Urothelial Carcinoma Histology Research Articles

Abstract PR002: Sarcomatoid Histological Variants of Canine Muscle-Invasive Bladder Cancer: Transcription Factor Activation Highlights Pathways of Epithelial-Mesenchymal Transformation Similar to Humans

Abstract The histologic heterogeneity of human Muscle Invasive Bladder Cancer (MIBC) is one of the main contributing factors to poor treatment outcomes. Recent reports on MIBC histological variants have highlighted increased levels of transcription factors (TF) associated with epithelial-mesenchymal transformation (EMT) and epigenetic regulation in the sarcomatoid histology variant of MIBC. Dogs with spontaneously developing MIBC have been shown to display similar histological and molecular features, in addition to closely mimicking the clinical behavior of human MIBC. Here, we add to previously reported data on histological variants in canine MIBC by evaluating 21 tumor biopsies for variant histology and performing bulk RNAseq analyses on 3 organoid cell lines derived from one sarcomatoid subvariant and two conventional urothelial carcinoma (UC). MIBC biopsies from 21 dogs were reviewed for variant histology by a human urologic pathologist. Organoids derived from the urine of canine MIBC patients were cultured, preserved in RNA later, and sequenced for mRNA expression to identify TF associated with sarcomatoid variants versus conventional UC. All canine MIBC biopsies were classified as invasive, high-grade UC. Histologic variants were identified as glandular differentiation in 7/21, sarcomatoid differentiation in 3/21, squamous differentiation in 3/21, micropapillary carcinoma in 1/21 MIBC samples and small nested variants in 1/21 samples; with the rest of the tumors classified as conventional UC. Raw RNAseq analyses revealed no clear clustering of expression profiles between the three organoid cell lines, indicating distinct RNA expression profiles between the sarcomatoid variants and conventional UC of canine MIBC. To evaluate differences in the expression of TF targets between the organoid cell lines, pathway analyses and VIPER algorithms were used. Organoids derived from sarcomatoid variant UC showed increased expression of Snail familiy transcription repressor 1 (SNAI1) along with decreased expression of cadherin 1 (CDH1), indicating a signature of EMT, similar to that previously identified in human MIBC organoids with sarcomatoid variant histology. Canine MIBC organoids derived from conventional UC histology samples showed a TF profile associated with proliferation, metastasis, and progression, such as increased Zinc finger E-box binding homeobox 1 (ZEB1), E2F transcription factor 3 (E2F3), and centromere protein F (CENPF), as previously described in humans with high grade, invasive UC. In conclusion, the frequency of some histologic variants in canine MIBC, such as sarcomatoid UC, appear to be higher than reported in human patients. TF analyses of canine MIBC-derived organoid cell lines showed evidence of EMT, similar to the sarcomatoid variants of MIBC in humans. Organoids derived from canine MIBC could potentially serve as a valuable model for evaluating the efficacy of novel treatment modalities for the rare histologic variants of UC. Citation Format: Karin Allenspach, Mohamed Elbadawy, Hannah Nocholson, Christopher Zdyrski, John Cheville, Eugene Douglass, Elizabeth W. Howerth, Lilian Oliveira, Jonathan P. Mochel. Sarcomatoid Histological Variants of Canine Muscle-Invasive Bladder Cancer: Transcription Factor Activation Highlights Pathways of Epithelial-Mesenchymal Transformation Similar to Humans [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr PR002.

Neutralizing GDF-15 in muscle-invasive bladder cancer (MIBC): A neoadjuvant immunotherapy trial of visugromab (CTL-002) in combination with the anti-PD1 antibody nivolumab (GDFather-Neo).

TPS712 Background: Neoadjuvant chemotherapy (NACT) is a well-established treatment modality in MIBC but suffers from limited activity and significant toxicity. Neoadjuvant immunotherapy (I/O) demonstrated clinical safety and efficacy in various solid tumors including MIBC, with potentially less toxicity. Results from previous studies of single-agent I/O indicated a proportion of pathologic complete responses (ypT0N0) similar to that reported with NACT. Therefore, improving ypT0N0 responses remains a major task for treatment of MIBC. Increasing evidence emerged that Growth and Differentiation Factor 15 (GDF-15) plays a critical local immunosuppressive role. Apart from blocking immune-cell entry into tissues GDF-15 also has major impact on the formation of the immune synapse. Many tumors overexpress GDF-15 and have hijacked this mechanism to block I/O therapy success. Various translational research efforts indicated that GDF-15 may play a significant role for immunosuppression and T-cell exclusion in urothelial carcinoma (UC). Visugromab (CTL-002) is a GDF-15 neutralizing IgG4 monoclonal antibody that demonstrated in Phase 1 a favorable safety profile and promising clinical activity with durable and deep responses in PD-1/PD-L1 relapsed/refractory metastatic solid tumors in combination with the anti-PD1 antibody Nivolumab (Nivo)*. The Neo-GDFather trial is intended to investigate the combination of Visugromab with Nivo vs. Nivo monotherapy as neoadjuvant therapy for MIBC in patients (pts) who are ineligible for or elect not to undergo NACT. Primary endpoints are the complete pathologic response rate and radiologic response. Methods: Multi-center, parallel-cohorts and single-blinded Phase 2 study of neoadjuvant therapy in pts planned for radical cystectomy (RC). A total number of 30 subjects with stage T2-T4N0M0 MIBC will be enrolled and assigned 1:1 to receive either Nivo + Visugromab or Nivo + Placebo after stratification for CPS PD-L1 expression and cT-stage. Other inclusion criteria comprise an ECOG performance status 0-1 and a pure/predominant UC histology. No statistical assumptions were undertaken at this stage.Treatment consists of three 4-week cycles [i.v., Q4Wk], and RC is planned 4-8 weeks after last dose of study drug. After RC, pts will follow standard recommendations of EAU guidelines. Primary endpoints are the proportion of ypT0N0 response and radiologic response rate. Secondary endpoints comprise additional efficacy parameter, surgical and medical safety, PK and PD assessments. Translational research includes evaluation of immunologic parameters in the tumor, other immune-correlates and molecular profiles, as well as evaluation of treatment-emergent cytokine and chemokine profiles in peripheral blood. * Melero et al., #2501 ASCO Annual Meeting 2023 Oral Abstract Session. Clinical trial information: Not yet available.

Clinical Outcomes of Patients With Variant Histology of Urothelial Carcinoma After Radical Cystectomy

Purpose: The efficacy of standard chemotherapy or radical cystectomy in patients who have urothelial tumors with variant histology (VH) is very limited in terms of their prognosis. This study aimed to investigate the prognosis of bladder cancer (BC) patients with VH who underwent radical cystectomy (RC).Materials and Methods: We retrospectively evaluated 327 BC patients who underwent RC at Pusan National University Yangsan Hospital between February 2010 and June 2021. VH was categorized into less and more aggressive types according to the patient’s mortality risk relative to pure urothelial carcinoma (PUC). More aggressive types included micropapillary, plasmacytoid, and sarcomatoid variants. Less aggressive types comprised other variant types, including squamous differentiation, glandular differentiation, lipoid, and nested. Small cell carcinoma, pure adenocarcinoma, pure squamous cell carcinoma, and lymphoma BC were excluded from analysis. The progression-free survival (PFS) and overall survival (OS) rates were evaluated using Kaplan-Meier analysis and Cox regression.Results: After the exclusion of nonurothelial tumors, data from 299 patients were available for analysis. We identified 244 (74.6%) and 55 patients (16.8%) with PUC and urothelial carcinoma with VH, respectively. VH patients were categorized as having less aggressive (n=35) and more aggressive (n=20) types. Univariate analysis identified significant differences in PFS (p=0.031) between patients with PUC (n=244) and more aggressive VH (n=20). Multivariate analysis showed that more aggressive VH was significantly associated with OS and PFS. In the Kaplan-Meier analysis, a statistically significant difference was observed between PUC and more aggressive VH in OS and PFS.Conclusions: VH patients with more aggressive types showed more advanced TNM stages at presentation than PUC patients. Pathological upstaging after RC was more common in VH patients. Among VH patients, the presence of a more aggressive VH type can be an independent predictor of progression after RC, with a worse prognosis than that of PUC patients.

Radiotherapy vs. Cystectomy for Treatment of Muscle Invasive Bladder Cancer in Very Elderly Patients

Radical cystectomy (RC) has long remained the principal treatment of muscle invasive bladder cancer (MIBC). It is, however, associated with significant morbidity, long recovery, and reported worse overall and cancer specific survival, particularly for the very elderly (age > = 80). Bladder preservation with transurethral resection of bladder tumor (TURBT) followed by radiotherapy (RT) +/- concurrent chemotherapy (ChT) is regarded as a curative-intent alternative to RC in well-selected patients. The optimal treatment strategy remains unclear in very elderly patients. We hypothesize that outcomes following RT vs RC are clinically equivalent for treatment of MIBC in very elderly patients. Patients > = 80 years old with T2-T4 N0-N1 bladder cancer treated definitively with RT versus RC were included. Exclusion criteria included history of pelvic RT, prior cystectomy, or palliative treatment intent. Clinicopathologic and treatment-related details, as well as clinical outcomes and toxicities were retrospectively abstracted. Kaplan-Meier analyses were performed. At a median follow-up of 17 months (range 0.25-190), 47 patients received RT vs 83 patients who underwent RC with median age of 86 years (80-97) vs 83 years (range 80-91) (p<0.01), respectively. Median Charlson Comorbidity Index was similar between groups (p = 0.35) with median 7 for both cohorts, predicting 0% estimated 10y survival. Most patients had cT2 tumors (91% vs 99%, p = 0.06), cN0 nodal status (96% vs 100%, p = 0.06), and urothelial carcinoma histology (79% vs 90%, p = 0.22). Most RT patients received concurrent ChT (90%) and a minority of RC patients received neoadjuvant ChT (16%). 70% of RT pts had complete TURBTs prior to RT. Common RT regimens were 50-55 Gy in 20-25 fractions or 60-64.8 Gy in 30-36 fractions, using IMRT (89%) or 3D conformal (11%) technique. Overall survival for RT vs RC at 1- and 2- years was 79% vs 85% and 57% and 69%, respectively (p = 0.20). Locoregional control at 1- and 2-years was 73% vs 70% and 63% vs 66% (p = 0.59), respectively. Progression free survival at 1- and 2-years was 69% vs 66% and 52% vs 54% (p = 0.75), respectively. No RT patients went on to receive salvage cystectomy. Treatment complications are listed in Table 1; the Clavien Dindo classification system was used to describe acute surgical complications of RC and the Common Terminology Criteria for Adverse Events (CTCAE) Dictionary v5.0 was used for acute and late toxicity of RT. In the very elderly, RT (with or without concurrent ChT) offers survival and locoregional control rates comparable to RC, with a favorable side effect profile. RT should be offered for definitive management of non-metastatic MIBC as an alternative to RC in selected, well- informed, and compliant very elderly patients.

The Impact of Variant Histology in Patients with Urothelial Carcinoma Treated with Radical Cystectomy: Can We Predict the Presence of Variant Histology?

Considering the divergent biological behaviors of certain histological subtypes of urothelial carcinoma, it would be of great importance to examine the impact of variant histology and to predict its presence in patients with bladder cancer. A single-center cohort study included 459 patients who underwent radical cystectomy for urothelial carcinoma between 2017 and 2021. Patients were followed up with until July 2022. We compared clinical, laboratory, and histopathologic characteristics and the overall survival between patients with pure urothelial carcinoma and variant histologies. Our results showed that the patients with variant histology were older and preoperatively more frequently had hydronephrosis and higher values of leukocytes and neutrophils. Also, we found a significant association between variant histology and an advanced stage of tumor disease, the presence of lymphovascular invasion, positive surgical margins, and metastases in surgically resected lymph nodes. The number of neutrophils was identified as an independent preoperative predictor of the presence of variant histology after a radical cystectomy. The overall survival of the patients with variant histology was significantly lower compared to the patients with pure urothelial carcinoma. According to our results, the presence of variant histology represents a more aggressive form of the disease. Preoperative neutrophil counts may indicate the presence of variant histology of urothelial carcinoma in patients with bladder cancer.

Impact of histology on the efficacy and safety of pembrolizumab (pembro) monotherapy for advanced urothelial carcinoma (UC) in the phase 3 KEYNOTE-045 and KEYNOTE-361 trials.

4512 Background: For patients (pts) with advanced UC, pembro monotherapy has shown antitumor activity as first-line (1L) therapy in the phase 3 KEYNOTE-361 (NCT02853305) study of pembro ± platinum-based chemotherapy (chemo) vs platinum-based chemo and as second-line therapy in the phase 3 KEYNOTE-045 (NCT02256436) study of pembro vs investigator’s choice chemo. This exploratory analysis evaluated efficacy and safety of pembro monotherapy by UC histology in KEYNOTE-361 and KEYNOTE-045. Methods: KEYNOTE-361 enrolled pts with advanced UC and no prior systemic therapy; KEYNOTE-045 enrolled pts with advanced UC whose disease progressed or relapsed after 1L platinum-based chemo. Pure transitional cell (TC) and mixed predominant TC histology, as assessed by investigator, were allowed. Pembro monotherapy was given at a dose of 200 mg IV Q3W for up to 2 y or until disease progression, unacceptable toxicity, or withdrawal of consent in both studies. End points for this exploratory analysis were ORR, DOR, and PFS per RECIST v1.1 by central radiology assessment, and OS and safety in pts with pure TC or mixed predominant TC allocated to receive pembro monotherapy. Results: A total of 307 randomly assigned pts (280 [91.2%] pure TC histology; 27 [8.8%] mixed predominant TC histology) from KEYNOTE-361 and 268 pts (186 [69.4%] pure TC histology; 82 [30.6%] mixed predominant TC histology) from KEYNOTE-045 were included. Median follow-up for both studies was ≥32 mo. PFS, ORR, DOR, and OS for pembro were generally similar in pts with mixed predominant TC histology and pts with pure TC histology. In treated pts, grade 3-5 treatment-related AEs occurred at similar rates in KEYNOTE-361 (17.3% [48/277] pure TC; 18.5% [5/27] mixed predominant TC) and KEYNOTE-045 (16.9% [31/183] pure TC; 17.3% [14/81] mixed predominant TC). Conclusions: The observed clinical activity and safety profile of pembro monotherapy was generally consistent irrespective of histology in pts with UC in the KEYNOTE-361 and KEYNOTE-045 studies. Small sample size in some subgroups and limited data available to classify histology subgroups were limitations of this exploratory analysis. Clinical trial information: NCT02256436; NCT02853305 . [Table: see text]

PD09-02 THE IMPACT OF VARIANT HISTOLOGY ON CLINICAL OUTCOMES AFTER RADIATION-BASED THERAPY FOR MUSCLE-INVASIVE BLADDER CANCER

You have accessJournal of UrologyCME1 Apr 2023PD09-02 THE IMPACT OF VARIANT HISTOLOGY ON CLINICAL OUTCOMES AFTER RADIATION-BASED THERAPY FOR MUSCLE-INVASIVE BLADDER CANCER Daniel Halstuch, Ronald Kool, Gautier Marcq, Rodney H Breau, Peter C Black, Bobby Shayegan, Michael Kim, Ionut Busca, Hamidreza Abdi, Mark T. Dawidek, Michael Uy, Gagan Fervaha, Fabio L. Cury, Nimira S. Alimohamed, Claudio Jeldres, Ricardo Rendon, D. Robert Siemens, Girish S. Kulkarni, Wassim Kassouf, and Jonathan I. Izawa Daniel HalstuchDaniel Halstuch More articles by this author , Ronald KoolRonald Kool More articles by this author , Gautier MarcqGautier Marcq More articles by this author , Rodney H BreauRodney H Breau More articles by this author , Peter C BlackPeter C Black More articles by this author , Bobby ShayeganBobby Shayegan More articles by this author , Michael KimMichael Kim More articles by this author , Ionut BuscaIonut Busca More articles by this author , Hamidreza AbdiHamidreza Abdi More articles by this author , Mark T. DawidekMark T. Dawidek More articles by this author , Michael UyMichael Uy More articles by this author , Gagan FervahaGagan Fervaha More articles by this author , Fabio L. CuryFabio L. Cury More articles by this author , Nimira S. AlimohamedNimira S. Alimohamed More articles by this author , Claudio JeldresClaudio Jeldres More articles by this author , Ricardo RendonRicardo Rendon More articles by this author , D. Robert SiemensD. Robert Siemens More articles by this author , Girish S. KulkarniGirish S. Kulkarni More articles by this author , Wassim KassoufWassim Kassouf More articles by this author , and Jonathan I. IzawaJonathan I. Izawa More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003240.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Radiation-based therapy (RT) is an acceptable bladder-preserving treatment for selected patients with muscle-invasive bladder cancer (MIBC). Real-world outcomes of RT-based therapy for histologic variants are lacking. Our objective was to compare oncological outcomes between pure urothelial carcinoma (PUC) and variant urothelial carcinoma (UC-HV) patients with MIBC treated with RT-based therapy. METHODS: A collaborative Canadian multicenter retrospective study of 864 patients with MIBC who underwent curative-intent bladder-sparing RT for T2-4a N0-3 M0 MIBC between 2001-2018. Tumours were classified based on the presence of non-urothelial components as either PUC or UC-HV. A complete response (CR) was defined by a negative tumour bed biopsy and/or the combination of a negative urine cytology, negative cystoscopy and normal imaging post-RT. Loco-regional disease-free survival (LR-DFS), disease-free survival (DFS), metastasis-free survival (MFS), cancer-specific survival (CSS) and overall survival (OS) were calculated using Kaplan-Meier method. Cox regression models were used to estimate the effect of UC-VH on oncologic outcomes for patients with MIBC treated with RT-based therapy. RESULTS: Of 864 patients treated with RT-based therapy, 123 (14.2%) had UC-HV. Seventy-five (61%) had UC-HV with squamous and/or glandular differentiation and 48 (39%) had other variants. A CR after RT-based therapy was confirmed in 69.1% of patients with PUC and 63.4% with UC-HV (p=0.266). The 5-yr CSS was 62.0% in PUC vs. 66.8% in UC-HV. The 5-yr OS was 47.7% in PUC and 53.3% in UC-HV. Rates of LR-DFS, DFS and MFS at 5 years were not statistically different between the groups. Salvage cystectomy (sRC) rates were similar (p=0.781). In the univariate Cox regression analyses, UC-HV status was not associated with inferior LR-DFS, DFS, MFS, CSS, and OS. CONCLUSIONS: Variant histology of urothelial carcinoma responded to RT-based therapy with no significant difference in CR, LR-DFS, DFS, MFS, CSS, OS, or rates of salvage cystectomy compared to PUC. The presence of variant histology in MIBC does not confer resistance to RT-based therapy and these patients should not be excluded from bladder preservation treatment. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e239 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Daniel Halstuch More articles by this author Ronald Kool More articles by this author Gautier Marcq More articles by this author Rodney H Breau More articles by this author Peter C Black More articles by this author Bobby Shayegan More articles by this author Michael Kim More articles by this author Ionut Busca More articles by this author Hamidreza Abdi More articles by this author Mark T. Dawidek More articles by this author Michael Uy More articles by this author Gagan Fervaha More articles by this author Fabio L. Cury More articles by this author Nimira S. Alimohamed More articles by this author Claudio Jeldres More articles by this author Ricardo Rendon More articles by this author D. Robert Siemens More articles by this author Girish S. Kulkarni More articles by this author Wassim Kassouf More articles by this author Jonathan I. Izawa More articles by this author Expand All Advertisement PDF downloadLoading ...

MP56-19 MACHINE LEARNING FRAMEWORK-BASED PROGNOSTIC CLASSIFIER FOR PREDICTING RECURRENCE-FREE SURVIVAL IN PATIENTS UNDERGOING RADICAL CYSTECTOMY FOR UROTHELIAL BLADDER CANCER

You have accessJournal of UrologyCME1 Apr 2023MP56-19 MACHINE LEARNING FRAMEWORK-BASED PROGNOSTIC CLASSIFIER FOR PREDICTING RECURRENCE-FREE SURVIVAL IN PATIENTS UNDERGOING RADICAL CYSTECTOMY FOR UROTHELIAL BLADDER CANCER Giovanni Cacciamani, Yifan Xue, Udu Durairaj, Sidney Roberts, Dhruv Patel, Ragheb Raad, Gus Miranda, Sarmad Sadeghi, Andrew Hung, Inderbir Gill, Mihir Desai, Peter Kuhn, Jeremy Mason, and Assad Oberai Giovanni CacciamaniGiovanni Cacciamani More articles by this author , Yifan XueYifan Xue More articles by this author , Udu DurairajUdu Durairaj More articles by this author , Sidney RobertsSidney Roberts More articles by this author , Dhruv PatelDhruv Patel More articles by this author , Ragheb RaadRagheb Raad More articles by this author , Gus MirandaGus Miranda More articles by this author , Sarmad SadeghiSarmad Sadeghi More articles by this author , Andrew HungAndrew Hung More articles by this author , Inderbir GillInderbir Gill More articles by this author , Mihir DesaiMihir Desai More articles by this author , Peter KuhnPeter Kuhn More articles by this author , Jeremy MasonJeremy Mason More articles by this author , and Assad OberaiAssad Oberai More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003309.19AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: To assess the potential value of using machine learning (ML) approaches to derive risk prediction models for urothelial bladder cancer (BCa) recurrence at 1, 3, and 5 years after radical cystectomy (RC). METHODS: We used our established, IRB-approved (HS-01B014), longitudinally maintained, RC database of consecutive BCa primary surgical cases containing prospectively collected, detailed clinical, radiologic, and pathologic elements (years 1975-2016) to select patients with urothelial BCa. We included on only those with urothelial carcinoma histology treated with intent to cure. We excluded non-BCa primary patients undergoing RC for other pelvic malignancies. We further sub-divided the data into three groups with known recurrence-free survival (RFS) status at the 1-, 3-, and 5-year marks from the time of RC. The data was split into training (60%), validation (20%) and testing sets (20%). Separate classifiers for predicting 1-, 3-, and 5-year RFS were constructed using ML methods that included support vector machines, multilayer perceptrons, random forests (RFC), gradient boosting (GBC), extra trees (ExTC), and AdaBoost. RESULTS: Our analysis included 2152 patients with uBCa in our dataset, of which we have a minimum of 1 year of continuous data. The performance of the three top models in predicting 1-, 3-, and 5-year RFS is 0.882, 0.830, and 0.876 for RFC, 0.884, 0.849, and 0.874 for ExtC, and 0878, 0.828, and 0.872 for GBC, respectively. The AUC for the set of the top 12 features showed an accuracy between 0.827(95% CI 0.826-0.827) to 0.879 (95% CI 0.877-0.880). CONCLUSIONS: We report a ML-based framework, which incorporates disease and patient factors to predict 1, 3, and 5 years of RFS in patients undergoing RC for BCa with higher accuracy than the leading nomograms. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e782 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Giovanni Cacciamani More articles by this author Yifan Xue More articles by this author Udu Durairaj More articles by this author Sidney Roberts More articles by this author Dhruv Patel More articles by this author Ragheb Raad More articles by this author Gus Miranda More articles by this author Sarmad Sadeghi More articles by this author Andrew Hung More articles by this author Inderbir Gill More articles by this author Mihir Desai More articles by this author Peter Kuhn More articles by this author Jeremy Mason More articles by this author Assad Oberai More articles by this author Expand All Advertisement PDF downloadLoading ...

Genomic landscape of locally advanced or metastatic urothelial carcinoma with squamous differentiation compared to pure urothelial carcinoma.

Urothelial carcinoma with squamous differentiation (UCS) is the most common variant differentiation of urothelial carcinoma (UC). Although treatment is usually similar to pure UC, there is paucity of data regarding its genomic landscape and putative molecular drivers. In this study, we compared the mutational profile of tumors with UCS and UC histology. In this IRB-approved retrospective study, patients with advanced UCS and UC undergoing tumor based comprehensive genomic profiling from a CLIA-certified laboratory were included. An independent genitourinary pathologist reviewed all cases. Patients were determined to have UCS based on presence of any component of squamous differentiation. Patients with UC having any other secondary histology variant were excluded. Genes with alterations (GA) in less than 5% of patients and variants of unknown significance were excluded from the analysis. Chi-square test was used to compare gene aberration frequency and the p-values were adjusted for false using Benjamini-Hochberg (BH) correction. Among the 87 eligible patients with UCS (n=31) and UC (n=56), patients with UCS were more likely to be female (32.3% vs. 14.3%, p=0.047) with no significant differences in other clinicopathological features. Most common genomic alterations seen in UCS were TP53 (67.7%), KMT2D (48.4%) and ARID1A (32.3%). KMT2D mutations were significantly enriched in UCS (48.4% vs. 0%, FDR adj p <0.001, p = <0.001) compared to UC. Prevalence of CUL4A mutations was numerically higher in UCS vs. UC (12.9% vs. 1.8%, FDR adj p = 0.43, p = 0.03). Tumor mutation burden and the number of genomic aberrations per patient were not significantly different between the two groups. These findings highlight significant enrichment of KMT2D mutations in UCS and potential role of chromatin remodeling genes as drivers and potential therapeutic targets.

Evaluation of the Extent of Variant Histology in Urothelial Carcinoma as a Predictive Marker of Clinical Outcomes After Radical Cystectomy.

This study investigated the impact of the extent of variant histology (VH) on the prognosis of patients with bladder cancer (BC). We retrospectively evaluated consecutive patients with muscle-invasive BC who were treated with radical cystectomy (RC) at our institution between 2005 and 2018. Recurrence-free survival (RFS) and overall survival (OS) rates were evaluated using Kaplan-Meier analysis and Cox regression. We identified 103 and 47 patients with pure urothelial carcinoma (UC) and a VH in UC, respectively. At the cutoff of 80%, univariate analysis identified significant differences in RFS (p=0.046) and OS (p=0.038) between patients with ≥80% VH (n=21) and those with <80% VH (n=26). Multivariate analysis revealed that the presence of ≥80% VH was significantly associated with RFS and OS. The presence of ≥80% VH in UC could be an independent predictor of recurrence and mortality after RC.

Molecular Profiling of Metastatic Bladder Cancer Early-Phase Clinical Trial Participants Predicts Patient Outcomes.

Prognosis for patients with metastatic bladder carcinoma (mBC) remains limited and in need of novel therapies. We retrospectively analyzed medical records of 43 patients with platinum-refractory metastatic bladder cancer (mBC) who participated in one or more phase I trials of various investigational therapies. Patients' tumors or circulating tumor DNA were analyzed by next-generation sequencing. The median progression-free survival was 4.2 months, the median overall survival was 9.6 months, and the overall response rate was 17.5%. TP53, ERBB2, PI3KCA, FGFR3, and ARID1A alterations were detected in 66%, 29%, 27%, 24%, and 22% of all patients, respectively. Alterations in FGFR3 were almost mutually exclusive of TP53. More than half (64%) of patients with an FGFR alt received an FGFR inhibitor, 67% of which achieved disease control. Among patients with urothelial carcinoma histology, those harboring a TP53 alteration had a shorter median progression-free survival (PFS) compared with those whose tumors carry wild-type TP53. The reverse relationship was observed in patients harboring an FGFR alteration. IMPLICATIONS: Patients with platinum-refractory mBC derive clinical benefit from participating in early-phase clinical trials and their survival outcomes correlate with the genetic profile of the tumor. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/19/3/395/F1.large.jpg.

Genomic landscape of variant urinary tumor histologies.

467 Background: The genetics of urothelial carcinoma (UC), the most common histology of urinary tract (UT) tumors, is well characterized; much less is known about the genomic features of rare histologic variants of UT tumors. We aim to compare the genomic alterations (GA) of UT tumors with adenocarcinoma (AD), small cell (SC), squamous cell (SQ), or plasmacytoid (PC) histologies, to UC tumors. Methods: We identified patients with pure variant (AD, SC, SQ, PC) or UC histology with genetic characterization through the GENIE registry. Patient tumor genomic data were captured by Memorial Sloan Kettering Cancer Center (MSK)-IMPACT and Dana-Farber Cancer Institute (DFCI)-Oncopanel NGS initiatives. Tumors with mixed histology were excluded. We limited our analysis to genes tested &gt;1000 times (N=211). Mutation frequencies and copy number variants (CNVs), collectively called GAs, were determined for AD, SC, SQ, PC, and UC, and were compared using the Fisher’s Exact test and Kruskall Wallis test. Nominal p values were obtained, and FDR correction was employed (q &lt; 0.1). Results: We identified 1199 patients with available genomic data who met the inclusion criteria. Histologic distribution was: 32 AD, 13 SC, 15 SQ, 11 PC, and 1128 UC tumors. The median age was 68 years and 77% of patients were male. Statistically significant differences in genetic alterations by subtype are shown in the table below. ARID1A and KDM6A GAs were higher in UC; PC and SC; CDH1 GAs higher in PC; RB1 and TP53 GAs higher in SC; SMAD4 GAs higher in AD; and NFE2L2 GAs higher in SQ. Conclusions: Variant UT histologies exhibit a distinct pattern of alterations compared to UC, consistent with their divergent clinical behavior. This suggests different biological origins for these variant histologies and possibly different therapeutic vulnerabilities. Exploring the GAs of these UT tumors in larger datasets is warranted. [Table: see text]

The optimal management of variant histology in muscle invasive bladder cancer.

Bladder cancer is a heterogenous disease that is associated with tangible mortality in muscle invasive disease. The WHO 2016 classification of urothelial tumours reflects the contemporary approach towards histological variants in bladder cancer, including variants of urothelial carcinoma (UC) and non-urothelial variants. This review focuses on variant histology in UC, and discusses the importance of accurate histological diagnosis, and subsequent risk stratification and therapeutic decision making based on proper variant recognition. Most urothelial variants are associated with poorer outcomes compared to conventional UC, although some perform reasonably better. However, high quality evidence detailing optimal treatment and survival outcomes are still lacking in literature, due to the rarity of these cases.

Prognostic value of pretreatment inflammatory markers in variant histologies of the bladder: is inflammation linked to survival after radical cystectomy?

To investigate differences in standard preoperative inflammatory markers in patients with urothelial carcinoma (UC) and variant histologies undergoing radical cystectomy (RC) and determine its impact on survival. Patients undergoing RC at an academic high-volume center were retrospectively analyzed. Preoperatively taken CRP, leukocytes, hemoglobin (Hb), and thrombocytes were analyzed as routine inflammatory biomarkers. Log-rank tests and Kruskal-Wallis analysis were used to calculate for differences in survival and in blood levels of biomarkers. 886 patients with complete follow-up and UC or variant histology underwent RC at our institution between 2004 and 2019. Although variant histology presents with significantly higher t stage than UC, cancer-specific survival (CSS) of UC (1-year-CSS: 93%) is not significantly different to variant histology of UC with squamous differentiation (UCSD, 1-year-CSS: 81%), squamous cell carcinoma (SCC, 1-year-CSS: 82%), and adenocarcinoma (AC, 1-year-CSS: 81%). In UC, alterations in all biomarkers except leukocytes beyond routine cut-off values were associated with poor survival (p < 0.01), whereas Hb beyond cut-off values are associated with poor prognosis in SCC (p < 0.05). CRP levels are significantly elevated in UCSD and SCC at time of surgery compared to UC (p < 0.05). Inflammatory biomarkers reveal distinctive patterns across UC and variant histologies of bladder cancer. As inflammation might play an important role in cancer progression, further research is warranted to understand those molecular mechanisms and their potential therapeutic impact in variant histology of bladder cancer.

Abstract CT187: Pembrolizumab and nanoparticle albumin bound paclitaxel (nab-paclitaxel) as salvage therapy for metastatic urothelial carcinoma (UC)

Abstract Methods: In an open-label, single-arm, phase 2 trial, pts receive pembro 200 mg intravenously (IV) on D1 and 125 mg/m2 IV nPtx on D1 and D8, every 3 weeks, until disease progression (PD) or onset of unacceptable toxicity. Key inclusion criteria are: predominant UC histology, failure of ≤2 platinum-based CT for metastatic disease. Response is evaluated by RECIST v.1.1 criteria every 2 cycles. Biomarkers include PD-L1 expression with the combined positive score (CPS) and comprehensive genomic profiling on tumor and blood samples (FoundationONE and FoundationACT assay). The primary endpoint of the study is the progression-free survival (PFS). The target is to detect an improvement in the median PFS from ≤3.0 months (H0) to ≥5.0 months (H1). Results: Between 01 and 12/2019, PEANUT study enrolled 63 pts evaluable for the study endpoint: 24% female, median age 69 y (IQR 61-73); 75% had failed 1 prior systemic therapy vs 25% 2 prior therapies; 35% had ECOG-performance status 1; 33% had liver metastases. The median TMB was 6.9 mut/Mb. After median follow-up of 5 months, 33 pts have relapsed (52%). The median PFS was 5 months (95%CI: 4-not achieved). The confirmed objective response-rate (ORR) was 44.4% (95%CI: 0.34 to 0.55): 19 partial responses and 9 complete responses (14.4%). Grade 3-4 treatment-related adverse events (TRAE) were seen in 14 pts (22%). Most common any-grade TRAE included alopecia (76%), neutropenia (33.3%), and asthenia (33%). Permanent interruption of treatment (nPtx only) was seen in 9 pts (14.2%) due to toxicity. Neither TMB nor CPS were significantly associated with PFS on univariable analyses. Conclusions: Preliminary results from PEANUT study demonstrated a promising PFS and a clinically meaningful ORR in II-III line setting of advanced UC. Updated data, including mature OS, duration of response and biomarkers will be presented. Citation Format: Patrizia Giannatempo, Daniele Raggi, Elena Farè, Laura Marandino, Marco Bandini, Maurizio Colecchia, Filippo Pederzoli, Giuseppina Calareso, Russell Madison, Francesco Monopoli, Giusy Russo, Roberto Ferrara, Filippo De Braud, Francesco Montorsi, Andrea Necchi. Pembrolizumab and nanoparticle albumin bound paclitaxel (nab-paclitaxel) as salvage therapy for metastatic urothelial carcinoma (UC) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT187.

A Systematic Review and Meta-Analysis of Variant Histology in Urothelial Carcinoma of the Bladder Treated with Radical Cystectomy

The currently available evidence regarding the prognostic and clinical significance of each variant histology subtype of urothelial bladder cancer remains scarce. We assessed the prognostic value of variant histology in patients with urothelial carcinoma of the bladder treated with radical cystectomy. PubMed®, Web of Science™, Cochrane Library and Scopus® databases were searched for articles published before October 2019 according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. We identified 39 studies comprising 20,544 patients matching our eligibility criteria. Studies were deemed eligible if they compared overall, cancer specific and recurrence-free survival in patients with urothelial carcinoma of the bladder with and without variant histology. Formal meta-analyses were performed for these outcomes. Variant histology was associated with worse cancer specific (pooled HR 1.37, 95% CI 1.24-1.50), overall (pooled HR 1.44, 95% CI 1.26-1.65) and recurrence-free survival (pooled HR 1.32, 95% CI 1.20-1.45). Subgroup analyses demonstrated that "micropapillary" (pooled HR 1.20, 95% CI 1.02-1.41), "plasmacytoid" (pooled HR 2.03, 95% CI 1.17-3.52) and "small cell" variant histology (HR 3.32, 95% CI 1.98-5.59) were also associated with worse overall survival. Variant histology in patients with urothelial carcinoma of the bladder is associated with increased risks of disease recurrence as well as cancer specific and overall mortality. Variant histology was independently associated with overall survival in the "micropapillary," "plasmacytoid" and "small cell" subgroups. Variant histology should be integrated into prognostic tools to guide risk stratification, treatment planning and patient counseling. However, caution should be exercised in interpreting the conclusions drawn from this study given the limitations, which include the heterogeneity of the population of interest and the retrospective nature of the primary data evaluated.

Final results of PEANUT: Pembrolizumab and nanoparticle albumin-bound paclitaxel (nab-paclitaxel) as salvage therapy for metastatic urothelial carcinoma (UC).

5017 Background: Pembrolizumab (pembro) is a new standard of care in chemotherapy (CT) pre-treated patients (pts) with metastatic UC. Nab-paclitaxel demonstrated preliminary activity in advanced UC. In the PEANUT study (NCT03464734) we investigated their combination in advanced UC after CT failure. Methods: In an open-label, single-arm, phase 2 trial, pts received 200 mg pembro, intravenously (IV), on D1 and 125 mg/m2 IV nab-paclitaxel on D1 and D8, every 3 weeks, until disease progression (PD) or unacceptable toxicity. Inclusion criteria were: predominant UC histology, failure of ≤2 platinum-based CT for metastatic disease. Response was evaluated by RECIST v.1.1 criteria every 2 cycles. Biomarkers included PD-L1 combined positive score (CPS) and comprehensive genomic profiling on tumor and blood samples (FoundationONE and FoundationACT assay). The primary endpoint was the progression-free survival (PFS). The target was to detect an improvement in the median PFS from ≤3.0 months (H0) to ≥5.0 months (H1). Results: Between 01 and 12/2019, PEANUT study enrolled 65 pts: 24% were female, median age was 69 yrs (IQR: 61-73); 25% had failed &gt; 1 prior systemic therapies; 35% had ECOG-performance status 1; 33% had liver metastases. The median TMB was 6.9 mut/Mb. After median follow-up (FUP) of 5.5 months, 34 pts have relapsed (52.3%). The median PFS was 5 months (95%CI: 3-not reached). The 3-month PFS was 60.7% (95%CI: 49.8-74.1). The confirmed objective response-rate (ORR) was 47.7% (95%CI: 35.2-60.4): 22 partial responses and 9 complete responses (13.8%). The median duration of response was not reached, and 4 pts (6.1%) are long-term responders ( &gt; 12 months). Grade 3 treatment-related adverse events (TRAE) were seen in 20 pts (30.7%). Most common any-grade TRAE included alopecia (76%), neutropenia (33.3%) and asthenia (33%). Neither TMB nor CPS were significantly associated with PFS on univariable analyses. In matched tumor/blood samples, objective responses were seen in 8/10 pts with PI3KCA mutations (80%); 6/10 pts with RB1 alterations (60%); 5/12 pts with DNA damage repair gene alterations (41.7%). Conclusions: Pembro-nab-paclitaxel, the first salvage CT-immunotherapy combination in UC, demonstrated a good tolerability, promising PFS and a clinically meaningful ORR in II-III line setting of advanced UC. As more mature data on biomarker selection emerges, this combination warrants additional studies in either second-line or earlier disease settings. Clinical trial information: NCT03464734 .

Association of an immune gene signature with pathologic response and outcome after neoadjuvant pembrolizumab (pembro), compared to neoadjuvant chemotherapy (NAC), in muscle-invasive bladder cancer (MIBC).

533 Background: In the PURE01 study (NCT02736266), neoadjuvant pembro resulted in 42% pathologic complete responses (pT0) in patients (pts) with MIBC. In this study, we investigated immune transcriptome signatures and molecular subtyping as potential predictors of pembro efficacy. Methods: Pts enrolled in the PURE01, which is still recruiting pts in its amended design, had predominant urothelial carcinoma histology and stage cT≤4N0 MIBC. Biomarker analyses included transcriptome profiling for 78 pts. A cisplatin-based NAC cohort of 140 cT≤4N0 MIBC pts was used for comparison. The association of Immune190, immune hallmark RNA signatures and molecular subtypes (TCGA, Consensus classifier, Genomic subtyping classifier [GSC]) was evaluated with respect to pT0 and recurrence-free survival (RFS). Multivariable logistic regression analyses (MVA) were used adjusting for the clinical T-stage and gender. Results: The Immune190 signature was significant for pT0 on MVA (OR: 1.54, 95%CI: 1.1-2.3, p=0.02) in the PURE01 cohort, but not in NAC cohort (OR: 0.96, 95%CI: 0.8-1.2, p=0.73). The hallmarks for IFN-γ (OR: 1.10, 95%CI: 1-1.2, p=0.007) and IFN-α response (OR: 1.07, 95%CI: 1-1.1, p=0.009) were also associated with pT0 for PURE01, but not for NAC (IFN-γ: OR: 0.99, 95%CI: 0.9-1.1, p=0.846 and INF-α: OR: 0.99, 95%CI: 0.95-1.04, p=0.806). In PURE-01, patients with Immune190 scores &gt;0.35 had 100% 2-y RFS vs 80% of those with ≤0.35; no difference was observed in NAC pts, as well as for the other hallmarks in both groups. The neuroendocrine (NE)-like subtype had the worst 2-y RFS in all three subtyping models (33%, p&lt;0.01) whereas the GSC Claudin-low subtype had the best outcome with no recurrences within 24 months. The other subtypes had RFS ranging from 75-86% in TCGA, 53-89% in Consensus, and 74-92% in the GSC. Conclusions: We found RNA Immune190 signature was reliably associated with response and outcome after neoadjuvant pembro. Molecular subtyping revealed special subtypes with outlier outcomes. These data suggest RNA profiling may provide a potential tool for personalizing the neoadjuvant therapy approach. Clinical trial information: NCT02736266.

Impact of histology and toxicities on outcomes of patients with muscle invasive bladder cancer receiving neoadjuvant chemotherapy.

540 Background: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) extends survival in muscle invasive bladder cancer (MIBC) patients (pts). Pathologic complete response (pCR) is associated with survival. We conducted a retrospective study to examine the prognostic impact of other variables including histologic subtype, location, multifocality, margins, size of tumor and toxicities. Methods: Pts who underwent RC at Dana-Farber for MIBC stage T2-T4N0-1 were studied. Data were collected for demographics, clinical and pathologic variables. Descriptive stats were reported, and Cox proportional hazards regression analyses were conducted to examine the association with recurrence-free survival (RFS) and overall survival (OS). Results: From 2002 to 2018, 150 patients were available. The median age was 66 (range 36-89) and 102 (68%) were male. MVAC/dose dense MVAC, GC and other non-standard regimens were given in 42 (28%), 85 (56.7%) and 23 (15.3%) pts, respectively. The 2-yr RFS was 63.6%, the 5-yr OS was 68.7% and pCR occurred in 38 pts (25.3%). Multivariable analysis identified pure urothelial carcinoma in the residual tumor and absence of pathologic response to be associated with poor RFS and OS. Positive margins were associated with poor RFS, while grade ≥3 toxicities were associated with poor OS. Conclusions: Pure urothelial carcinoma histology was associated with worse RFS and OS following RC after NAC for MIBC, suggesting molecular studies may be useful in these cases. The association of severe toxicities with poor OS suggests that optimal pt selection for NAC and early recognition of toxicities is important.[Table: see text]

Interim results of PEANUT: pembrolizumab and nanoparticle albumin-bound paclitaxel (nab-paclitaxel) as salvage therapy for metastatic urothelial carcinoma (UC).

494 Background: Pembrolizumab (pembro) is a new standard of care in chemotherapy (CT) pre-treated patients (pts) with metastatic UC. Nab-paclitaxel (nPtx) demonstrated preliminary activity in advanced UC. In the PEANUT study (NCT03464734) we investigate their combination in advanced UC after CT failure. Methods: In an open-label, single-arm, phase 2 trial, pts receive 200 mg pembro, intravenously (IV), on D1 and 125 mg/m2 IV nPtx on D1 and D8, every 3 weeks, until disease progression (PD) or onset of unacceptable toxicity. Key inclusion criteria are: predominant UC histology, failure of ≤2 platinum-based CT for metastatic disease. Response is evaluated by RECIST v.1.1 criteria every 2 cycles. Biomarkers include PD-L1 expression with the combined positive score (CPS) and comprehensive genomic profiling on tumor and blood samples (FoundationONE and FoundationACT assay). The primary endpoint of the study is the progression-free survival (PFS). The target is to detect an improvement in the median PFS from ≤3.0 months (H0) to ≥5.0 months (H1). Results: Between 01 and 08/2019, PEANUT enrolled 46 pts evaluable for the study endpoint: 26% female, median age 66 y (range 43-78); 70% had failed 1 prior systemic therapy vs 30% 2 prior therapies; 24% had ECOG-performance status 1; 28% had liver metastases. The median TMB was 6.9 mut/Mb. After median follow-up of 5 months, 18 pts have relapsed (39%). The projected median PFS was 7 months (95%CI: 4-not achieved). The confirmed objective response-rate (ORR) was 47.8% (95%CI: 32.9-63.1): 18 partial responses and 4 complete responses (8.7%). Grade 3 treatment-related adverse events (TRAE) were seen in 6 pts (13%). Most common any-grade TRAE included alopecia (91%), asthenia (21.7%), and neutropenia (15%). Neither TMB nor CPS were significantly associated with PFS on univariable analyses. 7/8 pts with PI3KCA mutations in matched tumor/blood samples had an objective response (87.5%). Conclusions: Preliminary results from PEANUT study demonstrated a promising PFS and a clinically meaningful ORR in II-III line setting of advanced UC. Updated data, including mature PFS, duration of response and biomarkers will be presented. Clinical trial information: NCT03464734.