Current Knowledge on Genomic Profiling of Upper Tract Urothelial Carcinoma

Kidney-Sparing Surgery for Upper Tract Urothelial Carcinoma-Modalities, Outcomes, and Limitations

Upper tract urothelial carcinoma (UTUC) accounts for 5-10% of urothelial cancers and is associated with high morbidity and mortality. Increasing incidence of UTUC has been observed since the 1970's, alongside the evolution of advance imaging techniques, precision biopsy equipment, and risk stratification models. The high morbidity of radical nephroureterectomy (RNU) which is still the gold-standard treatment for high-risk UTUC, has driven the development of kidney-sparing surgery alternatives for low-risk UTUC. Now, several treatment approaches have outcomes comparable to RNU for low-risk UTUC and guidelines are recommending kidney-sparing surgery for favorable low-risk disease. The main categories of kidney-sparing surgery include segmental ureterectomy, endoscopic ablation, chemoablation, and vascular-targeted phototherapy. These treatments are highly nuanced making them difficult to compare, but for most cases of favorable low-grade disease, we recommend endoscopic laser ablation with optional adjuvant intracavitary therapy. Adverse events associated with kidney-sparing surgery include ureteral stricture, bleeding requiring transfusion, and bladder recurrence of UTUC. Limitations of kidney-sparing surgery include appropriate tissue sampling (contributing to under-grading and under-staging), higher rates of ipsilateral recurrence, and potential for grade and stage progression. Collectively, these may subsequently necessitate RNU. Here, we review the technical variations and evidence behind kidney-sparing therapies as well as their practicality in the real world.

Efficacy of BCG for non-muscle invasive bladder cancer following nephroureterectomy for upper tract urothelial carcinoma

PURPOSE

To evaluate the efficacy of intravesical (IVe) Bacillus Calmette-Guerin (BCG) to treat non-muscle invasive bladder cancer (NMIBC) recurrences in patients who have previously undergone nephroureterectomy for upper tract urothelial carcinoma (UTUC).

METHODS

We performed a single institution retrospective review of patients who underwent nephroureterectomy for UTUC from 2009 to 2021. Patients who subsequently developed NMIBC treated with transurethral resection followed by IVe BCG were included in the study group. A control cohort was formed by retrospective review of patents with primary NMIBC treated with BCG during the same period. Patients in the control cohort were matched by stage of bladder cancer at a 2:1 ratio of control to study subjects. Demographic data, pathology of bladder tumors prior to and following BCG, use of maintenance BCG (mBCG), time to recurrence, time to progression, progression to cystectomy, and progression to metastatic disease were collected on all patients. Descriptive statistics were utilized to compare the 2 groups. The primary outcome was progression to muscle invasive disease. Secondary outcomes included intravesical recurrence free survival, disease free survival, and progression to metastatic disease. Univariable and multivariable logistic regression analysis was performed to elucidate independent variables associated with bladder tumor recurrence. Multivariable Cox regression analysis was used to assess the impact of prior UTUC on time to bladder tumor recurrence.

RESULTS

One-hundred and ninety-one patients underwent nephroureterectomy at our institution from 2009 to 2021 for UTUC. Twenty-five patients were identified to have subsequently developed NMIBC recurrences treated with inductions BCG. The control group was comprised of 50 patients with primary NMIBC matched by stage of bladder cancer for which BCG was indicated in the study group. Median (interquartile range [IQR]) follow-up was significantly longer in the control group relative to the study group (64.8 [50.1-85.6] vs 25 months [17-35]; P = 0.001). There were no significant differences in demographics between the study and control groups. The rate of progression to muscle invasive disease was 17% vs 0% in the study group and control group respectively (P = 0.0521). History of UTUC was associated with increased risk of intravesical bladder tumor recurrence post BCG on multivariable analysis (HR 2.5; P = 0.017) and Kaplan Meier survival analysis (P = 0.039). The mean time to bladder tumor recurrence after treatment with BCG was significantly worse in the study group at (7.9 vs. 23.9 months; P = 0.0322). Similarly, the rate of progression to metastatic disease was worse in the study group (24% vs 2%; P = 0.0047). Overall disease-free survival was also noted to be significantly worse on Kaplan Meier survival analysis in the study group (P = 0.0074). No statistically significant differences in the stage grade of bladder tumor recurrence, grade of bladder tumor recurrence, or rate of progression to cystectomy were identified.

CONCLUSIONS

Our study suggests reduced efficacy of BCG for NMIBC in patients with a history of UTUC. Patients in this population should be counseled accordingly. Research into alternative treatments for bladder tumor recurrence and more aggressive prophylactic regimens after nephroureterectomy for prevention of bladder tumor recurrence in this population is encouraged.

Variant histology is associated with more non-urothelial tract recurrence but less intravesical recurrence for upper tract urothelial carcinoma after radical nephroureterectomy

PURPOSE

To investigate the prognostic impact of variant histology (VH) on oncological outcomes in patients with upper urinary tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy (RNU).

PATIENTS AND METHODS

A total of 1239 patients with clinically localized UTUC who underwent RNU at a single institution between January 2005 and June 2020 were included. The VH was reviewed by a uro-pathologist at our institution. The Cox regression model was used to perform multivariate analysis, including VH and other established prognostic factors for post-RNU oncological outcomes (intravesical recurrence [IVR], non-urothelial recurrence, and cancer-specific death).

RESULTS

Of the 1239 patients with UTUC, 384 patients (31%) were found to have VH. Advanced tumor stage, lymph node metastasis, high tumor grade, lymphovascular invasion, open surgery, and renal pelvis had a significantly larger proportion of UTUC with VH compared to pure UTUC (all p < 0.05). VH was an independent prognostic factor associated with less IVR identified by multivariate analysis, more non-urothelial recurrence, and more cancer-specific mortality.

CONCLUSION

Patients with VH account for 31% with UTUC treated with RNU in this cohort. VH was an independent prognostic factor associated with more non-urothelial recurrence and cancer-specific mortality but less IVR.

Summary of the Clinical Practice Guidelines for Upper Tract Urothelial Carcinoma 2023 by the Japanese Urological Association

This article is an English translation of the Clinical Practice Guidelines for Upper Tract Urothelial Carcinoma (2nd edition) published in June 2023. The Japanese Urological Association's (JUA) Guidelines Committee on Upper Tract Urothelial Carcinoma (UTUC) created a 2023 update guideline to support clinicians' current evidence-based management of UTUC and to incorporate its recommendations into clinical practice. The new guideline adhered as closely as possible to the Minds Manual for Guideline Development 2020 ver. 3.0. Findings related to epidemiological, pathological, diagnosis, treatment, and follow-up were reviewed. In addition, seven clinical questions (CQs) were set to determine the grade of recommendation and level of evidence. Preconceptions and biases were removed from the preparation process, the overall evidence was evaluated appropriately, and recommendations were made after fully considering the balance between benefits and harms. Although the evidence is still insufficient to be taken up as a CQ, the latest important information is described in seven columns, and clinical issues that should be resolved in the future related to the CQ are described as recommendations for tomorrow. We hope that these guidelines will help medical professionals, patients, and their families involved in the treatment of UTUC in their decision-making, and hope that a critical review of these guidelines will lead to further refinements in the next edition.

A deep-learning workflow to predict upper tract urothelial carcinoma protein-based subtypes from H&E slides supporting the prioritization of patients for molecular testing

Upper tract urothelial carcinoma (UTUC) is a rare and aggressive, yet understudied, urothelial carcinoma (UC). The more frequent UC of the bladder comprises several molecular subtypes, associated with different targeted therapies and overlapping with protein-based subtypes. However, if and how these findings extend to UTUC remains unclear. Artificial intelligence-based approaches could help elucidate UTUC's biology and extend access to targeted treatments to a wider patient audience. Here, UTUC protein-based subtypes were identified, and a deep-learning (DL) workflow was developed to predict them directly from routine histopathological H&E slides. Protein-based subtypes in a retrospective cohort of 163 invasive tumors were assigned by hierarchical clustering of the immunohistochemical expression of three luminal (FOXA1, GATA3, and CK20) and three basal (CD44, CK5, and CK14) markers. Cluster analysis identified distinctive luminal (N = 80) and basal (N = 42) subtypes. The luminal subtype mostly included pushing, papillary tumors, whereas the basal subtype diffusely infiltrating, non-papillary tumors. DL model building relied on a transfer-learning approach by fine-tuning a pre-trained ResNet50. Classification performance was measured via three-fold repeated cross-validation. A mean area under the receiver operating characteristic curve of 0.83 (95% CI: 0.67-0.99), 0.8 (95% CI: 0.62-0.99), and 0.81 (95% CI: 0.65-0.96) was reached in the three repetitions. High-confidence DL-based predicted subtypes showed significant associations (p < 0.001) with morphological features, i.e. tumor type, histological subtypes, and infiltration type. Furthermore, a significant association was found with programmed cell death ligand 1 (PD-L1) combined positive score (p < 0.001) and FGFR3 mutational status (p = 0.002), with high-confidence basal predictions containing a higher proportion of PD-L1 positive samples and high-confidence luminal predictions a higher proportion of FGFR3-mutated samples. Testing of the DL model on an independent cohort highlighted the importance to accommodate histological subtypes. Taken together, our DL workflow can predict protein-based UTUC subtypes, associated with the presence of targetable alterations, directly from H&E slides.

Effectiveness and safety of immune checkpoint inhibitor monotherapy in advanced upper tract urothelial carcinoma: A multicenter, retrospective, real-world study

INTRODUCTION

The effectiveness and safety of immune checkpoint inhibitor (ICI) monotherapy in advanced upper tract urothelial carcinoma (UTUC) is less reported.

METHODS

In total, 106 consecutive advanced UTUC patients receiving ICI monotherapy were collected from nine high volume centers. Clinical outcomes were analyzed according to multiple parameters (e.g., treatment line, metastatic sites). Objective response rate (ORR), overall survival (OS) and progression-free survival (PFS) were captured after ICI initiation.

RESULTS

With a median follow-up of 12.0 months, 25 patients in the first-line group and 15 patients in the second-line group died of UTUC. We reported a median OS of 18.0 months, a median PFS of 5.0 months, and an ORR of 38.6% for patients in the first-line group; a median OS of 10.0 months, a median OS of 4.0 months, and an ORR of 27.8% for patients in the second-line group. Complete response was observed in two patients in the first-line group and one patient in the second-line group with a total complete response rate of 2.8%. In the univariate and multivariate analysis, visceral metastasis with a hazard ratio of 2.4 was associate with poor OS. The most common treatment-related adverse events included fatigue (11.3%), pruritus (10.4%), and diarrhea (6.6%).

CONCLUSIONS

This real-world study suggests that ICI monotherapy is active and has acceptable toxic effects for unresectable or metastatic UTUC as first-line therapy in cisplatin-ineligible patients or second-line therapy in platinum-refractory patients.

Genetic Interference of FGFR3 Impedes Invasion of Upper Tract Urothelial Carcinoma Cells by Alleviating RAS/MAPK Signal Activity

Upper tract urothelial cancer (UTUC) is a less common disease in Western countries but has a high level of prevalence in Asian populations. Compared to bladder cancer, unique etiologic and genomic factors are involved in UTUC. Fibroblast growth factor receptor 3 (FGFR3) up-regulation has been proposed as a promising target for bladder cancer therapy. In this study, we aimed to profile the expression of FGFR3 in Asian and Caucasian UTUC tissues and to evaluate the in vitro therapeutic efficacy of small interference RNA (siRNA)-mediated FGFR3 silencing in UTUC treatment. The FGFR3 expression levels in renal pelvis tissues and microarray sections from Asian and Caucasian patients with UTUC, respectively, were measured via immunohistochemistry. The BFTC-909 and UM-UC-14 UTUC cell lines were used to examine the effects of FGFR3 silencing on proliferation, migration, epithelial-mesenchymal transition (EMT) marker expression, and signaling machinery. FGFR3 expression increased as the TNM stage increased in both Asian and Caucasian UTUC tumors, and no statistical difference was identified between the two groups. In vitro studies demonstrated that FGFR3 siRNA delivery significantly inhibited proliferation and migration and suppressed the expression of EMT markers and transcription factors in UTUC cells. Mechanistically, FGFR3 silencing alleviated the constitutive expression of RAS and the phosphorylation of MAPK signaling mediators, including ERK1/2 and JNK1/2. FGFR3 silencing elicited an apoptosis-inducing effect similar to that of FGFR inhibition. Conclusion: siRNA-targeted FGFR3 expression may impede the expansion and invasion of UTUC cells by alleviating the RAS/MAPK signaling pathway. The genetic interference of FGFR3 expression via siRNA in UTUC cells may constitute a useful therapeutic strategy.

The impact of lymphovascular invasion in patients treated with radical nephroureterectomy for upper tract urothelial carcinoma: An extensive updated systematic review and meta-analysis

Patients with upper tract urothelial carcinoma (UTUC) often have a delayed diagnosis and by then, present with advanced disease which has been shown to be associated with lymphovascular invasion (LVI). It has been suggested to be involved in the metastatic cascade of the disease. In this review, we provide an extensive up-to-date summary of the current knowledge about the prognostic impact of LVI in patients undergoing radical nephroureterectomy (RNU). A systematic search of PubMed/MEDLINE, Scopus, EMBASE, and Web of Science for all reports published from 2010 through 2021 was performed. We performed pooled analyses of hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) of series that evaluated LVI as a prognostic factor in adults with UTUC who underwent RNU. The assessed oncological outcomes were disease recurrence, cancer-specific and overall survival. A meta-regression analysis was used to explore potential heterogeneity. A total of 58 series met the eligibility criteria for qualitative and quantitative synthesis. We included 29,829 patients, ranging from 101 to 2492 per study. All series were retrospective. LVI was present in 7,818 patients (26.2%). The median age of the patients was 69 years and the median follow-up was 40 months. In 40 of 58 studies (68.9%), adjuvant chemotherapy was given. The pooled HRs show that LVI predicts a greater risk of recurrence of the disease (pooled HR 1.43, 95% CI: 1.31-1.55, P = 0.000; I² = 76.3%), and decreases cancer-specific survival (pooled HR 1.53, 95% CI: 1.41-1.66, P = 0.000; I² = 72.3%) and overall survival (HR 1.56, 95% CI 1.45-1.69, P = 0.000; I² = 62.9%). It can be concluded that LVI is a common histologic pattern in surgical specimen in patients undergoing RNU for UTUC. LVI predicts a greater risk of recurrence and mortality, thus it should be carefully assessed in clinical practice to determine prognosis, and for optimal decision-making within the concept of personalized therapies.

Targeted therapies: Expanding the role of FGFR3 inhibition in urothelial carcinoma

The management of urothelial carcinoma (UC) has rapidly advanced in recent years with new approvals for immune checkpoint inhibitors and antibody-drug conjugates. However, while many UC tumors contain potentially actionable mutations, the role for targeted small molecule inhibitors has been limited. One such target is the fibroblast growth factor receptor (FGFR) family of proteins. Activating mutations and amplifications of FGFR3 are common in UC with higher incidences seen in upper tract as compared to lower tract disease. Consequently, multiple FGFR-directed targeted therapies have been developed and trialed in both UC and other solid tumors harboring FGFR mutations. At current, erdafitinib, an inhibitor of FGFR1-4, is the only approved targeted therapy in metastatic UC following the BLC2001 study, which demonstrated a 49% overall response rate in patients with UC harboring an FGFR3 mutation. Additional FGFR-directed agents also continue to be investigated across multiple disease stages in FGFR-mutated UC including infigratinib, rogaratinib, and AZD4547, among others. Ongoing trials are combining these agents with immune checkpoint inhibitors and chemotherapy regimens. The precision medicine revolution has begun in UC, and FGFR3 inhibitors are leading the charge toward a more personalized, biomarker-driven treatment paradigm.

The Predictive Value of Systemic Immune-Inflammation Index on Bladder Recurrence on Upper Tract Urothelial Carcinoma Outcomes after Radical Nephroureterectomy

BACKGROUND

This study aimed to assess the prognostic significance of pre-treatment lymphocyte-related systemic inflammatory biomarkers in upper tract urothelial carcinoma (UTUC) patients.

METHODS

This study included non-metastatic UTUC patients treated at our hospital between 2001 and 2013. The receiver operating characteristic curve was used to obtain the optimal neutrophile-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII). Multivariate logistic regression was performed to investigate the relationship between NLR, PLR, and SII and clinical pathologic characteristics. The Kaplan-Meier method was used to calculate the metastasis-free survival (MFS), cancer-specific survival (CSS), and bladder recurrence-free survival (BRFS), and the log-rank test was used to compare the survival rate.

RESULTS

Overall, 376 patients were included in the current study. An elevated SII was associated with symptomatic hydronephrosis, bladder cancer history, advanced pathologic tumor stage, lymph node invasion, adjuvant chemotherapy and concomitant carcinoma in situ (CIS); high NLR was associated with older age, symptomatic hydronephrosis, hemodialysis status, anemia, multifocal tumor, advanced pathologic tumor stage, and adjuvant chemotherapy; and high PLR was associated with older age, anemia, advanced pathologic tumor stage, and adjuvant chemotherapy. The Kaplan-Meier analysis indicated that patients exhibiting higher NLR, PLR, and SII showed significantly poor MFS and CSS rates. Only high SII showed significantly worse BRFS rates.

CONCLUSIONS

The NLR, PLR, and SII were independent predictive factors for both MFS and CSS in UTUC patients. Among the factors, only elevated SII can predict bladder recurrence. Therefore, the patients might need close bladder monitoring during the follow-up.

Expression Analysis and Mutational Status of Histone Methyltransferase KMT2D at Different Upper Tract Urothelial Carcinoma Locations

The gene coding for histone methyltransferase KMT2D is found among the top mutated genes in upper tract urothelial carcinoma (UTUC); however, there is a lack of data regarding its association with clinicopathologic features as well as survival outcomes. Therefore, we aimed to investigate KMT2D expression, mutation patterns, and their utility as prognostic biomarkers in patients with UTUC. A single-center study was conducted on tumor specimens from 51 patients treated with radical nephroureterectomy (RNU). Analysis of KMT2D protein expression was performed using immunohistochemistry (IHC). Customized next-generation sequencing (NGS) was used to assess alterations in KMT2D exons. Cox regression was used to assess the relationship of KMT2D protein expression and mutational status with survival outcomes. KMT2D expression was increased in patients with a previous history of bladder cancer (25% vs. 0%, p = 0.02). The NGS analysis of KMT2D exons in 27 UTUC tumors revealed a significant association between pathogenic KMT2D variants and tumor location (p = 0.02). Pathogenic KMT2D variants were predominantly found in patients with non-pelvic or multifocal tumors (60% vs. 14%), while the majority of patients with a pelvic tumor location (81% vs. 20%) did not harbor pathogenic KMT2D alterations. Both IHC and NGS analyses of KMT2D failed to detect a statistically significant association between KMT2D protein or KMT2D gene alteration status and clinical variables such as stage/grade of the disease or survival outcomes (all p > 0.05). KMT2D alterations and protein expression were associated with UTUC features such as multifocality, ureteral location, and previous bladder cancer. While KMT2D protein expression and KMT2D mutational status do not seem to have prognostic value in UTUC, they appear to add information to improve clinical decision-making regarding the type of therapy.