Endoscopic Treatment for Large Multifocal Upper Tract Urothelial Carcinoma

Automated Upper Tract Urothelial Carcinoma Tumor Segmentation During Ureteroscopy Using Computer Vision Techniques

Introduction: Endoscopic tumor ablation of upper tract urothelial carcinoma (UTUC) allows for tumor control with the benefit of renal preservation but is impacted by intraoperative visibility. We sought to develop a computer vision model for real-time, automated segmentation of UTUC tumors to augment visualization during treatment. Materials and Methods: We collected 20 videos of endoscopic treatment of UTUC from two institutions. Frames from each video (N = 3387) were extracted and manually annotated to identify tumors and areas of ablated tumor. Three established computer vision models (U-Net, U-Net++, and UNext) were trained using these annotated frames and compared. Eighty percent of the data was used to train the models while 10% was used for both validation and testing. We evaluated the highest performing model for tumor and ablated tissue segmentation using a pixel-based analysis. The model and a video overlay depicting tumor segmentation were further evaluated intraoperatively. Results: All 20 videos (mean 36 ± 58 seconds) demonstrated tumor identification and 12 depicted areas of ablated tumor. The U-Net model demonstrated the best performance for segmentation of both tumors (area under the receiver operating curve [AUC-ROC] of 0.96) and areas of ablated tumor (AUC-ROC of 0.90). In addition, we implemented a working system to process real-time video feeds and overlay model predictions intraoperatively. The model was able to annotate new videos at 15 frames per second. Conclusions: Computer vision models demonstrate excellent real-time performance for automated upper tract urothelial tumor segmentation during ureteroscopy.

Endoscopic excision versus radical nephroureterectomy for non-muscle invasive upper tract urothelial carcinoma: A population-based large cohort study

Background

As an important kidney-sparing treatment for upper urothelial carcinoma (UTUC), whether endoscopic excision can be performed without sacrificing oncologic outcomes remains indefinite. This study aimed to investigate the prevalence and efficacy of endoscopic excision, in patients with non-muscle invasive UTUC (NMIUTUC) and compare them to those of radical nephroureterectomy (RNU).

Methods

Using the Surveillance, Epidemiology, and End Results database, we reviewed 4347 cases with NMIUTUC (cTis/Ta/T1-N0-M0,≤ 5.0 cm) between 2004 and 2020. Surgical treatment modalities included endoscopic excision and RNU. Propensity score matching analysis was used to minimize the selection bias between endoscopic excision and RNU, selecting 1:1 matched patients in the two group.

Results

A total of 794 patients with NMIUTUC were included after matching (397:397). Patients who underwent endoscopic excision had worse survival outcomes compared with those of patients who underwent RNU (5-year OS: 65.3 % vs. 80.3 %, p < 0.0001; 5-year DSS: 83.2 % vs. 94.0 %, p = 0.00021). After stratification by anatomical sites, the effect of endoscopic excision for NMI renal pelvis cancer was worse than RNU (5-year OS, 62.9 % vs. 82.8 %; 5-year DSS, 78.8 % vs. 91.6 %), while in NMI ureteral cancer, there is no statistically significant difference in OS and DSS between endoscopic excision and RNU. Further stratification according to tumor grade revealed equivalent tumor control effects of endoscopic excision and RNU in low-grade NMI ureteral cancer (5-year OS: 67.7 % vs. 72.5 %, p = 0.23; 5-year DSS: 87.2 % vs. 93.1 %, p = 0.17); while for renal pelvis tumor and high-grade ureteral tumor, endoscopic excision was related with significantly inferior prognosis.

Conclusions

Only for low-grade NMI ureteral cancer, endoscopic excision and RNU are oncologically equivalent, indicating that endoscopic excision might be an effective option for low-grade NMI ureteral cancer. This result needs to be further verified in randomized controlled trials.

The ablative effect of mitomycin reverse thermal gel: Expanding the role for nephron preservation therapy in low grade upper tract urothelial carcinoma

PURPOSE

Assess the real-world ablative effect of mitomycin reverse thermal gel for low-grade upper tract urothelial carcinoma (UTUC) in patients who undergo biopsy only or partial ablation and evaluate utility of complete ablation prior to UGN-101.

MATERIAL AND METHODS

We retrospectively reviewed low-grade UTUC patients treated with UGN-101 from 15 high-volume centers. Patients were categorized based on initial endoscopic ablation (biopsy only, partial ablation, or complete ablation) and by size of remaining tumor (complete ablation, <1cm, 1-3cm, or >3cm) prior to UGN-101. The primary outcome was rendered disease free (RDF) rate at first post-UGN-101 ureteroscopy (URS), defined as complete response or partial response with minimal mechanical ablation to endoscopically clear the upper tract of visible disease.

RESULTS

One hundred and sixteen patients were included for analysis after excluding those with high-grade disease. At first post-UGN-101 URS, there were no differences in RDF rates between those who at initial URS (pre-UGN-101) had complete ablation (RDF 77.0%), partial ablation (RDF 55.9%) or biopsy only (RDF 66.7%) (P = 0.14). Similarly, a complimentary analysis focusing on tumor size (completely ablated, <1cm, 1-3cm or >3cm) prior to UGN-101 induction did not demonstrate significant differences in RDF rates (P = 0.17).

CONCLUSION

The results of the early real-world experience suggest that UGN-101 may play a role in initial chemo-ablative cytoreduction of larger volume low-grade tumors that may not initially appear to be amenable to renal preservation. Further studies will help to better quantify the chemo-ablative effect and to identify clinical factors for patient selection.

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.

Strategies of Endoscopic Management of Upper Tract Urothelial Carcinoma among Endourologists: A Global Survey

Up-to-date guidelines on the management of upper tract urothelial carcinoma (UTUC) are continuously published. We aim to assess the variability of diagnosis and treatment strategies in the endoscopic management of UTUC and adherence to European Association of Urology and National Comprehensive Cancer Network guidelines. A 15-question survey was designed to query practitioners on approaches to clinical practice and knowledge about endoscopic treatment indications and techniques. It was emailed to all members of the Endourologic Society through the society’s office, and to all Israeli non-member endourologists. Eighty-eight urologists participated in the survey. Adherence to guidelines on indications for endoscopic management was only 51%. Most of the survey respondents (87.5%) use holmium laser for tumor ablation, and ~50% use forceps for biopsy while the other half use baskets. Only 50% stated that they would use Jelmyto® for specific indications. Most (80%) indicated that they repeat the ureteroscopy 3 months after the first one, and 52.3% continue with follow-up ureteroscopy every 3 months during the first year after diagnosis. There is vast variability among endourologists in the technical aspects of UTUC, the indications for endoscopic management, and adherence to the available guidelines for managing UTUC.

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.

Oncologic and Safety Outcomes for Retrograde and Antegrade Endoscopic Surgeries for Upper Tract Urothelial Carcinoma: A Systematic Review and Meta-analysis

The aim of this study was to identify and summarize available data on oncologic and safety outcomes for retrograde versus antegrade endoscopic surgery in patients with upper tract urothelial carcinoma (UTUC). We systematically searched studies reporting on endoscopic surgery in patients with UTUC. The primary outcome of interest was oncologic control, including bladder and upper urinary tract recurrences. The secondary outcomes were any-grade and major complications. Twenty studies comprising 1091 patients were included in our analysis. The pooled bladder recurrence rate was 35% (95% confidence interval [CI] 28.0-42.3%; I² = 48%) after retrograde endoscopic surgery and 17.7% (95% CI 6.5-32.1%; I² = 29%) after antegrade endoscopic surgery. The pooled upper urinary tract recurrence rate was 56.4% (95% CI 41.2-70.9; I² = 93%) after retrograde endoscopic surgery and 36.2% (95% CI 25.5-47.6%; I² = 57%) after antegrade endoscopic surgery. The pooled complication rate was 12.5% (95% CI 0.8-32.8%; I² = 94%) for any-grade complications and 6.6% (95% CI 0.1-19.1%; I² = 89%) for major complications in the retrograde endoscopic cohort. In summary, our analyses suggest promising oncologic benefits of antegrade kidney-sparing surgery in terms of bladder and upper urinary tract recurrence rates in UTUC. Retrograde endoscopic surgery is a safe procedure with a minimal risk of complications and acceptable oncologic outcomes. Research should address the hypothesis that endoscopic antegrade surgery can be a safe and effective alternative for well-selected patients. PATIENT SUMMARY: One of the surgical options for treatment of cancer of the upper urinary tract is removal of the tumor through a small telescope called an endoscope. The endoscope can be inserted via the urethra (called a retrograde approach) or through a small incision in the skin (antegrade approach). Our review shows that the antegrade approach seems to provide acceptable cancer control rates. Further research could help to identify the role for endoscope surgery in cancer of the upper urinary tract.

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.

Endoscopic Ablation of Upper Tract Urothelial Carcinoma: A Report of Two Cases with Long Disease Recurrence-Free Periods

Upper tract urothelial carcinoma (UTUC) is a relatively rare disease that accounts for 5% to 10% of all urothelial carcinomas (UCs). Radical nephroureterectomy (RNU) with a bladder cuff is the current gold standard for the management of UTUC; however, endoscopic ablation is also an option for low-risk UTUC to preserve kidney function. Herein, we present two cases of solitary kidney with a right lower ureteral tumor. Both patients underwent left RNU in the past. An 82-year-old man with a right ureteral tumor whose histopathological examination revealed low-grade UC. Laser ablation was performed with ureteroscopy, and there was no recurrence for 7 years after treatment. A 67-year-old woman with a right lower ureteral tumor whose histopathological examination also revealed low-grade UC. Laser ablation was performed, and there was no recurrence for 5 years after the treatment. We closely followed-up our two patients after RNU. This allowed for early detection of tumor recurrence, after which we could perform laser ablation therapy.

Management of Upper Tract Urothelial Carcinoma

PURPOSE OF REVIEW

We review the epidemiology, risk factors, diagnosis, and treatment of upper tract urothelial carcinoma (UTUC), with a distinction between the different risk groups.

RECENT FINDINGS

Endoscopic treatment with laser ablation of tumors has an evolving role in treating low-grade UTUC including select large and multifocal tumors, along with complementary topical chemotherapeutic treatment that can reach difficult intrarenal locations. Template lymphadenectomy is recommended in patients undergoing nephroureterectomy. A recent randomized control trial showed benefit of adjuvant chemotherapy after radical nephroureterectomy for locally advanced disease. Advances in immunologic therapy have shown promise in treating metastatic UTUC, and immunologic-based therapies have been incorporated into treatment regimens. Notable progress has been made in both the surgical and medical treatment arms for UTUC, thus extending the reach of nephron-sparing therapy for those with localized disease and increasing overall survival for those with locally advanced disease.

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

Background

Although ureteroscopic surgery (URS) is beneficial for low-risk upper urinary tract carcinoma (UTUC), there is no standardized URS technique or navigation system for challenging cases.

Objective

To present a URS technique for UTUC using thulium (Tm):YAG and holmium (Ho):YAG lasers under photodynamic diagnosis (PDD) guidance, named PDD-guided dual laser ablation (PDD-DLA) and compare its efficacy with that of conventional Ho:YAG laser ablation (HLA; historical control).

Design, setting, and participants

The study included ten consecutive UTUC patients who underwent PDD-DLA between 2017 and 2019. The control group comprised 16 consecutive patients who underwent HLA between 2006 and 2016.

Surgical procedure

After oral administration of 5-aminolevulinic acid (20 mg/kg), UTUC tumors were endoscopically resected via PDD-DLA.

Measurements

Clinical data were prospectively collected for our institutional UTUC data set. Disease progression, UTUC recurrence, and clinical outcomes were assessed.

Results and limitations

PDD-DLA was successfully performed in all patients. The median tumor size was 23.5 mm (interquartile range [IQR] 12.8–30.0) and there were four cases (40.0%) of high-grade tumor. The median operative time was 120 min (IQR 98.5–142.5). No Clavien-Dindo grade ≥3 complications were observed. There were no differences in most clinical characteristics between the PDD-DLA and HLA groups. The 2-yr progression-free survival rate was 100% in the PDD-DLA group and 58.7% in the HLA group (p = 0.0197), and the 2-yr recurrence-free survival rate was 57.1% and 41.3%, respectively (p = 0.072). The PDD-DLA group had a lower incidence rate of salvage RNU compared with the HLA group (0.0% vs 50%; p = 0.009). The small sample size might affect the reproducibility of these results.

Conclusions

PDD-DLA seems to be an effective and feasible endoscopic technique for UTUC treatment with favorable oncological outcomes.

Patient summary

We investigated a new laser technique for treating cancer of the upper urinary tract called photodynamic diagnosis–guided dual laser ablation. Our strategy was effective in removing tumors and stopping bleeding. Further studies in larger groups of patients are needed to confirm whether this technique improves cancer outcomes.

Endoscopic exploration directly impacts clinical decision making in the management of patients with suspected upper tract urothelial carcinoma following radical cystectomy

OBJECTIVES

To assess whether the use of endoscopic exploration (EE) as a routine diagnostic tool in patients with clinical suspicion of upper tract urothelial carcinoma (UTUC) following radical cystectomy (RC) significantly impacts management decision-making and to describe the oncological outcomes of patients with UTUC after RC.

MATERIALS AND METHODS

We performed a retrospective review of medical records of patients with suspicion of UTUC after RC between 2000 and 2019. Patient demographics, clinicopathological features, treatments, and outcomes were analyzed.

RESULTS

We identified 60 patients with suspicion of UTUC. After diagnostic work-up, 16 were submitted to radical nephroureterectomy (RNU) and 44 underwent diagnostic EE. After EE, a further 18/44 (40.9%) were submitted to RNU, while no evidence of tumor was found in 12 (27.3%) and the remaining 12 (27.3%) underwent endoscopic treatment (ET). Thus, in 24/44 (54.5%) patients the primary treatment strategy, i.e., RNU, was altered. Twenty-nine (85.3%) of the 34 patients who underwent RNU had high-grade tumors and 16 (47%) had the muscle-invasive disease. In the ET group, 6 (50%) had high-grade tumors and 10 (83.4%) had tumors less than 2 cm. The 5-year estimated recurrence-free survival and cancer-specific survival were, respectively, 58.4% and 45.6% in the RNU group and 25% and 80.8% in the ET group.

CONCLUSION

EE significantly impacts clinical decision-making in patients with suspicion of UTUC after RC, resulting in a change in treatment strategy in approximately half of the patients. UTUC following RC has a poor prognosis and although RNU is the gold standard, ET could be considered in a selected group of patients.