Association of DNA damage response (DDR) gene mutations (mts) and response to neoadjuvant cisplatin-based chemotherapy (chemo) in muscle-invasive bladder cancer (MIBC) patients (pts) enrolled onto SWOG S1314

4522

Background: Neoadjuvant cisplatin-based chemo followed by radical cystectomy (RC) is a standard of care treatment for pts with MIBC. DDR gene mts, including within ERCC2, a DNA helicase implicated in cisplatin sensitivity in MIBC, have been associated with higher pathologic (path) downstaging ( < pT2) and complete response (pT0) at RC and improved overall survival (OS) in retrospective series. S1314 randomized pts to one of 2 chemo regimens (dose dense MVAC or Gem/Cis) followed by RC. We sought to correlate ERCC2 and other DDR gene mts with response and survival in MIBC pts enrolled onto this prospective trial. Methods: Tumor and matched germline DNA from evaluable pts enrolled onto S1314 underwent exon capture sequencing of 505 cancer-associated genes (MSK-IMPACT). Both deleterious (del) mts and any mts in 9 DDR genes (ERCC2, ERCC5, BRCA1, BRCA2, RECQL4, ATM, ATR, RAD51C, FANCC) were correlated with clinical outcomes. The prespecified analyses included the association of mts with < pT2 and pT0 by logistic regression analysis and with progression-free survival (PFS) and OS by Cox proportional hazards regression. Results: 179 patients (median 61 years, 85% male, 87% white, and 87% clinical stage T2) who received >2 cycles of chemo and were evaluable for path response were included in the analysis. The pT0 rate was 28% and < pT2 was 41%. Del mts in ERCC2 were detected in 26 (14%) pts followed by ATM (n = 12, 7%), ATR (n = 3) and BRCA2 (n = 2). ERCC2 mts were associated with statistically significantly higher path responses with a 54% pT0 rate and 62% downstaging rate. Patients with any del mts had higher path response rates (51% pT0, 56% < pT2) and better PFS (Table) with a median follow-up of 53 months. There was a non-significant trend towards improved OS. Conclusions: In pts managed with neoadjuvant chemo and RC on S1314, both ERCC2 mts and del DDR gene mts correlated with pathologic response. Any del DDR gene mt was associated with improved PFS. These results are in line with retrospective analyses displaying a correlation between DDR gene mts and neoadjuvant chemosensitivity in MIBC and support ongoing genomically-informed organ sparing trials.[Table: see text]

S1314 correlative analysis of ATM, RB1, ERCC2, and FANCC mutations and pathologic complete response (pT0) at cystectomy after neoadjuvant chemotherapy (NAC) in patients with muscle invasive bladder cancer (MIBC): Implications for bladder preservation

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Background: SWOG S1314 (NCT02177695) was designed to validate the CoXEN classifier as a predictive biomarker in pts undergoing cystectomy after NAC. We repurposed banked DNA samples and prospective trial data from S1314 to further validate the predictive ability of the Philadelphia 4 gene signature (P4GS: any mutation in ATM, RB1, FANCC, ERCC2) to predict pT0 as previously reported (PMID: 26238431) and used in the RETAIN trial (NCT02710734). The RETAIN trial prospectively enrolled pts to receive NAC (DDMVAC) followed by allocation to bladder observation vs. intervention (cystectomy or RT) based on clinical evaluation and presence vs absence of P4GS. The primary objective of this correlative investigation was to determine whether presence of P4GS is predictive of pT0 at surgery. Methods: Eligibility for S1314 included cT2-T4a N0 M0 MIBC, cisplatin eligible, with plan for cystectomy; 237 pts were randomized between ddMVAC and gem/cis (GC) using standard dose/schedule. Of 167 pts who were evaluable for the original COXEN analysis (received 3+ cycles of chemo and evaluable for path response) adequate banked DNA was available for 105. Next-generation sequencing using the CARIS 592 Gene Panel (Caris Life Sciences, Phoenix, AZ) was performed. Pathogenic mutation or VUS of ATM, RB1, FANCC or ERCC2 was noted as present or absent for each pt and correlated with pT0 using logistic regression, adjusting for clinical stage. Results: Among the 105 pts, 51% ddMVAC, 49% GC. 15% female, 95% white, 15% clinical stage T3/T4a Prevalence of mutations: ATM (24%), ERCC2 (17%), FANCC (4%), RB1 (24%) and any variant 53%. Presence of any mutation correlated with pT0 (p = 0.0006), sensitivity 79%, specificity 59%. This association did not vary by treatment arm (MVAC vs. GC). The table below shows the contributions of each of the 4 genes with the greatest contribution from ATM and ERCC2. FANCC was non-contributory due to low prevalence. Conclusions: Patients with a mutation in ATM, RB1, FANCC or ERCC2 (P4GS) have a statistically significantly higher odds of a pT0 with GC or MVAC compared to those who do not have any variant. This signature was used to prospectively allocate patients to bladder observation as part of the RETAIN trial previously reported (ASCO GU 2021). RETAIN completed enrollment, final analysis of the primary endpoint – 2-year metastasis free survival – is expected later in 2022. Clinical trial information: NCT02177695.

Antiadenovirus Antibodies Predict Response Durability to Nadofaragene Firadenovec Therapy in BCG-unresponsive Non-muscle-invasive Bladder Cancer: Secondary Analysis of a Phase 3 Clinical Trial

A recent phase 3 trial of intravesical nadofaragene firadenovec reported a promising complete response rate for patients with bacillus Calmette-Guérin-unresponsive non-muscle-invasive bladder cancer. This study examined the ability of antiadenovirus antibody levels to predict the durability of therapeutic response to nadofaragene firadenovec. A standardized and validated quantitative assay was used to prospectively assess baseline and post-treatment serum antibody levels among 91 patients from the phase 3 trial, of whom 47 (52%) were high-grade recurrence free at 12 mo (responders). While baseline titers did not predict treatment response, 3-mo titer >800 was associated with a higher likelihood of durable response (p = 0.026). Peak post-treatment titers >800 were noted in 42 (89%) responders versus 26 (59%) nonresponders (p = 0.001; assay sensitivity, 89%; negative predictive value, 78%). Moreover, 22 (47%) responders compared with eight (18%) nonresponders had a combination of peak post-treatment titers >800 and peak antibody fold change >8 (p = 0.004; assay specificity, 82%; positive predictive value, 73%). A majority of responders continued to have post-treatment antibody titers >800 after the first 6 mo of therapy. In conclusion, serum antiadenovirus antibody quantification may serve as a novel predictive marker for nadofaragene firadenovec response durability. Future studies will focus on large-scale validation and clinical utility of the assay. PATIENT SUMMARY: This study reports on a planned secondary analysis of a phase 3 multicenter clinical trial that established the benefit of nadofaragene firadenovec, a novel intravesical gene therapeutic, for the treatment of patients with bacillus Calmette-Guérin (BCG)-unresponsive high-risk non-muscle-invasive bladder cancer. Prospective assessment of serum anti-human adenovirus type-5 antibody levels of patients in this trial indicated that a combination of post-treatment titers and fold change from baseline can predict treatment efficacy. While this merits additional validation, our findings suggest that serum antiadenovirus antibody levels can serve as an important predictive marker for the durability of therapeutic response to nadofaragene firadenovec.

Factors associated with improved outcomes in surgically resectable small cell urothelial cancer (SCUC)

495

Background: We have established that neoadjuvant (neo) chemotherapy (CTX) is the optimal strategy in localized SCUC given the frequent under staging. We have also demonstrated that alternating ifosfamide/doxorubicin (IA) and etoposide/cisplatin (EP) are active against SCUC; however, the optimal regimen has not been defined. Methods: We reviewed the records of 410 patients with SCUC treated at our institution between 1985 and 2020. Fisher’s exact test and logistic regression were used to determine the association between pathological complete response (pCR) and management approach. The Kaplan-Meier method was used to estimate overall survival (OS) from time of SCUC diagnosis to death or last follow up. Log rank test and Cox proportional models were used to determine the hazard-ratio (HR) between OS and management approach. Results: We included 203 patients with cT2-4aN0M0 SCUC who underwent cystectomy either after neoCTX (141, 69%), alone (38, 19%), or followed by adjuvant CTX (24, 12%). Clinical stage was cT2N0 (151, 74%), cT3/4N0 (44, 22%), or cTxN0 (8, 4%). Median age at diagnosis of SCUC was 66.7, 65.7, and 62.3 (p = 0.1) in the neoCTX, surgery alone and adjuvant CTX groups, respectively. Mean (+/- standard deviation) baseline glomerular filtration rate (GFR) was 75.6 (+/- 19.5), 61.3 (+/- 18.7), 70.5 (+/- 30.1) (p = 0.002) in the neoCTX, surgery alone and adjuvant CTX groups, respectively. Downstaging was significantly improved with neoCTX vs initial surgery (49.6% vs 14.5%, p <.0001), stage cT2N0 vs cT3/4N0 (44% vs 25%, p = 0.01), presence of carcinoma-in-situ (47% vs 28%, p = 0.01), or higher GFR (OR = 1.02, p = 0.06). In a multi-variable analysis of these factors, neoCTX was the only factor associated with pCR [OR = 3.9 (1.6-9.6) p = 0.003]. When comparing neoCTX regimens, downstaging was greatest with IA/EP (65%) as compared to EP (39%), MVAC/Gem/Cis (27%) or others (36%), p = 0.04. IA/EP was associated with younger age and good ECOG PS. In a multi-variable analysis of these factors, only IA/EP was associated with downstaging [OR = 3.7 (1.3-10.2), p = 0.01] and cT3/4 trended toward negatively impacting downstaging [OR = 0.5 (0.15-1.57), p = 0.23]. In the survival analysis, neoCTX, T2 vs T3/4, predominant small cell histology, good ECOG PS, higher GFR, and younger age were all significantly associated with improved outcomes. The best survival outcomes were observed with IA/EP (5-yr OS 64.2%), as compared to EP (5-yr OS 55.6%), MVAC/Gem/Cis (5-yr OS 50%) or others (5-yr OS 46.4%), p = 0.06, although these findings did not achieve statistical significance. Conclusions: NeoCTX remains the standard of care treatment for SCUC. The best downstaging was observed with IA/EP with a trend toward improved overall survival. We recommend the use of IA/EP whenever possible and consider EP for patients who are not able to tolerate ifosfamide.

Bladder tumor metabolic alterations in response to IFNα gene therapy

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Background: Intravesical interferon-alpha (IFNα) gene therapy with Nadofaragene firadenovec has shown clinical efficacy in patients with non-muscle invasive bladder cancer (NMIBC) in a phase III clinical trial, highlighting the therapeutic potential of this approach in a disease with significant unmet clinical need. Optimizing the clinical efficacy of IFNα gene therapy requires an understanding of the underlying therapeutic mechanisms. Here, we investigate the impact of IFNα gene therapy on tumor metabolism using in vitro and orthotopic murine preclinical models and clinical trial data to elucidate mechanisms of tumor resistance and identify predictive biomarkers. Methods: In vitro murine bladder cancer cell lines treated with recombinant IFNα (rIFNα) and lentiviral IFNα (LV-IFNα) were analyzed by whole-transcriptome sequencing, glucose uptake, and lactate production. Preclinical murine bladder cancer models were treated with LV-IFNα (orthotopic tumor model) or Poly(I:C) (flank tumor model), a potent IFN inducer. Disease response was monitored by in vivo real-time luciferase imaging. Tumors were harvested and whole-transcriptome sequencing performed to assess effects of IFNα therapy on tumor metabolism and lipidomics. Lipidomic profiling was performed on patient urine samples from a phase II clinical trial of intravesical Nadofaragene firadenovec (7 clinical responders and 6 non-responders) to assess for clinically-relevant differences in lipid metabolism. Results: Following IFNα therapy in vitro and in murine orthotopic bladder cancer models, we identified downregulation of genes involved in fatty acid synthesis and upregulation of genes involved in glycolysis by whole-transcriptome sequencing. This was confirmed by higher glucose uptake and lactate production by IFNα-treated cells in vitro. These findings were recapitulated in whole-transcriptome sequencing data of human bladder tumors treated with intravesical Nadofaragene firadenovec. Lipidomics performed on murine MB49 tumors treated with poly(I:C) identified 79 upregulated lipids, including phosphotidyl choline, spingomyelin and phosphatidyl ethanolamine, and 12 downregulated lipids, notably the cardiolipin class. Lipidomics performed on patient urine samples collected pre- and post-treatment with intravesical Nadofaragene firadenovec detected >592 lipids with distinct expression profiles differentiating clinical responders and non-responders at both timepoints. Conclusions: We describe novel modulation of glucose and lipid metabolism by bladder tumor cells in response to IFNα gene therapy. These metabolic changes were reproducible across in vitro, in vivo and clinical trial studies and improve our mechanistic understanding of IFNα gene therapy, identify tumor escape pathways targetable with combination therapy regimens, and identify a new class of biomarkers for predicting clinical response of NMIBC to IFNα gene therapy.

The prognostic and predictive implications of the 12-chemokine score in muscle invasive bladder cancer

466

Background: Adaptive anti-tumor immunity can be orchestrated by lymph node-like immune cell aggregates within the tumor microenvironment (TME) called tertiary lymphoid structures (TLSs). TLSs are postulated to be the gateway of lymphocyte infiltration into the TME, and are privileged sites for coordinated tumor antigen presentation and lymphocyte priming, differentiation, and proliferation, leading to a robust tumor-specific immune response. A 12-chemokine metagene grouping (12-CK score) has previously been described that correlates with the presence of TLSs in other solid tumor types. In this study, we explored the prognostic implication of the 12-CK score in bladder cancer and its correlation with the presence of TLSs. Methods: Cystectomy specimens from 132 patients with bladder cancer were arrayed on Affymetrix microarrays. 12-CK scores were normalized with > 1 denoting high scores (12-CKHi). Immunohistochemistry (IHC) antibody staining was performed for DC-LAMP, CD20, CD4, and CD8. A GU pathologist scored TLSs into Types I-III, with type III representing fully developed TLSs. The Fisher’s exact test was used to test the associations between the 12-CK scores and the type of lymphoid aggregate. Overall survival was estimated using the Kaplan Meier method. Findings were validated using 12-CK scores extracted from TCGA transcriptome sequencing data and the IMvigor210CoreBiologies package. Results: Twenty-five (n = 25) patients had 12CK scores > 1 and were classified as 12CK-High. Pathologic review of 43 bladder tumor specimens confirmed higher levels of Type III TLS patients (33% vs. 9%, p = 0.03), B cells (p = 0.002), CD8 T cells (p = 0.01), and activated DC (p = 0.01) in 12-CKHi compared to 12-CKLo. 12-CKHi was found to have a progression-free survival (PFS, HR 0.29, p = 0.003, Fig1a), disease specific survival (DSS, HR 0.29, p = 0.004, Fig1b), and overall survival (OS, HR 0.55, p = 0.03, fig1c) advantage compared to 12-CKLo in the Moffitt patient cohort. These results were validated using the publically available RNA expression data from TCGA. TCGA patients with 12-CKHi (18%,n = 72) had improved PFS ( HR 0.55, p = 0.007, fig1d), DSS (HR = 0.40, p = 0.002, fig1e), and 0S (HR = 0.59, p = 0.01, fig1f). From the IMVIGOR-210 patient who were 12-CKHi were more likely to have a complete response (p < 0.05, fig1g) and have a 11.2mo OS benefit (fig1h) after treatment using atezolizumab. Conclusions: Three important findings emerged from the current study: 12CK-High scores corresponded with formation of TLS in the TME; favorable prognosis in surgically treated MIBC patients; and CR in atezolizumab-treated patients. The findings herein suggest the 12CK gene signature to be a clinically actable biomarker for predicting response to immune checkpoint blockade. We believe the 12CK signature may serve as an important tool to refine patient selection for immune checkpoint blockade treatment.

Characterization of FOXF1 as a novel regulator of nodal metastasis in bladder cancer

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Background: Members of the forkhead transcription factor (FOX) family are important mediators of embryonic development and are known to be altered in a variety of cancers. The functional role of FOXF1 in bladder tumorigenesis and progression has not been clearly characterized thus far. This study investigated the clinical implications of differential FOXF1 expression in bladder cancer, and potential mechanisms by which its alteration can lead to tumor metastasis. Methods: Whole genome expression profiling was performed on paired primary tumors and nodal metastases from a radical cystectomy discovery cohort using Illumina HT12 v3-4 BeadChip arrays to identify FOXF1 as a top differentially expressed gene. Prognostic role of differential FOXF1 expression was validated on two independent cystectomy cohorts. Differential FOXF1 expression was also evaluated in murine orthotopic xenografts. Small interfering RNA was used to knock down FOXF1 in RT112 and UC6 bladder cancer cell lines to develop an in vitro model for assessment of metastatic potential. Next-generation sequencing and hierarchical clustering analysis were used to identify differentially altered genes secondary to FOXF1 knockdown. 186 biologically curated pathways were interrogated with internal validation to elucidate the downstream biologic mechanisms of metastasis. Results: In the discovery cohort, FOXF1 was a top differentially expressed gene with 3.6-fold lower expression in nodal metastases than paired primary tumors (n = 33, p < 0.001). Multivariable analyses in two validation cohorts (total n = 128) indicated that FOXF1 underexpression was associated with worse cancer-specific (p = 0.046) and overall survival (p = 0.006). Murine orthotopic xenografts (n = 13) established from human bladder cancer cell lines (UC3, UC6, UC14) showed FOXF1 underexpression in metastatic deposits compared with primary tumors (p = 0.004). Hierarchical clustering identified 40 differentially expressed genes between FOXF1-knockdown bladder cancer cell lines and their corresponding controls. Biological pathway interrogation showed differential enrichment for genes associated with mitogen-activated protein kinase signaling, focal adhesion and other carcinogenic pathways in FOXF1-knockdown cells compared with controls (normalized enrichment score ≥ 1.3). Conclusions: We identify and characterize FOXF1 as a novel regulatory molecule that potentially drives bladder cancer metastasis. This may be modulated through alterations in intracellular signaling and cellular adhesion. FOXF1 may serve as a prognostic biomarker that can identify patients at impending risk for metastasis who may benefit from more aggressive management.

Nomogram Predicting Bladder Cancer-specific Mortality After Neoadjuvant Chemotherapy and Radical Cystectomy for Muscle-invasive Bladder Cancer: Results of an International Consortium

BACKGROUND

Cisplatin-based neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) is associated with improved overall and cancer-specific survival. The post-NAC pathological stage has previously been reported to be a major determinant of outcome.

OBJECTIVE

To develop a postoperative nomogram for survival based on pathological and clinical parameters from an international consortium.

DESIGN, SETTING, AND PARTICIPANTS

Between 2000 and 2015, 1866 patients with MIBC were treated at 19 institutions in the USA, Canada, and Europe. Analysis was limited to 640 patients with adequate follow-up who had received three or more cycles of NAC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A nomogram for bladder cancer-specific mortality (BCSM) was developed by multivariable Cox regression analysis. Decision curve analysis was used to assess the model's clinical utility.

RESULTS AND LIMITATIONS

A total of 640 patients were identified. Downstaging to non-MIBC (ypT1, ypTa, and ypTis) occurred in 271 patients (42 %), and 113 (17 %) achieved a complete response (ypT0N0). The 5-yr BCSM was 47.2 % (95 % confidence interval [CI]: 41.2-52.6 %). On multivariable analysis, covariates with a statistically significant association with BCSM were lymph node metastasis (hazard ratio [HR] 1.90 [95% CI: 1.4-2.6]; p < 0.001), positive surgical margins (HR 2.01 [95 % CI: 1.3-2.9]; p < 0.001), and pathological stage (with ypT0/Tis/Ta/T1 as reference: ypT2 [HR 2.77 {95 % CI: 1.7-4.6}; p < 0.001] and ypT3-4 [HR 5.9 {95 % CI: 3.8-9.3}; p < 0.001]). The area under the curve of the model predicting 5-yr BCSM after cross validation with 300 bootstraps was 75.4 % (95 % CI: 68.1-82.6 %). Decision curve analyses showed a modest net benefit for the use of the BCSM nomogram in the current cohort compared with the use of American Joint Committee on Cancer staging alone. Limitations include the retrospective study design and the lack of central pathology.

CONCLUSIONS

We have developed and internally validated a nomogram predicting BCSM after NAC and radical cystectomy for MIBC. The nomogram will be useful for patient counseling and in the identification of patients at high risk for BCSM suitable for enrollment in clinical trials of adjuvant therapy.

PATIENT SUMMARY

In this report, we looked at the outcomes of patients with muscle-invasive bladder cancer in a large multi-institutional population. We found that we can accurately predict death after radical surgical treatment in patients treated with chemotherapy before surgery. We conclude that the pathological report provides key factors for determining survival probability.

Abstract IA03: Molecular subtypes of bladder cancer: Toward a more granular description of cancer heterogeneity

Whole-transcriptome mRNA expression profiling studies have established that muscle-invasive bladder cancers (MIBCs) can be subdivided into “basal/squamous” and “luminal” molecular subtypes that are associated with distinct biologic and clinical properties. In general, basal/squamous tumors tend to be more highly enriched in canonical cancer stem cell and epithelial-to-mesenchymal transition (EMT) biomarkers, and perhaps as a consequence, they are associated with advanced stage and metastatic disease at presentation. On the other hand, luminal tumors are enriched with breast cancer luminal biomarkers, peroxisome proliferator activator receptor (PPARG) expression and pathway activation, members of the miR-200 family of EMT repressors, and activating mutations and fusions targeting fibroblast growth factor receptor-3 (FGFR3). Past studies demonstrated that subsets of both basal and luminal MIBCs respond to neoadjuvant chemotherapy as measured by downstaging to &lt;pT2 at cystectomy, although clinical benefit is greatest in patients with basal tumors, perhaps because they are associated with more subclinical metastatic disease. Completed phase II clinical trials employing small-molecule FGFR inhibitors have confirmed that some patients whose tumors contain activating mutations in FGFR3 obtain clinical benefit, confirming that FGFR3 is a viable target in luminal tumors.

As the available datasets grow larger, it has become possible to further subdivide the basal/squamous and luminal tumors into additional molecular subtypes. A fraction of basal/squamous tumors lose expression of basal keratins, TP63, and E- and P-cadherins and exhibit molecular features of “complete” EMT. These tumors are similar to claudin-low breast cancers and appear to be more aggressive, exemplified in the observation that patients with claudin-low tumors fail to benefit from neoadjuvant chemotherapy. It appears likely that sarcomatoid tumors represent a phenotypic conversion to the extreme end of the EMT spectrum. Likewise, neuroendocrine and small cell bladder cancers also appear to evolve from basal/squamous tumors via mechanisms that involve combined inactivation of TP53 and RB1.

Although the general determinants of basal/squamous molecular heterogeneity appear relatively straightforward, the extent of the heterogeneity that exists in luminal tumors is still emerging. The Lund group's overall dichotemization of luminal tumors into “genomically unstable” and “urothelial” is extremely attractive, but the determinants of heterogeneity within the urothelial tumors await definition. TCGA and the molecular subtypes consensus group identified a small but clinically aggressive luminal subtype that seems somewhat similar to carcinoma in situ (CIS), but precisely how it corresponds to the other luminal subtypes is also unclear. Finally, micropapillary tumors are enriched in luminal biomarkers and overexpression of ERBB2, but their biologic determinants are also unknown. Because non-muscle invasive bladder cancers (NMIBCs) are highly enriched with luminal tumors, it seems likely that the luminal subtypes will become more granular as larger NMIBC datasets are merged with the MIBCs.

Citation Format: David J. McConkey, Woonyoung Choi, Colin P.N. Dinney, Arlene Siefker-Radtke, Bogdan Czerniak. Molecular subtypes of bladder cancer: Toward a more granular description of cancer heterogeneity [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr IA03.

Abstract IA21: Intravesical gene therapy for NMIBC

BCG is our most effective therapy for treating NMIBC, but over time, most patients will eventually recur. Alternative therapies to avoid cystectomy are needed as to date, only valrubicin, with a CR approaching 10% at 12 months in BCG-refractory CIS, has been FDA approved. Significant unmet need thus remains for an effective second-line therapy for patients facing cystectomy. The elucidation of a pathway for registration of new agents for BCG-unresponsive NMIBC has drawn the attention of pharma, and a variety of new approaches are under evaluation. Gene therapy is a promising approach for the management of BCG-unresponsive NMIBC. Effective gene transfer across the urothelium has been accomplished, and several agents are being evaluated in ongoing clinical trials. Coldgenesys reported a 47% CR at 6 months for BCG-unresponsive NMIBC using a replication-competent oncolytic adenovirus. The SUO CTC reported a 35% RFS at 12 months for patients treated with rAd-IFNα2b/Syn3 gene therapy in a phase II trial. The RFS for patients with papillary disease was 50% and the CR for patients with CIS was 30%. The SUO-CTC have recently completed recruitment for the phase III trial and further preclinical work has progressed to elucidate rAd-IFN/Syn3 treatment efficacy via predictive efficacy biomarkers for patient selection, vectors that might improve transduction efficiency and the design of novel therapeutic combination strategies to take advantage of rAd-IFN's immunologic activity.

Citation Format: Sharada Mokkapati, Jon Duplisea, Michael Metcalfe, Amy Lim, Vikram Narayan, Devin Plote, Debashish Sundi, James E. Furguson III, Nigel R. Parker, Seppo Yla-Herttuala, David McConkey, Kimberly S. Shluns, Colin P.N. Dinney. Intravesical gene therapy for NMIBC [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr IA21.

Safety and efficacy of intravesical nadofaragene firadenovec for patients with high-grade, BCG unresponsive nonmuscle invasive bladder cancer (NMIBC): Results from a phase III trial

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Background: Patients (pts) with BCG-unresponsive NMIBC are at significant risk for disease recurrence and progression. While cystectomy can be curative, many such pts are unwilling or unable given the attendant morbidity of surgery. To date, effective salvage intravesical therapies in this setting remain lacking. Nadofaragene firadenovec is a novel intravesical gene-mediated therapy that delivers the human IFNα2b gene resulting in IFNα2b expression that provided durable responses in a previous Phase 2 trial. Herein, we report the results from a follow-up Phase III trial of this agent for pts with BCG unresponsive NMIBC. Methods: This multicenter, open-label Phase 3 study investigated nadofaragene for high-grade NMIBC (CIS ± Ta/T1, or Ta/T1 alone) unresponsive to BCG. Nadofaragene (3X1011 vp/mL [75 mL]) was administered once every 3 months for up 4 doses in the initial 12 months, with additional dosing at the investigator’s discretion. The primary endpoint was complete response (CR) at any time in pts with carcinoma in situ (CIS). Results: A total of 157 pts (safety population, n=157; efficacy population, n=151) were enrolled. Among pts with CIS (n=103), 55 (53.4%) (95% CI, 43.3-63.3) achieved CR, all by month 3 after treatment. Of these 55 CIS CR pts, 25 (45.5%) remained free of high-grade recurrence at month 12, confirmed on protocol-mandated biopsy. For pts with HG Ta/T1 alone, 35 (72.9%) and 21 (43.8%) were free from recurrence at 3 and 12mos, respectively. Most treatment-emergent adverse events (TEAEs) were transient in nature: instillation site discharge 33.1%; fatigue 23.6%; bladder spasm 19.7%; micturition urgency 17.8%; hematuria 16.6%. There were 2 Gr4 TEAEs (sepsis and anaphylactic reaction, neither related to study drug) and no Gr5 TEAEs. Conclusions: Nadofaragene achieved CR in 53.4% of pts with BCG-unresponsive CIS, and was well tolerated. Responses were noted early and remained durable to one year. These data represent a potentially significant management advancement for a historically difficult to treat disease state. Clinical trial information: NCT02773849.

Lentiviral interferon with immune checkpoint blockade: A novel method for gene therapy in bladder cancer

33

Background: Gene therapy for bladder cancer (BLCA) is rapidly evolving. We reported that intravesical adenoviral interferon-alpha (Ad-IFNα) produced a complete response in 35% of patients with BCG-unresponsive BLCA enrolled in a Phase II trial. Lentivirus (LV) is another potential vector for intravesical delivery of IFNα. LV can infect non-dividing cells and integrate into the host’s genome, making it more efficient gene delivery vectors. As treatment with IFN upregulates checkpoint inhibitors, we also wanted to investigate the role of checkpoint inhibitors with and without IFN gene therapy. Methods: Murine BLCA cell lines were transduced in-vitro with LV-IFNα (MOI 2:1). IFNα levels were measured by ELISA. Cell viability was assessed using Trypan blue dye exclusion. qPCR was used to identify expression of IFNα target genes. A LV-βGalactosidase reporter construct was delivered intravesically, and urinary IFNα levels were measured in mice treated with LV-IFNα or control virus to assess gene transfer. To assess survival benefit, the MB49 intravesical tumor model and p53+/- C57/B6 mouse model were employed. We also assessed the role of combination therapy with immune checkpoint blockade using PD1 antibody using our MB49 intravesical model. Results: Efficient LV-IFNα transduction of BLCA cells resulted in increased expression of IFNα and its target genes and reduced cell viability vs. controls (p<0.001). Mechanistically, TRAIL dependent cytotoxicity in the LV-IFNα cells was rescued by Caspase8 inhibition. Urinary IFNα levels were elevated in mice receiving LV-IFNα compared with control virus. Overall survival improved in the MB49 model and BBN model in treated mice. LV-IFN induced intratumoral CD8+ T cell infiltration, high expression of PD-L1, and inhibited angiogenesis in BBN model whereas in the MB49 tumor response was mediated by TRAIL. Combination therapy with PD1 resulted in further improved survival. Conclusions: LV-IFNα effectively upregulated IFNα target genes, was cytotoxic to murine BLCA cells, and improved the survival in mouse models. Combining it with PD1 therapy appears to further improve survival.

A pilot presurgical study evaluating anti-PD-L1 durvalumab (durva) plus anti-CTLA-4 tremelimumab (treme) in patients (pts) with high-risk muscle-invasive bladder carcinoma (MIBC) who are ineligible for cisplatin-based neoadjuvant chemotherapy (NAC)

4551

Background: In MIBC pts, especially in those with high risk features including lymphovascular invasion, hydronephrosis, T3b disease, or variant histology, cisplatin-based NAC followed by cystectomy improves overall survival as compared with cystectomy alone. However, it is estimated that over 50% of pts with MIBC are ineligible for cisplatin-containing therapy. Therefore, we propose this pre-surgical trial with durva + treme for this population of pts. Methods: This is a single-arm, pre-surgical clinical trial with durva + treme in pts with localized, high-risk MIBC (cT2-T4a) who are ineligible for cisplatin-based NAC due to decreased renal function, neuropathy, hearing loss, or heart failure; or refuse cisplatin-based NAC (NCT02812420). Each patient receives durva (1500 mg) plus treme (75 mg) on weeks 1 and 5. Pts then undergo surgery at week 9-11. Pre- and post-treatment blood and tumor samples are collected for correlative biological analyses. Results: Twenty eight of 35 pts have been enrolled on this trial. Twenty-one pts have completed cystectomy as of 11/16/19. Of these 21 pts, 9 (43%) had pathologically complete response (pCR) and two (10%) had pathologic T1N0 (pT1) disease (≤pT1N0 rate = 52%). Fourteen of 21 (67%) had down-staging of disease. Of note, 10 of these 21 pts had 3-D mass (T3) on exam under anesthesia or clinical T4a disease; 5 of these 10 pts (50%) had pCR and one (10%) had pT1 disease (≤pT1N0 rate = 60%). Only 5 of 28 (17%) pts developed grade 3 immune related toxicity including hepatitis and amylase/lipase elevation, and two (7%) resulted in surgery delay for > 30 days. Immune profiling with CyTOF analysis of baseline peripheral blood indicates that pts with pCR have significantly lower frequency of a Th2 subset as compared to pts with up-staging of disease. In addition, gene expression profiling analysis of baseline tumor tissues demonstrates a significantly less immunosuppressive microenvironment in pts with pCR as compared to pts with up-staging of disease. Conclusions: Our data indicate that durva plus treme is an effective and safe neoadjuvant therapy for pts with MIBC ineligible for cisplatin-based therapy. Therefore, neoadjuvant therapy with durva + treme and a number of potential biomarkers warrant testing in a larger phase 3 trial. Clinical trial information: NCT 02812420.

A comprehensive assessment of postoperative complications in female patients undergoing robot versus open radical cystectomy

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Background: Radical cystectomy (RC) is the standard of care for non-metastatic, muscle invasive bladder cancer. Studies comparing robotic to open RC have found that the robotic approach confers non-inferior oncologic outcomes while potentially decreasing morbidity, but to date there have been no comparisons performed exclusively within female patients, who have unique anatomic considerations. Women undergoing RC may be at higher risk for urethral margin positivity, wound complications, and bleeding. Methods: Female patients who underwent either open or robot-assisted RC at the MD Anderson Cancer Center from 1/2014-6/2018 were identified. We assessed co-morbidities, pathologic data, and outcomes including complications. Descriptive statistics, along with uni- and multivariable logistic regression, were performed. Results: 122 female patients underwent either open (n=76) or robotic (n=46) RC. There were no statistically significant differences in age, BMI, smoking history, exposure to neoadjuvant chemotherapy, Charlson comorbidity index, or cTNM stages between the groups. In both uni- and multivariable models, open RC in females was associated with greater blood loss (median EBL 775 mL, IQR 600 mL) compared with robotic RC (median EBL 300 mL, IQR 350 mL), p<0.001. Female open RC was also associated with greater risk of transfusion compared to robotic RC (OR 6.2, 95% CI 2.7-14.3, p<0.001). Robotic RC conferred a higher median lymph node yield (27 nodes (range 7,57) vs 20 nodes (0,57), p, <0.001). Operative times were longer in the robotic cohort (median 507 min vs 388 min, p<0.001). There were no differences between robotic vs open groups in margin positivity (5.3% vs 4.4%, p≥0.99), length of stay (6.3 vs 6.9 days, p=0.32), or readmission rates at 30 (26.1% vs 22.7%, p=0.67) and 90 days (32.6% vs 28%, p=0.68). Conclusions: In this cohort of women undergoing RC, the robotic approach was associated with a lower risk of transfusion and EBL, and a higher median lymph node yield and operative time. Unique anatomic considerations in female patients and the improved visualization conferred by the robotic approach may be responsible for these findings, particularly with respect to blood loss.

Comparative analysis of biopsy proven lymph node positive bladder cancer patients to those with biopsy proven lymph node negative disease prior treatment

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Background: Many studies assessing the efficacy of chemotherapy before surgery include few clinically node positive patients or completely exclude them which make response rates in this particular subset of patients difficult to determine. Additionally, these patients are clinically node positive, making true nodal response rates unable to be determined. We report a descriptive analysis of patients with clinically node positive disease who underwent lymph node biopsy prior to any treatment and their outcomes. Methods: Data was obtained retrospectively from patients with cTanyN1-3M0 bladder cancer from 2006-2017 who underwent radical cystectomy at MD Anderson. SPSS was used for statistical analysis. Results: Among the 120 patients with cTanyN1-3M0 (median follow up 27.4 months), 40 patients underwent lymph node biopsy (LNBx). 26 (65%) patients had a positive LNBx, 14 (35%) were negative. 100% of the patients with a positive LNBx underwent primary chemotherapy. On final cystectomy, 9 (34.6%) of those patients had complete nodal response (pN0) and 9 (34.6%) had complete bladder response (pT0). 7 were pT0N0. Of the patients with a negative LNBx, 11 (78.6%) underwent neoadjuvant chemotherapy and of those patients, 7 (63.6%) were pN0 and 4 (36.4%) were pT0. Of patients that did not undergo LNBx that received primary chemotherapy (78 patients), 41 (52.6%) were pN0 and 22 (28.2%) were T0. There was no significant difference in overall or recurrence free survival between patients with a positive or negative biopsy or who did not undergo biopsy (p = .474). There was a significant improvement in overall and recurrence free survival in patients with negative nodal disease on final pathology compared to those with positive nodal disease (p < 0.001). Conclusions: Patients that had a negative LNBx were less likely to undergo primary chemotherapy. Pathologic bladder response rates correlate with nodal response rates. In cN+ patients, overall survival and recurrence free rates are not significantly different in patients without a lymph node biopsy, a positive biopsy or a negative biopsy. Finally, advanced final pathologic stage predicts worse outcomes.

Prophylactic cranial irradiation (PCI) significantly decreases risk of brain metastases in patients with bulky, higher stage small-cell urothelial cancer

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Background: Patients with bulky, higher-stage small cell urothelial cancer (≥T3b, N+, and/or M+) have a high risk of developing brain metastases. Siefker-Radtke et al reported a 50% risk of brain metastases in this patient population. Therefore, a prospective trial evaluating the potential benefit of PCI was undertaken. Methods: Thirty patients with stage ≥T3b, N+, and/or M+ disease (without brain metastases on MRI) were treated between 12/2008 and 5/2018 with PCI. Patients were treated to a total dose of 30 Gy in 2 Gy fractions over 3 weeks. The patient had baseline brain MRI and mini-mental status exam (MMSE) before the treatment began. After treatment, patients underwent MRI and MMSE every 3-4 months for one year and every 6 months thereafter. If the patients did not have M+ disease at diagnosis, they were also treated with neoadjuvant chemotherapy (usually consisting of cisplatin/etoposide alternating with Adriamycin/ifosfamide), followed by a radical cystectomy. The PCI was either given between the last cycle of chemotherapy and surgery or after the surgery. Both acute and chronic toxicity from PCI were measured using CTCAE 3.0. Change in the MMSE after PCI was evaluated using a t-test. Results: Twenty-nine patients were evaluable. Twenty-four patients had ≥T3b and/or N+ disease and 5 patients had M1 disease. Median follow-up was 22 months (range 8-103 months). Four patients have developed brain metastases with a median time of 11.5 months after PCI (range 3-23 months). Two of these patients have died. Nine other patients have died from progressive systemic disease, but they did not have evidence of brain metastases. PCI was well-tolerated, with no grade ≥2 toxicity seen. Acute grade 1 toxicity seen included headache, nausea, and dermatitis. MMSE were available for 19 patients with a median follow-up of 13 months (range 3-87 months). There was no significant change in the MMSE scores after the PCI when compared to baseline (p = 0.61). Conclusions: In this study, PCI decreased the risk of developing brain metastases in patients with bulky, higher-stage small cell urothelial cancer from 50% (historical) to 13.8% without significant toxicity. Clinical trial information: NCT00756639.

Let-7f microRNA expression within established bladder cancer subtypes and upregulation with recombinant interferon-alpha

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Background: Let7f is a microRNA (miR) that may act as a tumor suppressor in multiple human malignancies. In patients with BCG-refractory non-muscle invasive bladder cancer, detectable let7f levels in the urine of patients undergoing treatment with adenoviral vector-mediated IFNα gene therapy (clinical trial setting) were found to be prognostic of treatment response at 12 months. Here we sought to define the association of let7f with clinical bladder cancer phenotypes within The Cancer Genome Atlas (TCGA) cohort and characterize the role of let7f in preclinical models. Methods: Using miRNA sequencing data from the published TCGA 2018 bladder cohort (n = 412), let7f miR expression was characterized and stratified by molecular subtype (basal-squamous, luminal, luminal-infiltrated, luminal-papillary, and neuronal). Kaplan-Meier analyses were performed to compare survival (upper vs lower median, by let7f expression level). The murine urothelial carcinoma cell line MB49 was cultured in colonies of 105 and in vitro administrations of 100U/mL of recombinant mu-IFNα were performed with cells harvested at 0, 2, 8, 12, and 24 hours. Let7f miR expression levels were then determined by qRT-PCR. Results: Within the TCGA cohort, let7f expression levels were found to be lower in the more aggressive basal-squamous (median = 12.8), luminal-infiltrated (median = 12.9), and neuronal (median = 12.4) subtypes relative to the luminal (median = 13.2) and luminal-papillary (median = 13.3) subtypes (p < 0.001). Survival analysis demonstrated a trend towards improved survival in the high let7f expressers, but this did not reach statistical significance. In MB49 cells treated with mu-IFNα, there was a time-dependent increase in let7f miR expression suggesting that IFNα may play a role in upregulation of this potential tumor suppressor. Conclusions: Let7f miR is downregulated in more aggressive subtypes of MIBC. IFNα upregulates let7f expression in MB49 cells, and the inability to do so may comprise an escape mechanism for IFNα-treated tumors. Let7f miR may serve as a novel biomarker to identify aggressive phenotypes and treatment failures for bladder tumors treated with IFNα-based gene therapy.

Lentiviral interferon: A novel method for gene therapy in bladder cancer

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Background: Gene therapy for bladder cancer (BLCA) is rapidly evolving. We reported that intravesical adenoviral interferon-alpha (Ad-IFNα) produced a complete response in 35% of patients with BCG-unresponsive BLCA enrolled in a Phase II trial. Lentivirus (LV) is another potential vector for intravesical delivery of IFNα. Unlike the adenovirus, LV can infect non-dividing cells and integrate into the host’s genome, making it one of the most efficient gene delivery vectors. The objective of this study was to investigate lentiviral interferon-alpha (LV-IFNα) BLCA gene therapy in preclinical models. Methods: Murine BLCA cell lines were transduced in-vitro with LV-IFNα using a multiplicity of infection (MOI) of 2:1. IFNα levels were measured by ELISA. Cell viability was assessed using Trypan blue dye exclusion. qPCR was used to identify expression of IFNα target genes. A LV-βGalactosidase reporter construct was delivered intravesically, and urinary IFNα levels were measured in mice treated with LV-IFNα or control virus to assess gene transfer. To assess survival benefit, p53+/- C57/B6 mice were exposed to N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) to induce CIS and then treated with LV-IFNα or control virus, and sacrificed when moribund. Results: Efficient LV-IFNα transduction of BLCA cells was observed at an MOI of 2:1, resulting in increased expression of IFNα and its target genes PDL-1, TRAIL, and IRF7 (p<0.001), and reduced cell viability vs. controls (p<0.001). Mechanistically, TRAIL dependent cytotoxicity in the LV-IFNα cells was rescued by Caspase 8 inhibition. βGal expression confirmed efficient transduction of murine urothelium. Urinary IFNα levels were elevated in mice receiving LV-IFNα compared with control virus. BBN mice treated with LV-IFNα had longer overall survival than mice treated with control virus (p=0.04). LV-IFNα induced intratumoral CD8+ T cell infiltration, high expression of PD-L1, and inhibited angiogenesis. Conclusions: LV-IFNα effectively upregulated IFNα target genes, was cytotoxic to murine BLCA cells, and improved the survival of BBN tumor-bearing mice. LV appears to be a promising vector for intravesical gene delivery.

A comparison of pathologic and intermediate term oncologic outcomes following open and robotic radical cystectomy

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Background: Conflicting data regarding the oncologic efficacy of robotic surgery has led to concerns for possible inferiority. Despite recent prospective results from the RAZOR trial demonstrating non-inferior progression free survival, results from another prospective randomized trial from Memorial Sloan Kettering suggests a possible difference in the pattern of recurrences. We examined our experience with both open (ORC) and robotic radical cystectomy (RRC) with the objective of establishing recurrence patterns and pathologic comparisons at a high volume tertiary referral center. Methods: We performed a retrospective cohort study at a high volume academic tertiary referral center for patients who underwent radical cystectomy (RC) for bladder cancer from 2005 to 2017. The surgical choice of RRC or ORC is based on provider preference. A multivariable analysis was carried out to determine factors predictive of recurrence free survival (RFS) and overall survival after RC. Analysis was done with SAS 9.4. Results: 1813 patients were identified, 10% underwent RRC and no difference in recurrence patterns were found compared to ORC. There was no difference in the severity of pathology distribution between the two cohorts. There was no difference in positive surgical margin status, 2.4% in ORC and 1.1% in RRC. Peritoneal carcinomatosis was seen in 1.1% of ORC and 0.5% in RRC. Shorter RFS was associated with younger age (HR 1.04, 95%CI 1.03-1.05, p<0.001), neoadjuvant chemotherapy (HR1.55 95%CI 1.32-1.82, p<0.001), higher pathologic stage (stage T4 HR 4.38, 95%CI 3.17-6.06, p<0.001), positive lymph nodes at RC (HR 1.82 95%CI 1.53-2.17, p<0.001) and positive surgical margins (HR 1.50 95%CI 1.19-1.89, p<0.001). At a median follow up of 60 months neither progression free or overall survival for ORC compared to RRC was significantly different. Conclusions: The data from this study supports continued use of RRC as a safe oncologic procedure with similar outcomes to ORC.

The role of metastatic burden in cytoreductive/consolidative radical cystectomy

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Background: The strategy of surgical extirpation of the primary tumor in the setting of metastatic disease has gained acceptance for a variety of solid tumors. The role of cytoreductive/consolidative radical cystectomy (CCRC) for metastatic urothelial cancer (UC) is unknown. We aimed to describe our institutional experience with CCRC for metastatic UC and to investigate clinicopathologic features predicting prolonged cancer specific survival (CSS) following CCRC. Methods: We performed IRB approved review of our bladder cancer database, and identified 32 patients with metastatic cancer originating from the lower urinary tract who underwent CCRC. Of these, two patients had non−UC histology. Baseline demographics, regimen of chemotherapy, clinicopathologic features, and perioperative complications were collected. Progression free survival (PFS) and cancer specific survival (CSS) were estimated from the time of CCRC. Univariate and multivariate Cox regression models were used to identify predictors of improved CSS after CCRC. Results: Of the 32 patients, 19 (59%) had clinical evidence of distant metastases, while 13 were found to harbor occult metastases on the surgical specimen. The most common site of metastasis was the retroperitoneal lymph nodes, found in 17 patients. Solitary metastases were found in 19 patients (59%). Twenty−eight (88%) patients received chemotherapy prior to CCRC. Disease progression was detected in 29 patients after CCRC (median PFS 4.5 mo), while 28 died of metastatic cancer (median CSS 11.7 mo). On multivariate analysis, patients with solitary metastases were found to have improved CSS compared to those with multiple metastases (HR 2.51, 95% CI 1.06−5.92, p = 0.04), with median CSS of 16.9 mo vs. 5.6 mo (p = 0.003). Median postoperative LOS was 10 days. Overall, 59% suffered postoperative complications, including one perioperative mortality. Conclusions: CCRC is feasible in the setting of metastatic UC, with comparable perioperative morbidity and mortality to RC with curative intent. Patients with solitary metastasis demonstrated longer CSS than those with multiple metastases, and should be considered candidates for future trials evaluating the role of CCRC for metastatic UC.

Using grade of tumor recurrence after BCG to guide further therapy

523

Background: Tumors that recur after BCG therapy are considered to be high risk and patients are often recommended to undergo radical cystectomy (RC). However, the nuances associated with the grade of tumor recurrence after BCG treatment are not well understood. We aimed to characterize the pattern of bladder cancer progression and cancer specific survival (CSS) in patients with recurrences dichotomized by low grade versus high grade after intravesical BCG treatment. Furthermore, to assess the safety of continued bladder sparing therapy in these patients. Methods: We performed an IRB approved review of our bladder cancer database. Overall, 146 NMIBC patients were found to have tumor recurrence after induction BCG with/without maintenance therapy, 38 with LG and 108 with HG tumors. Baseline clinicopathologic characteristics including age, gender, primary tumor grade, stage, size, multiplicity and concurrent CIS were collected and compared between the two groups. The primary endpoint was PFS, with progression defined as the development of MIBC/distant metastasis. In addition, RFS, HG RFS, CFS, and CSS were also compared. Multivariable analysis was performed using the Cox regression model. All tests were two-sided and p < 0.05 was considered statistically significant. Results: As dichotomized by grade of recurrent tumor, estimated 5-year PFS was 85.6% (95% CI 60.8 - 95.2%) for those with LG recurrence and 67.9% (95% CI 54.1 – 78.4%) for those with HG recurrence. On KM analysis, patients whose initial LG recurrence on BCG therapy had improved subsequent RFS (5.2 vs. 2.8 yrs, p = 0.007), HG RFS (9.4 vs. 3.0 yrs, p < 0.001), CFS (p < 0.001), and compared to those who had a HG initial recurrence; CSS benefit approached significance (3.7 vs. 2 yrs, p = 0.12). Grade of tumor recurrence after BCG was an independent predictor of PFS (HR 3.7, 95% CI 1.3-10.9, p = 0.016). Conclusions: Grade of tumor recurrence after intravesical BCG is an important predictor of bladder cancer progression to MIBC/MUC. However, patients who have low grade recurrences on BCG still may progress and hence should be carefully counselled on bladder sparing therapy.

A new 50-gene molecular subtype classifier: An evaluation of subtype stability and association with response to neoadjuvant chemotherapy in muscle-invasive bladder cancer

519

Background: The bladder cancer basal and luminal molecular subtypes have been associated with differential progression patterns and responses to neoadjuvant chemotherapy. However, they are typically identified by whole transcriptome expression profiling, which may be impractical for most academic centers. To make subtype classification more accessible, we developed a 50-gene basal and luminal subtype classifier and examined its performance in matched tumor specimens, including pretreatment biopsies from patients treated with neoadjuvant chemotherapy. Methods: We refined a 50-gene subtype classifier derived from a oneNN classifier containing >~2000 genes that we previously developed using unsupervised methods. We compared its accuracy against calls made using the original oneNN classifier, including 148 tumors from a neoadjuvant chemotherapy meta dataset. To test subtype stability, tumors in 2 different datasets (30 sets of matched primary and lymph node tumors and 43 sets of matched pre- and post-chemotherapy tumors) were assigned using 50-gene subtype classifier with Linear Discriminator Analysis (LDA) prediction algorithms. Results: In the NAC cohort, patients with tumors assigned to the basal subtype by the 50-gene classifier had better survival outcomes compared to the luminal tumors, consistent with the conclusion generated with the parent classifier (p<0.05). Basal subtype assignments were stable in 62.5 % of pairs, whereas luminal tumors displayed 100% stability. In matched pre- and post-chemotherapy tumors, basal tumors displayed 78% stability while luminal tumors showed 94% stability. Conclusions: Based on these preliminary data, it appears that basal tumors display higher plasticity than luminal tumors with these specific contexts. This plasticity may interfere with precise subtype predictions with tumors assigned to the basal subtype at biopsy.

Genomic analysis of same-patient metachronous upper-tract and bladder urothelial carcinoma

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Background: Despite similarities between upper-tract (UTUC) and bladder urothelial carcinoma (BUC), distinctive clinicopathologic and genomic differences are being described. We further investigate the genomic landscape of these two interrelated malignancies in same-patient metachronous (m) UTUC and BUC using next generation sequencing (NGS). Methods: Following institutional board approval, UTUC and BUC samples were obtained from patients via surgical resection or endoscopic biopsy. Tumors were macrodissected from unstained formalin-fixed, paraffin-embedded slides. Study inclusion was untreated patient samples of UTUC and/or BUC divided into 4 groups: 1) UTUC with mBUC, 2) BUC with mUTUC, 3) Synchronous BUC and UTUC, 4) UTUC with no bladder history. Exclusions were for inadequate clinical data or histological tumor purity < 30%. Whole transcriptome RNA sequencing was performed and analyzed using BASE47 panel (includes basal, luminal, p53-like and cell cycle genes). Results: A total of 95 (UTUC = 61, BUC = 34) samples from 40 patients were analyzed. UTUC samples were 33 primary ureter and 28 renal pelvis cancer. Median age was 72 years, 68% male, 76% Caucasian, 60% former smokers. Groups samples were: 1) UTUC (n = 19), mBUC (n = 12); 2) BUC (n = 12), mUTUC (n = 9); 3) Synchronous UTUC/BUC (n = 10); and 4) UTUC (n = 23). Unsupervised hierarchical clustering segregated tumors into basal-like and luminal subtypes, with 87.5% of metachronous tumors displaying conserved subtype membership. For the groups with UTUC and BUC, only 3/24 (12.5%) clusters (2 patients in Group 2, and 1 patient in Group 3) had unmatched basal/luminal subtypes. Conclusions: NGS analysis of same-patient metachronous UTUC and BUC shows that the majority stay within the same molecular subtype regardless of chronologic development or anatomic origin. Additional studies are necessary to explore differences that may occur within the subtypes, the role of methylation, and clinical correlates.

Non-seminomatous germ cell tumor with bone metastasis only at diagnosis: A rare clinical presentation

Bone metastasis of non-seminomatous germ cell tumors (NSGCT) of the testes is a rare event and even more uncommon at initial presentation. Generally, bone lesions are discovered in the presence of concurrent retroperitoneal lymph node or visceral disease. However, in this case, a 37 years old male complaining of a growing testicular mass was found to have isolated bone metastasis with associated caudaequina syndrome without apparent abnormal findings on initial computed tomography (CT) scans. Continued neurologic symptoms prompted further evaluation with magnetic resonance imaging (MRI), which demonstrated multiple sites of bone metastasis without evidence of retroperitoneal lymph node or visceral organ involvement. This case represents a rare clinical presentation and disease manifestation of NSGCT.

Prognostic significance of geriatric assessment

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Background: More than 60% of cancer patients are older adults, and by 2020 the proportion of older adults with cancer will rise to 70%. Objective: To assess risk factors for overall survival (OS) in older cancer patients seen in a comprehensive cancer center. Methods: This is a single center, retrospective cohort study of older cancer patients (65 years of age and older). Patients receiving active cancer care underwent comprehensive geriatric assessment (including cognitive, mood, functional, nutritional, physical, and comorbidity assessment using validated scales). Hematologic, and solid tumors (urologic, breast, gastrointestinal cancers) were evaluated. Targeted interventions were implemented. Analysis: Univariate and multivariable Cox proportional hazards regression analysis were performed to identify factors associated with OS (SAS 9.4). Results: Among 304 eligible patients, the median follow-up was 12.7 months, 98 (32%) died, the median OS was 25.4 months. Median age is 78 years. Univariate analysis revealed known risk factors for mortality (advanced age [p = 0.004], and metastatic disease [p = 0.002]), functional impairment (ADL scores 0-4, p = 0.02), and major depression (p = 0.005). Comorbidity (p = 0.07) and functional impairment showed a marginal significance on OS. Factors with a univariate p-value less than 0.1 were considered in multivariable regression models. A final multivariable model included age group, cancer stage, functional impairment, and major depression. Risk factors for OS include major depression (HR 1.88 (95% CI, 1.12, 3.15), p-value = 0.02), functional impairment (HR 2.47 (95% C.I. 1.28, 4.74), p = 0.007), and metastatic disease (HR 2.2 (95% C.I. 1.30, 3.97), p = 0.004). Conclusions: Major depression and functional impairment were identified as risk factors for OS in older cancer patients. Prospective studies are recommended.

Outcomes and survival in nonbilharzial pure squamous cell bladder cancer in patients undergoing curative radical cystectomy

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Background: Pure squamous cell cancer of the bladder is uncommon in the United States. Because squamous cell bladder cancer is rare, there are no large studies with details on optimal preoperative neoadjuvant therapies and long-term outcomes. To improve the overall knowledge of the disease this study sought to provide a contemporary update in a single center cohort. Methods: A retrospective cohort study was performed. 57 patients had a radical cystectomy (RC) for pure nonbilharzialsquamous cell bladder cancer between 1995 and 2015. Demographics, risk factors for squamous cell bladder cancer, pathology, and outcomes were reviewed and compared with descriptive statistics. Advanced disease was defined as ≥ T3/T4 disease and any positive lymph node metastasis. Logistic regression was used to identify predictors of overall survival (OS), disease specific survival (DSS) and recurrence free survival (RFS). Kaplan-Meier curves were used for survival prediction. Results: With a median follow up of 24 months (IQR 9.7-131.8 months), 12 (21.4%) had a recurrence. The median time to recurrence was 15.5 months (IQR 5.0-20.0 months). Recurrence was most common in the pelvis, n = 5(62.5%). 20 had neoadjuvant chemotherapy (NAC), 16 of which it was combined with external beam radiation (XRT). 50.8% of patients had advanced pathology. 5-year OS was 59.7%. To predict RFS all of the following were adjusted for: age, stage, advanced pathology, nonbilharzialsquamous cell risk factors, lymphovascular invasion, and number of lymph nodes removed at RC. Predictors of RFS were combined NAC and XRT, pathologic T-stage, advanced disease (p = < 0.01, p = 0.02 and p = 0.02, respectively). Predictors of DSS were pathologic T-stage and node positive disease (p = 0.04 and < 0.01, respectively). OS was best predicted by clinical stage, p < 0.001. Conclusions: The combination of NAC and preoperative XRT may provide a RFS advantage in nonbilharzialsquamous cell bladder cancer. Those with clinically advanced disease continue to have a poor prognosis. However, OS does seem to have an improved prognosis compared to previous reports.

Association of presurgery neutrophil-to-lymphocyte ratio with survival outcomes in patients with urothelial carcinoma treated without neoadjuvant chemotherapy and with radical cystectomy

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Background: There is growing interest in finding inexpensive, easily reproducible biomarkers to predict outcomes in patients with urothelial bladder carcinoma (BC). An elevated preoperative neutrophil-to-lymphocyte Ratio (NLR) has been found to be an independent prognostic factor for decreased survival, predictive of upstaging at radical cystectomy (RC), and predictive of recurrence and progression. This study investigated the utility of the preoperative NLR predicting long-term outcomes in chemotherapy naïve patients undergoing RC for BC at a large tertiary care center. Methods: In a retrospective cohort study, 849 RC patients with BC were identified between 2000 and 2011. NLR data for these patients was obtained within 30 days prior to RC. Univariate CART analysis was used to determine an NLR cutoff point that was significantly associated with both overall survival (OS) and disease specific survival (DSS). OS and DSS were estimated using Kaplan-Meier curves. Results: The median follow-up time among survivors was 7.3 years. 597 (70%) patients died and 252 (30%) were alive at last follow. Using CART analysis, a preoperative NLR cutoff point of 3.19 was identified to have the strongest association with both OS and DSS (p < 0.001). 562 (66%) patients had a preoperative NLR < 3.19 and 475 (34%) had a preoperative NLR ≥ 3.19. The median OS and DSS for patients with preoperative NLR < 3.19 was 5.96 years and 15.64 years, respectively. The median OS and DSS for patients with a NLR ≥ 3.19 was 4.44 years (95% CI: 3.18-4.81 years) and 8.23 years (95% CI: 5.15-11.87 years). DSS Kaplan-Meier curve was significant, p < 0.001. Patients with a NLR < 3.19 had a 5-year OS and DSS of 59% and 77%, respectively. RC patients with a NLR ≥ 3.19 had a 5-year OS and DSS of 43% and 56%. Conclusions: A preoperative NLR ≥ 3.19 is significantly associated with decreased OS and DSS in patients treated with RC for UC. This finding further validates NLR as a biomarker in BC prognosis. NLR can help to determine patients with a poor prognosis who may benefit from more aggressive, adjuvant therapy following RC.

Does liposomal bupivacaine use intraoperatively decrease postoperative narcotic use in radical cystectomy patients?

311

Background: Bupivacaine liposome injectable suspension (LB) can be used to help control postoperative pain. It slowly releases bupivacaine for up to 96 hours after injection. This study sought to determine if the use of LB intraoperatively for radical cystectomy (RC) patients decreases postoperative narcotic use. Methods: A retrospective cohort study was performed. 281 patients underwent RC between November 2013 and May 2016, 203 received LB. LB was administered after fascial closure but before skin closure by performing suprafascial and subfascial injection with 20ml of LB. Patient demographics, BMI, renal function, operative characteristics, and the total postoperative intravenous morphine equivalents were reviewed. Where appropriate chi-squared, Mann-Whitney and t-tests were used for statical analysis. Multivariable analysis and linear regression models were performed. Because enhanced recovery principles were used simultaneously, enhanced recovery status was also used to adjust for predictors of post-operative opioid use. Results: There was no difference in baseline demographics, BMI, renal function or baseline opioid use between the LB and non-LB group. The operative time was longer in those who had LB administered and there were more open RCs performed in the LB group. Total morphine equivalents averaged to 8.0 mgs for the LB group and 50.7 mgs for the non-LB group, p-value <0.001. More patients had epidurals and IV PCA pumps in the non-LB group, (p=0.001 and <0.001, respectively). There were 42 patients whom did not require any IV morphine equivalents in the LB group compared to only 4 in the non-LB group (p=0.002). After adjusting for modality, and operative time, the linear regression model was predictive of less IV morphine equivalents in those with LB, p=0.044. Conclusions: The addition of LB to enhanced recovery principles increases the number of patients with zero narcotic use postoperatively. Irrespective of open or robotic modality and operative time, LB use decreases opioid use after RC.

Association of preoperative neutrophil-to-lymphocyte ratio with survival outcomes in patients undergoing radical cystectomy, regardless of neoadjuvant chemotherapy status

352

Background: Pre-operative neutrophil-to-lymphocyte ratio (NLR) has been found to be associated with adverse pathological results and poor long-term outcomes in patients treated with radical cystectomy (RC) for urothelial bladder carcinoma (BC). Prior studies have determined inclusion based on neoadjuvant chemotherapy (NAC) status. This study aimed to evaluate pre-operative NLR in a large cohort without exclusion as a predictor of long-term outcomes in patients undergoing RC for BC. Methods: A retrospective cohort study was performed of 1243 patients undergoing RC between 2000 and 2011. NLR was summarized using descriptive statistics. Univariate classification and regression trees analysis (CART) was applied to identify subgroups of patients using pre-surgery NLR as the covariate and overall survival (OS) or disease specific survival (DSS) as the outcome of interest. The probabilities of OS and DSS were estimated using the Kaplan-Meier method. Results: The median follow-up time among survivors was 7 years. 863 (69%) patients died and 380 (31%) were alive at last follow-up. The median OS was 5.2 years (95% CI: 4.9-5.5 years). Using CART analysis, the strongest association with OS was the cutoff point 3.09. 767 (62%) patients had pre-surgery NLR < 3.09 and 475 (38%) had pre-surgery NLR ≥ 3.09. The overall survival was found to be significantly associated with NLR < 3.09 vs. ≥ 3.09 (p < 0.001). The median OS for patients with NLR < 3.09 and ≥ 3.09 was 5.9 years (95% CI: 5.3-6.3 years) and 4.2 years (95%:3.3-4.7 years), respectively. Patients with NLR < 3.09 and ≥ 3.09 had 5-year OS of 56% and 44%, respectively. DSS was found to be significantly associated with NLR ≥ 3.09 vs. < 3.09 (p < 0.001). The median DSS for patients with pre-surgery NLR < 3.09 and ≥ 3.09 were 15.6 years and 7.5 years, respectively. Conclusions: The NLR significantly predicts OS and DSS in RC patients. NLR should be taken into consideration as NAC and adjuvant treatments are considered in BC patients to help improve survival.

Intravesical rad-IFNα/Syn3 for patients with high-grade, bacillus Calmette-Guérin (BCG) refractory or relapsed non-muscle invasive bladder cancer: A phase II randomized study

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Background: While bacillus Calmette-Guérin (BCG) is the most effective intravesical treatment for reducing recurrence and progression for high-risk non-muscle invasive bladder cancer (NMIBC), many patients are either refractory to treatment or relapse. We assessed the efficacy and safety of rAd-IFNα/Syn 3 (Instiladrin, FKD Finland), a replication deficient recombinant adenovirus gene transfer vector, for patients with high-grade (HG) BCG refractory or relapsed NMIBC. Methods: In this open-label, US multicenter (n=13), parallel-arm Phase II study (NCT01687244), 43 patients with HG BCG refractory or relapsed NMIBC were randomized 1:1 to receive intravesical rAd-IFNα/Syn3 at 1x1011 or 3x1011viral particles/mL. Patients responding at months 3, 6, and 9 were re-treated at months 4, 7, and 10. Most patients (n=21) had a primary tumor classification of carcinoma in situ (CIS); 9 had both CIS and Ta/T1 disease and 10 had Ta/T1 disease alone. The primary endpoint was 12-month HG recurrence-free survival (RFS). All patients receiving at least one dose were included in efficacy and safety analyses. Results: Forty patients received rAd-IFNα/Syn3 (1 x 1011 vp/mL: n=21; 3 x 1011vp/mL: n=19) between November 2012 and April 2015. Fourteen patients (35.0%; 90% CI 22.6%, 49.2%) remained free of HG tumor recurrence 12 months after initial treatment. Comparable 12 month HG RFS was noted between dosage arms, as well as between patients with refractory and relapsed NMIBC. Interestingly, the 12 month HG recurrence-free survival for patients with Ta/T1-only disease was 50% (5/10). rAd-IFNα/Syn3 was well-tolerated, with no Grade 5 adverse events (AEs), one Grade 4 AE (COPD; unrelated to treatment), and no patient discontinuing treatment due to an adverse event. The most frequently reported AEs were micturition urgency (n=16), dysuria and pollakiuria (n=13 each), fatigue (n=9), and nocturia (n=10). Conclusions: rAd-IFNα/Syn3 was well tolerated and demonstrated promising efficacy for patients with HG NMIBC after BCG therapy who are unable or unwilling to undergo radical cystectomy. A phase III trial utilizing this novel agent is ongoing. Clinical trial information: 01687244.

Clinical and pathological outcomes for patients with T1HG bladder cancer managed with upfront cystectomy with or without neoadjuvant chemotherapy and the impact of the MDACC high-risk features

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Background: In muscle invasive bladder cancer there is an increased risk for systemic disease identified for patients with certain high risk features (HRF): pre-operative hydronephrosis (POH), lymphovascular invasion (LVI), abnormal exam under anesthesia (AbnEUA), and the presence of variant histology (VH). We sought to identify the effect of these high risk features in the T1HG population. Methods: With IRB approval, a single center retrospective review was performed on all patients at MDACC from 1995-2013 who underwent radical cystectomy (RC) for T1HG urothelial cancer. Patients were stratified according to the presence or absence of HRF defined by the presence of LVI, POH, VH, AbnEUA, prostatic ductal involvement (PDI), and the delivery of neoadjuvant chemotherapy (NAC). Primary outcome included pathologic T (pT) upstage and presence of lymph node positive disease (LN+) at time of RC, as well as survival outcomes. Results: 372 T1HG patients underwent RC, of these 196 (53%) have HRF including: VH (n=98, 25%), LVI (n=44, 12%), PDI (n=31, 8%), POH (n=38, 10%) and/or AbnEUA (n=34, 9%). pT upstage occurred in 43/176 (24.4%) of patients without HRF, in 45/151 (30%) of patients with 1 HRF, and in 38% (17/45) of patients with > 2 HRF (p=0.088). LN+ occurred in 18/176 (10.2%) of patients without HRF, 7.8% (15/151) of patients with 1 HRF and in 17.8% (8/45) of patients with > 2 HRF (p=0.0403). Presence of HRF were not significant for a decreased OS (p=0.076), DSS (0.425), and RFS (p=0.103). No patients without HRF got NAC, and 41/196 (21%) of patients with HRF received NAC. There was no effect of NAC on pT upstage (OR 1.184, 95% CI 0.355-3.954, p=0.7834) or rate of LN+ disease (OR 1.758, 95% CI 0.669-5.606, p=0.2525) on multivariate analysis. There was no effect of NAC on OS (p=0.122), DSS (0.437), or RFS (0.7483). Conclusions: Presence of certain high risk features in the T1HG setting does have increased risk of pT upstage and LN+ disease in patients treated with cystectomy. However, there is no effect seen on survival outcomes. Use of NAC did not significantly alter outcome in our cohort and should be reserved for the muscle invasive setting.

Measuring and improving symptom burden in radical cystectomy patients undergoing traditional care compared to enhanced recovery

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Background: Bladder cancer is a disease of the elderly associated with high morbidity in those undergoing radical cystectomy (RC). The Optimized Surgical Journey (OSJ) uses enhanced recovery after surgery (ERAS) principles for RC patients to improve postoperative pain and shorten hospital stay. There have been few patient reported outcomes studied in OSJ and ERAS patients. The MD Anderson Symptom Inventory (MDASI) is patient reported outcome measures used for clinical and research purposes related to cancer and its treatment. Our objective was to determine if patient reported outcomes using MDASIs are different in patients following the OSJ compared to a traditional care pathway. Methods: From July 2013 to November 2015, MDASIs were collected from 160 RC patients preoperatively and on postoperative days (POD) 1 through 3. The MDASI consists of 19 core symptom burden related questions and 6 questions analyzing how symptoms have interfered with the patient’s life. Using a 0-10 scale, patient’s rate their symptoms. T-test, Man-Whitney where appropriate and logistic regression were used for multivariable cross sectional analysis. Results: The most bothersome symptoms were abdominal discomfort, disturbed sleep, dry mouth, fatigue, and drowsiness. Nausea, vomiting, bowel pattern, bowel control and appetite were all found to be insignificant. Abdominal discomfort was reported significantly less in OSJ patients on PODs 1 and 2 (p = 0.032 and 0.001, respectively). In multivariable analysis OSJ status was predictive of less abdominal pain (p < 0.001). Dry mouth was also significantly burdensome on PODs 1 and 2 (p = 0.022 and < 0.001, respectively) in non-OSJ patients. Less dry mouth was also predicted by OSJ status in multivariable analysis (p = 0.014). Disturbed sleep, fatigue, and drowsiness were significantly less in patients on the OSJ POD 2. Mood was better in OSJ patients PODs 2 and 3 (p = 0.016). Conclusions: The OSJ can significantly reduce the burden of symptoms in RC patients immediately postoperatively. MDASIs maybe a helpful tool to measure symptom burden. This information can be used in the future to create additional interventions for improvement in RC patient recovery experiences.

Prevalence of vitamin D insufficiency and falls in older cancer patients

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Background: More than 60% of cancer patients are older adults. Such patients undergo age and cancer therapy related changes. Older adults also have geriatric risk factors for falls such as frailty, cognitive impairment (mild cognitive impairment [MCI] and dementia), and malnutrition-including vitamin D deficiency. Objective: To assess the prevalence of vitamin D insuffiency and risk factors for falls in older cancer patients. Retrospective cohort study. Methods: Patients underwent prospective data collection and retrospective analysis. Patients underwent a comprehensive geriatric assessments, including cognitive, functional, nutritional, physical, and comorbidity assessment. Vitamin D was assayed. Bone densitometry was performed. Analysis: Descriptive statistics, and multivariable logistic regression. Results: We enrolled 318 patients and 305 patients with complete data were included for final analysis. Patients were undergoing active cancer care. Patients had gastrointestinal, urologic, breast, lung and gynecologic cancers. The mean age was 78.4 ± 6.9 years. Low bone mass and osteoporosis were very common (80%) in this cohort. Twenty-six percent had one or more falls in the preceding six months. Dementia and mild cognitive impairment were seen in 33% and 37% of patients, and 53% presented frailty. In 256 patients, 48.8% (n = 125) had Vitamin D insufficiency ( < 30 ng/ml). In univariate analysis, co-morbidity (p = 0.05), frailty (p < 0.01), and cognitive impairment (0 = 0.02) were significantly associated with falls, while in multivariate analysis, frailty remained significantly associated with falls (OR = 3.51, 95%CI = 1.88, 6.52). Conclusions: Older cancer patients have a high prevalence of falls, osteoporosis and vitamin D insufficiency, raising the possibility of injurious falls (fractures). Frailty was found to be the most prominent risk factor for falls in this cohort. Greater awareness and targeted interventions such as vitamin D replacement, physical therapy, nutrition interventions, and therapy for low bone mass/osteoporosis will be effective preventing injurious falls.

Intrinsic subtypes and bladder cancer metastasis

Recent studies demonstrated that bladder cancers can be grouped into basal and luminal molecular subtypes that possess distinct biological and clinical characteristics. Basal bladder cancers express biomarkers characteristic of cancer stem cells and epithelial-to-mesenchymal transition (EMT). Patients with basal cancers tend have more advanced stage and metastatic disease at presentation. In preclinical models basal human orthotopic xenografts are also more metastatic than luminal xenografts are, and they metastasize via an EMT-dependent mechanism. However, preclinical and clinical data suggest that basal cancers are also more sensitive to neoadjuvant chemotherapy (NAC), such that most patients with basal cancers who are aggressively managed with NAC have excellent outcomes. Importantly, luminal bladder cancers can also progress to become invasive and metastatic, but they appear to do so via mechanisms that are much less dependent on EMT and may involve help from stromal cells, particularly cancer-associated fibroblasts (CAFs). Although patients with luminal cancers do not appear to derive much clinical benefit from NAC, the luminal tumors that are infiltrated with stromal cells appear to be sensitive to anti-PDL1 antibodies and possibly other immune checkpoint inhibitors. Therefore, neoadjuvant and/or adjuvant immunotherapy may be the most effective approach in treating patients with advanced or metastatic infiltrated luminal bladder cancers.

Abstract 816: Genetic variants in the dopaminergic system and bladder cancer clinical outcomes

Bladder cancer is estimated to be the fourth most common cancer diagnosed and the eighth most common cancer related death in men in 2015. A hallmark of bladder cancer outcomes is the high rates of recurrence and progression in patients diagnosed with non-muscle invasive bladder cancer (NMIBC) and poor survival rates in those that have progressed to or are diagnosed with muscle invasive bladder cancer (MIBC). Because of the poor outcomes, research for predictors of clinical outcomes is necessary. Recent studies show that current depressive symptoms at time of bladder cancer diagnosis are associated with bladder cancer mortality. We are interested in investigating the genetic mechanism underlying this relationship. The dopaminergic pathway is of interest because of its associations with depression and smoking addiction (with smoking being the main risk factor for bladder cancer). Therefore we aimed to do a candidate pathway analysis examining 256 single nucleotide polymorphisms (SNPs) in 15 genes from the dopaminergic system. We analyzed the association of genetic variants with recurrence and progression in NMIBC patients (N = 497) and the association with survival in MIBC patients (N = 399). Overall, there were four SNPs with a p-value of less than 0.01associated with recurrence in NMIBC. The most significant variant being rs2797853 located in DBH under the recessive model (HR = 1.77, 95% CI: 1.28- 2.46. P = 0.0012). Eight polymorphisms had a statistically significant association with progression in NMIBC patients, with COMT: rs5993891 being the most significant variant showing an increased odds of bladder cancer progression (HR = 2.54, 95% CI: 1.50- 4.28, P = 0.0013). Interestingly, the variant rs174675 located in COMT (an enzyme responsible for degrading dopamine) was associated with an increased risk of recurrence (HR = 1.23, 95% CI: 1.01-1.49, P = 0.046) and progression (HR = 1.55, 95% CI: 1.13-2.12, P = 0.007). Finally, five SNPs were statistically significant for bladder cancer survival in MIBC patients. BDNF: rs2203877 was associated with a 71% increased risk of death (HR = 1.71, 95% CI: 1.25-2.34, P = 0.001). There was a significant difference in median survival time (MST). Those with the homozygous dominant or heterozygous genotype had a MST of 66.3 months and those with the homozygous recessive genotype had a MST of 31.8 months (Plog-rank = 0.02). The variant rs2239395 in COMT was associated with an increased risk of progression (HR = 2.54, 95% CI: 1.49-4.34, P = 0.002) and death (HR = 1.63, 95% CI: 1.05-2.53, P = 0.041). In addition to validation studies that are underway, the next steps include analyzing the association between these factors and BMI (a factor associated with depression, the dopamine system, and bladder cancer). The results of this study have the potential to contribute to identifying bladder cancer patients who may have poor clinical outcomes as well as the development of interventions that may improve outcomes.

Citation Format: Jeanne A. Pierzynski, Yuanquing Ye, Alma Rodriguez, Michelle A.T. Hildebrandt, Ashish M. Kamat, Colin P.N. Dinney, Xifeng Wu. Genetic variants in the dopaminergic system and bladder cancer clinical outcomes. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 816.

A STAT3- and p63-dependent transcriptional network to define a lethal basal subset of human bladder cancers

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Background: Muscle-invasive bladder cancers (MIBCs) are a heterogeneous group of tumors that display widely variable clinical outcomes and responses to conventional chemotherapy. Methods: We used whole genome mRNA expression profiling and unsupervised hierarchical cluster analyses on a cohort of 73 flash frozen primary tumors to identify 3 distinct subsets of muscle-invasive bladder cancer (MIBC). We confirmed the existence of these 3 subsets in a second cohort of 57 formalin-fixed, paraffin-embedded (FFPE) MIBCs and in 2 other public datasets. Analysis of primary tumors and mechanistic studies in human bladder cancer cell lines identified tumors that respond to FGFR inhibitors or chemotherapy. Results: The first subset was driven by an active "basal" EGFR-STAT3-p63 transcriptional network, and was associated with poor clinical outcomes. High miR-200c expression stratified the survival of these basal tumors. The second subset was characterized by active p53 pathway activation, and tumors and cell lines with these features were resistant to cis-platinum based chemotherapy. The third subset expressed "luminal" markers and active estrogen receptor (ER) and PPARγ signaling, and luminal cell lines were sensitive to fibroblast growth factor receptor (FGFR) inhibition. Conclusions: Molecular subtyping of MIBCs can be used to identify lethal cancers and enrich for tumors that will respond to FGFR inhibitors or conventional chemotherapy.