTUC tumor biology hold significant promise in improving the use of conservative UTUC treatment, with excellent safety and good oncological outcomes for low-grade diseases.

Patient summary

With the advancement of technology, the conservative approach utilizing endoscopic laser ablation for upper tract urothelial tumors has been proved to be both safe and effective, showcasing promising survival rates.

Advances in lasers for the minimally invasive treatment of upper and lower urinary tract conditions: a systematic review

PURPOSE

Technological advancements in laser lithotripsy are expanding into numerous fields of urology, like ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), and benign and malignant soft-tissue treatments. Since the amount of research regarding lasers in urology has grown exponentially, we present a systematic review of the most recent and relevant advances encompassing all lasers used in urological endoscopic treatment.

METHODS

We performed a literature search using PubMed (May 2023) to obtain information about lasers for urological purposes. We included only recent data from published articles between 2021 and 2023 or articles ahead of print.

RESULTS

Lasers are widely used in lithotripsy for ureteric, renal, and bladder stones, benign prostate surgery, and bladder and upper tract tumor ablation. While the holmium (Ho:YAG) laser is still predominant, there seems to be more emphasis on pulse modulation and newer lasers such as thulium fiber laser (TFL) and pulsed Tm:YAG laser.

CONCLUSION

The use of lasers and related technological innovations have shown increasing versatility, and over time have proven to be invaluable in the management of stone lithotripsy, treatment of benign and malignant prostate diseases, and urothelial tumors. Laser endoscopic treatment is heavily based on technological nuances, and it is essential to know at least the basics of these technologies. Ultimately the choice of laser used depends on its availability, cost, surgeon experience and expertise.

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.

Experts' recommendations in laser use for the treatment of upper tract urothelial carcinoma: a comprehensive guide by the European Section of Uro-Technology (ESUT) and Training Research in Urological Surgery and Technology (T.R.U.S.T.) group

PURPOSE

To highlight and compare experts' laser settings during endoscopic laser treatment of upper tract urothelial carcinoma (UTUC), to identify measures to reduce complications, and to propose guidance for endourologists.

METHODS

Following a focused literature search to identify relevant questions, a survey was sent to laser experts. We asked participants for typical settings during specific scenarios (ureteroscopy (URS), retrograde intrarenal surgery (RIRS), and percutaneous treatment). These settings were compared among the reported laser types to find common settings and limits. Additionally, we identified preventive measures commonly applied during surgery.

RESULTS

Twenty experts completed the survey, needing a mean time of 12.7 min. Overall, most common laser type was Holmium-Yttrium-Aluminum-Garnet (Ho:YAG) (70%, 14/20) followed by Thulium fiber laser (TFL) (45%, 9/20), pulsed Thulium-Yttrium-Aluminum-Garnet (Tm:YAG) (3/20, 15%), and continuous wave (cw)Tm:YAG (1/20, 5%). Pulse energy for the treatment of distal ureteral tumors was significantly different with median settings of 0.9 J, 1 J and 0.45 J for Ho:YAG, TFL and pulsed Tm:YAG, respectively (p = 0.048). During URS and RIRS, pulse shapes were significantly different, with Ho:YAG being used in long pulse and TFL in short pulse mode (all p < 0.05). We did not find further disparities.

CONCLUSION

Ho:YAG is used by most experts, while TFL is the most promising alternative. Laser settings largely do not vary significantly. However, further research with novel lasers is necessary to define the optimal approach. With the recent introduction of small caliber and more flexible scopes, minimal-invasive UTUC treatment is further undergoing an extension of applicability in appropriately selected patients.

Advances in chemoablation in upper tract urothelial carcinoma: overview of indications and treatment patterns

Localized upper tract urothelial carcinoma (UTUC) is a difficult disease for clinicians to treat, due to the multitude of oncological and patient factors to consider. Despite the challenges of diagnostic staging, endoscopic management, and disease recurrence, there is still a need for local therapeutic options that do not subject patients to the morbidities of radical nephroureterectomy (RNU). Intraluminal chemotherapies have allowed for improved oncological control in patients with low-grade disease receiving renal-sparing treatment approaches. This narrative review discusses the treatment modalities available for localized low-grade UTUC, with a focus on the current status of chemoablation. The OLYMPUS trial was a pivotal study that lead to the Food and Drug Administration (FDA) approval of UGN-101 (mitomycin-C) in April 2020 for the treatment of low-grade UTUC, and intraluminal chemotherapy is now a widely used modality for managing this disease. The trial reported a complete response (CR) rate of 59%, and an estimated treatment durability of 82% at 1 year. However, a concern was the reported 44% ureteral stricture rate using the retrograde approach. More research is currently underway to determine the ideal instillation method for intraluminal therapies (e.g., retrograde vs. antegrade). Lastly, we discuss upcoming treatment options. Newer novel agents like padeliporfin vascular targeted photodynamic (VTP) therapy (brand name TOOKAD) are currently being studied, which will in hope provide additional treatment options for UTUC patients.

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.

Endoscopic Conservative Treatment of Upper Urinary Tract Urothelial Carcinoma with a Thulium Laser: A Systematic Review

INTRODUCTION

Thulium lasers (TLs), namely the Thulium fiber laser (TFL) and the Thulium:YAG (Tm:YAG), are being increasingly adopted for the conservative treatment of upper urinary tract urothelial carcinoma (UTUC). However, to date, the real clinical impact of TLs on UTUC management remains not well-characterized. We performed a review of the literature to summarize the current evidence on TLs for UTUC treatment.

MATERIALS AND METHODS

We performed a systematic review in January 2023 using the Embase and Medline online databases, according to the PRISMA recommendations and using the PICO criteria. Outcomes of interest were: (i) to assess the safety and feasibility of TLs in the treatment of UTUC, and (ii) to evaluate the oncological outcomes in terms of tumor recurrence and conservative treatment failure. Moreover, we described TL characteristics and its interaction with soft tissue.

RESULTS

a total of 458 articles were screened, and six full texts including 273 patients were identified. All the included studies were retrospective series. Mean patient age ranged from 66 to 73 years. The indication of a conservative treatment was elective and imperative in 21.7-85% and 15-76% of cases, respectively. Laser power settings varied from 5 to 50 W. No intraoperative complications were reported, and all the procedures were successfully performed. The tumor recurrence rate was 17.7-44%, and the indication to radical nephroureterectomy was 3.7-44% during a follow-up of 6-50 months. Most of the postoperative complications were mild and transient, and ureteral strictures were reported in two studies. Major limitations were the retrospective nature of the studies, the small sample sizes, and the short follow-up.

CONCLUSIONS

TL is an effective and safe technology for endoscopic UTUC treatment. However, current available literature lacks prospective and multicentric studies with large population sizes and long-term follow-up.