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

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.

Kidney-Sparing Management of UTUC in Solitary Kidney Patients: A Retrospective Analysis and Narrative Review

Background/Objectives: The aim of this study is the presentation of an endoscopic therapeutic approach for three patients with a solitary kidney who were diagnosed with urothelial cancer of the upper tract. Methods: This retrospective analysis included patients with solitary kidneys who suffered from high-grade UTUC (urothelial cancer of the upper urinary tract) and underwent conservative treatment. Results: The first patient was a 67-year-old male who had a prior history of a nephroureterectomy due to UTUC six years ago. The patient was diagnosed with high-grade UTUC in the contralateral kidney. The tumor has been managed with endoscopic ablation. The second patient was a 74-year-old male with a non-functional kidney and high-grade UTUC diagnosed in the contralateral side. The patient underwent endoscopic ablation for the tumor. The third case was a 68-year-old female patient who had a history of a nephroureterectomy due to UTUC. Afterward, she was diagnosed with high-grade UTUC in the contralateral kidney. The patient was treated with percutaneous tumor resection and the placement of a nephrostomy tube. The first patient was included in an immunotherapy program based on an oncologist consultation after laser ablation treatment for Ta high-grade UTUC, followed by the endoscopic management of two recurrences. Afterward, no recurrence was detected. The remaining two patients followed up without the detection of a new recurrence. Conclusions: The kidney-sparing approach (tumor laser ablation or resection) for high-risk UTUC treatment in selected patients with solitary kidneys seems to provide adequate early outcomes in relation to preserving renal function and effective disease management. It is important to personalize the way of treatment in every case after a thorough examination of the patient's data.

The Utility of Intraluminal Therapies in Upper Tract Urothelial Carcinoma: A Narrative Review

Nephron sparing surgery (NSS) is considered for selected cases of upper tract urothelial carcinoma (UTUC) as it maintains renal function and avoids morbidity associated with radical nephroureterectomy (RNU). The appropriate selection of patients suitable for NSS without compromising oncological outcomes can sometimes be difficult, given the limitations of diagnostic modalities. Recurrence rates for UTUC can be as high as 36 to 54% after NSS. Intraluminal adjuvant therapy can be attempted following NSS to reduce recurrence, but delivery to the upper tract is more challenging than into the bladder. Bacillus Calmette-Guerin (BCG) and chemotherapy such as Mitomycin (MMC) have been administered via nephrostomy or ureteric catheter, which requires invasive/repeated instrumentation of the upper urinary tract. Drug delivery by reflux from bladder instillation along indwelling stents has also been tried but can potentially be unreliable. Recently, a gel formulation of mitomycin has been developed for the controlled exposure of the upper urinary tract to treatment over a number of hours. Drug-eluting stents to deliver chemotherapy to the upper urinary tract have been developed but have not yet entered clinical practice. Endoluminal phototherapy utilising an intravenous photosensitising agent is another novel approach that has recently been described. Intraluminal therapies may be beneficial in decreasing recurrence rates in UTUC, but currently have some limitations in their usage.

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.

Upper Tract Urothelial Carcinoma: A Narrative Review of Current Surveillance Strategies for Non-Metastatic Disease

Non-metastatic upper urinary tract carcinoma (UTUC) is a comparatively rare condition, typically managed with either kidney-sparing surgery (KSS) or radical nephroureterectomy (RNU). Irrespective of the chosen therapeutic modality, patients with UTUC remain at risk of recurrence in the bladder; in patients treated with KSS, the risk of recurrence is high in the remnant ipsilateral upper tract system but there is a low but existent risk in the contralateral system as well as in the chest and in the abdomen/pelvis. For patients treated with RNU for high-risk UTUC, the risk of recurrence in the chest, abdomen, and pelvis, as well as the contralateral UT, depends on the tumor stage, grade, and nodal status. Hence, implementing a risk-stratified, location-specific follow-up is indicated to ensure timely detection of cancer recurrence. However, there are no data on the type and frequency/schedule of follow-up or on the impact of the recurrence type and site on outcomes; indeed, it is not well known whether imaging-detected asymptomatic recurrences confer a better outcome than recurrences detected due to symptoms/signs. Novel imaging techniques and more precise risk stratification methods based on time-dependent probabilistic events hold significant promise for making a cost-efficient individualized, patient-centered, outcomes-oriented follow-up strategy possible. We show and discuss the follow-up protocols of the major urologic societies.

Modern Kidney-Sparing Management of Upper Tract Urothelial Carcinoma

PURPOSE

To review the latest evidence on the modern techniques and outcomes of kidney-sparing surgeries (KSS) in patients with upper tract urothelial carcinoma (UTUC).

METHODS

A comprehensive literature search on the study topic was conducted before 30 April 2023 using electronic databases including PubMed, MEDLINE, and EMBASE. A narrative overview of the literature was then provided based on the extracted data and a qualitative synthesis of the findings.

RESULTS

KSS is recommended for low- as well as select high-risk UTUCs who are not eligible for radical treatments. Endoscopic ablation is a KSS option that is associated with similar oncological outcomes compared with radical treatments while preserving renal function in well-selected patients. The other option in this setting is distal ureterectomy, which has the advantage of providing a definitive pathological stage and grade. Data from retrospective studies support the superiority of this approach over radical treatment with similar oncological outcomes, albeit in select cases. Novel chemoablation agents have also been studied in the past few years, of which mitomycin gel has received FDA approval for use in low-risk UTUCs.

CONCLUSION

KSSs are acceptable approaches for patients with low- and select high-risk UTUCs, which preserve renal function without compromising the oncological outcomes.

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.

Need for and extent of lymph node dissection for upper tract urothelial carcinoma: an updated review in 2023

PURPOSE OF REVIEW

Although lymph node dissection (LND) during radical nephroureterectomy (RNU) is recommended for high-risk nonmetastatic upper tract urothelial carcinoma (UTUC), adherence to guidelines remains insufficient in clinical practice. Therefore, this review aims to comprehensively summarize the current evidence regarding the diagnostic, prognostic, and therapeutic impact of LND during RNU in UTUC patients.

RECENT FINDINGS

Clinical nodal staging using conventional CT scan has low sensitivity (25%) and diagnostic accuracy [area under the curve (AUC): 0.58] in UTUC, suggesting the importance of LND for obtaining accurate N-staging. Patients with pathological node-positive (pN+) disease have poor disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) compared with those with pN0. In addition, population-based studies showed that patients who underwent LND improved CSS and OS than those who did not, even in patients who received adjuvant systemic therapy. The number of lymph nodes removed has also been shown to be associated with improved CSS and OS, even in pT0 patients. Template-based LND should be performed as the extent of lymph node is more important than the number of lymph nodes. Robot-assisted RNU may facilitate performing a meticulous LND compared with a laparoscopic approach. Postoperative complications such as lymphatic and/or chylous leakage are increased but adequately manageable. However, the current evidence is not supported by high-quality studies.

SUMMARY

Based on the published data, LND during RNU is a standard procedure for high-risk nonmetastatic UTUC, owing to its diagnostic, staging, prognostic, and, potentially, therapeutic benefits. Template-based LND should be offered to all patients who are planned for RNU for high-risk nonmetastatic UTUC. Patients with pN+ disease are optimal candidates for adjuvant systemic therapy. Robot-assisted RNU may facilitate meticulous LND compared with laparoscopic RNU.

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.