Citations

563 Background: Clinical trials mRCC pts are different from real world pts, resulting in bias in the literature. The MaRCC Registry is designed to survey questions not asked in tri als, such as why physicians make certain management decisions. This analysis describes reasons for physician treatment (tx) selection in the first 109 real world pts enrolled in a multicenter, prospective, observational registry. Methods: MaRCC Registry will enroll 500 pts from up to 60 US academic (ACAD) and community (COMM) sites with ~2 years of recruitment and ≥ 3 years of follow-up. Key inclusion criteria are age ≥ 18 years and diagnosis of mRCC with no prior systemic therapy (STx) for mRCC at study entry. Pts currently not on STx but who are being observed are permitted. Key endpoints include descriptive characteristics of txs, tx and patient outcomes, medication adherence, and health resource utilization. Results: At data cutoff, 105 pts have been accrued with known STx status; median age 64 (Q1-3 range, 56-70); 66% male; 75% ACAD; 87% clear cell histology; and 31% stage IV at diagnosis. Initial management decision was: 40% deferred systemic therapy (DSTx), 22% pazopanib, 18% clinical trial, 10% sunitinib, and 6% other. Among STx pts (N = 61), the most common categories for therapy choice as selected by providers were likelihood of clinical benefit (41%) followed by pt characteristics (30%). Within the clinical benefit category, the most common reason was OS/PFS (31%). Within the pt characteristic category the most common reasons included performance status/frailty (12%) or prognostic factors (12%). Common reasons for DSTx pts (N = 44) were active surveillance (AS) with disease present (39%), AS without disease present following a procedure (11%), or local therapy (7%). ACAD sites had higher percentages of pts with DSTx undergoing AS with disease present and local therapy. Conclusions: This is the first report describing factors driving physician decision making in management of mRCC. Management choices are not captured in other prospective or retrospective studies. Early experience suggests that clinical benefit and pt characteristics were common reasons for initial STx. Side effect profile rarely determined initial STx selection.

536 Background: DNA methylation is a heritable covalent modification that is developmentally regulated and is critical in tissue-type definition. Although genotype-phenotype correlations have been described for different subtypes of renal cell carcinoma (RCC), it is unknown if DNA methylation profiles correlate with morphological or ontology based phenotypes. Here we test the hypothesis that DNA methylation signatures can discriminate between putative precursor cells in the nephron. Methods: We performed deep profiling of DNA methylation in diverse histopathological RCC subtypes and validated DNA methylation and transcriptome signatures in The Cancer Genome Atlas Clear Cell and Chromophobe Renal Cell Carcinoma Datasets. Results: Our data provide the first mapping of methylome epi-signature and indicates that RCC subtypes can be grouped into two major epi-clusters: C1 which encompasses clear cell RCC, papillary RCC, mucinous and spindle cell carcinomas and translocation RCC; C2 which comprises oncocytoma and chromophobe RCC. Interestingly, C1 epi-cluster displayed three fold more hypermethylation as compared to C2 epi-cluster. Of note, differentially methylated regions between C1 and C2 epi-clusters occur in gene bodies and intergenic regions, instead of gene promoters. Transcriptome analysis of C1 epi-cluster suggests a functional convergence on Polycomb targets, whereas C2 epi-cluster displays DNA methylation defects. Furthermore, we find that our epigenetic ontogeny signature is associated with worse outcomes of patients with clear-cell RCC. Conclusions: Taken together, our data defines the epi-clusters that can discriminate between distinct RCC subtypes and for the first time, to our knowledge, define the epigenetic basis for proximal versus distal tubule derived kidney tumors.

513 Background: Chromophobe renal cell carcinoma (chRCC) is the third most common histologic subtype of kidney cancer. While most of these tumors have an indolent behavior, 7% of patients with chRCC develop metastases, with no currently available standard of care. The Cancer Genome Atlas characterized chRCC, highlighting pathognomonic single copy chromosomal losses of 1, 2, 6, 10, 13 and 17, as well as a minimal mutation burden distinguishing it from all other cancer types. However, only 15% of the analyzed patients had advanced disease. We analyzed metastatic chRCC to further characterize these tumors and elucidate mechanisms leading to aggressive disease using a variety of next generation and whole genome sequencing. Methods: Our cohort of metastatic chRCC consisted of 40 patients with available clinical and pathologic data. Whole genome sequencing (WGS) was performed on 6 patients (4 primary tumors and 2 metastases), 42 additional samples from 33 patients were analyzed using targeted next-generation sequencing (MSK-IMPACT). Notably, we were able to collect and analyze matched primary and metastatic tumors from 7 patients. As control cohort 27 non-metastatic chRCC tumors were sequenced with MSK-IMPACT. Copy number patterns were computed with OncoSNP seq and FACETS. Results: The most commonly mutated genes in the aggressive chRCC tumors were TP53 and PTEN (WGS: TP53 67 %, PTEN 33%; MSK-IMPACT: TP53 61%, PTEN 27%). No other genes were mutated frequently. Primary tumor samples of chRCC did show the typical pattern of chromosomal losses in 1, 2, 6, 10, 13 and 17. Interestingly, these canonical losses could not be detected in the metastases even when accounting for tumor purity. Conclusions: TP53 and PTEN mutations are highly enriched in both primary and metastatic tumors of aggressive chRCC compared to the non-aggressive tumors and likely play a critical role in disease progression. More intriguingly, the observation of differential copy numbers in matched primary and metastatic tumors suggest whole genome or whole chromosome events in these samples. We are currently employing different bioinformatic and cytogenetic platforms to validate our novel hypothesis of chromosomal events as driver for metastatic development in chRCC.

501 Background: Reports have demonstrated an inverse relationship between suppression of immune surveillance mechanisms and activation of the vascular endothelial growth factor receptor (VEGFR) pathway suggesting that T cell repertoires may impact response to VEGFR blockade. We evaluated the association between clinical outcomes and T cell repertoire in metastatic RCC patients receiving a front-line anti-VEGFR, pazopanib. Methods: Pre-treatment RCC tumors were analyzed from VEG105192, a phase III study of mRCC patients randomized (2:1) to pazopanib (paz) 800 mg daily vs placebo (pbo) for TCR gamma (TCRG) and TCR beta (TCRB) CDR3 regions. Using the Adaptive Biotechnologies immunoSEQ Assay, we assessed TCR clonality, a measure of total repertoire represented by expanded clones, and entropy, a measure of evenness and diversity. PD-L1 was evaluated by immunohistochemistry (IHC) H-Scores. The goal of the study was to determine if the repertoire of T cell clones was associated with progression-free survival as a clinical endpoint. Results: In the cohort with available tissue, the median PFS was 10.8 and 5.5 months (mos) for paz and pbo, respectively. TCRB (n = 114) and TCRG (n = 43 pbo, 109 paz) clonality ranged from 0-0.31 and 0-0.98, and entropy from 1-12.1 and 0-10.37, respectively. TCRB and TCRG entropy were highly correlated (Spearman’s R = 0.92, n = 114). Samples from the pbo-treated group with higher TCRG entropy, defined as the top 25th percentile, were associated with an improved median PFS (12.8 months) when compared to the lower 75th percentile (3.1 months, P = 0.023); similar trends were seen for TCRB entropy. Neither entropy nor clonality was associated with maximal reduction in tumor volume in the paz-treated group. PD-L1 H-scores were not associated with entropy or clonality (P > 0.05). Conclusions: Our data suggests that RCC samples with higher entropy are associated with a favorable prognosis. Identification of tumors with restricted TCRB/G chain usage and less diverse repertoire, as represented by lower entropy and higher clonality, may impact responses to VEGFR blockade and requires further study. Clinical trial information: NCT00334282.

471 Background: Urine based assays that can non-invasively detect bladder cancer (BCa) have the potential to reduce unnecessary and invasive procedures. The purpose of this study was to develop a multiplex immunoassay that can accurately and simultaneously monitor 10 diagnostic urinary protein biomarkers for application as a non-invasive test for BCa detection Methods: A custom electrochemiluminescent (ECL) multiplex assay was constructed (Meso Scale Diagnostics, LLC, Rockville, MD) to detect the following urinary proteins; IL8, MMP9, MMP10, ANG, APOE, SDC1, A1AT, PAI1, CA9 and VEGFA. Voided urine samples from two cohorts (cohort #1 n = 62 and cohort #2 n = 200) were collected prior to cystoscopy and samples were analyzed blinded to the clinical status of the participants. Means (±SD) and receiver operating characteristic (ROC) curve analysis were used to compare assay performance and to assess the diagnostic accuracy of the diagnostic signature. Results: Comparative diagnostic performance analyses revealed an AUROC value of 0.9258 for the multiplex assay and 0.9467 for the combination of the single-target ELISA assays (p = 0.625), so there was no loss of diagnostic utility for the MSD multiplex assay. Analysis of the independent 200-sample cohort using the multiplex assay achieved an overall diagnostic sensitivity of 0.85, specificity of 0.81, positive predictive value 0.82 and negative predictive value 0.84. Conclusions: It is technically feasible to simultaneously monitor complex urinary diagnostic signatures in a single assay without loss of performance. The described protein-based assay has the potential to be developed for the non-invasive detection of BCa.

445 Background: Radical cystectomy (RC) is the gold standard treatment for muscle-invasive and high-risk non-muscle invasive bladder cancer. However, the procedure has been associated with a high complication rate, including perioperative infection. In addition to resulting in patient morbidity, infections have been suggested as a quality metric. We sought to evaluate the incidence, risk factors, and timing of infection following RC. Methods: The National Surgical Quality Improvement Program (NSQIP) database was queried to identify patients undergoing RC for bladder cancer from 2005-2013 using CPT procedure and ICD-9 diagnosis codes. Infections (urinary tract infection (UTI), surgical site infection (SSI), and sepsis) within 30 days of RC were recorded. Characteristics including age, gender, ethnicity, body-mass index, diabetes, smoking status, renal function, steroid usage, albumin, receipt of perioperative transfusion, and operative time were abstracted, and relative risk of infection was assessed in univariate chi-squared analysis. Results: A total of 3,187 patients were identified, of whom 2604 (81.8%) were male, with a median age of 68.8 years (IQR 62, 77). Postoperative infection was diagnosed in 766 (24%) patients, at a median of 13 days (IQR 8, 19) after RC, with 44.4% occurring prior to hospital discharge. The most common type of infection was SSI (404; 12.7%), followed by sepsis (315; 9.9%), and UTI (309; 9.7%). Factors associated with increased overall infection risk were obesity (RR 1.32; 1.20-1.46; p < 0.001), receipt of a blood transfusion (RR 1.20; 1.10-1.31; p < 0.001), and increased operative time (RR for > 450 min 1.46; 1.26-1.70; p < 0.001). Risk factors for UTI in particular included obesity (RR 1.28; 1.11-1.47; p < 0.001), diabetes (RR 1.38; 1.09-1.75; p = 0.009), and increased operative time (RR for > 450 min 1.45; 1.18-1.78; p < 0.001). Conclusions: Approximately 25% of patients undergoing RC experience an infection within 30 days of surgery, most commonly SSI. Several modifiable risk factors were identified, including blood transfusion and prolonged operative time, that represent potential targets for care improvement.

4 Background: Management of patients with a postoperative rising prostate-specific antigen (PSA) level is complex. Additional local treatment such as salvage radiation therapy (SRT) may be sufficient for many patients but some may require concurrent systemic therapy in order to delay or prevent metastatic disease. As PSA recurrence on its own is a poor surrogate for metastatic disease we hypothesized that the Decipher genomic classifier (GC), a validated predictor of metastasis may be able to better distinguish those patients where additional therapy is beneficial from those where SRT on its own is likely sufficient. Methods: Genomic classifier (GC) scores were calculated from 170 prostate cancer patients, who received SRT at the Veteran Affairs Medical Center Durham, Thomas Jefferson University and Mayo Clinic, between 1990 and 2010. SRT was defined as administration of RT with Pre-RT PSA levels > 0.2 ng/ml. GC and CAPRA-S scores were compared using survival c-index, competing-risks and Cox regression analysis for the prediction of metastasis. Results: Survival c-index for predicting metastasis 5 years post SRT was 0.85 (95% CI: 0.73-0.88) for GC and 0.63 (95% CI: 0.49-0.77) for CAPRA-S. The cumulative incidence of metastasis at 5 years post-SRT was 2.7%, 8.4%, and 33.1% for low, average, and high GC scores (p < 0.001) and 16.9%, 2.3% and 17.2% for low, average and high CAPRA-S scores (p = 0.113). In univariable analysis only GC, extraprostatic extension, path GS and Pre-RT PSA were significant predictors of metastasis. In multivariable analyses with clinical risk factors or the CAPRA-S risk model, GC was the only independent predictor of metastasis with a HR of 1.63 (1.22-2.18, p < 0.001) for a 10% unit increase in risk score. Conclusions: In patients treated with postoperative SRT for PSA recurrence, GC is a powerful predictor of metastasis. Patients with low Decipher have excellent prognosis with SRT and may avoid concurrent hormonal therapy. Patients with high Decipher risk are at highest risk for metastatic disease and SRT failure and may benefit from intensified systemic therapy.

389 Background: Venous thromboembolism (VTE) has been reported in approximately 5-7% of patients undergoing radical cystectomy (RC). While extended-duration pharmacologic prophylaxis (EDPP) has been investigated following surgery for a variety of malignancies, limited data exist in bladder cancer. Herein, we evaluated the efficacy and safety of EDPP after RC. Methods: We instituted a change in our clinical practice beginning in May 2014 such that patients undergoing RC were prescribed 30 days of enoxaparin at discharge. We recorded symptomatic VTE and lymphocele rates within 30 days of RC among patients treated from 5/14-6/15, and compared these outcomes to the cohort of all patients who underwent RC at our institution in the year prior to EDPP implementation. Patients in both groups received subcutaneous unfractionated heparin and mechanical prophylaxis during hospitalization. Patients with a history of VTE prior to surgery (n = 24) were excluded from study. Unadjusted descriptive statistics and univariate analyses were performed using the Pearson or Fisher chi-square test for categorical variables and Wilcoxon rank-sum test for continuous variables. Results: In total, 58 patients who received EDPP and 82 patients who had not received EDPP after RC were included for analysis. Baseline clinicopathologic demographics were similar between the cohorts. We found that only 1 patient (1.9%) discharged with EDPP was diagnosed with a VTE within 30 days of RC, compared to 5 (6.1%) who had not received EDPP. Mean time to VTE was 18.0 days after RC (range 9-28 days). Events consisted of DVT alone (n = 2), DVT and PE (n = 2), and PE alone (n = 2). The odds ratio for VTE in the absence of EDPP was 3.31 (95% CI 0.38, 29.2). Overall, 3 patients developed a symptomatic lymphocele within 30 days of RC: 1 (1.9%) who received EDPP and 2 (2.4%) who had not (p = 0.84). No patient in either cohort was rehospitalized for bleeding complications. Conclusions: Our initial experience suggests that EDPP was associated with a lower rate of VTE following RC, and does not increase the risks of bleeding or symptomatic lymphocele. Future evaluation in a larger-scale prospective clinical trial setting is needed to confirm the benefit of EDPP in RC patients.

353 Background: One mechanism leading to castrate-resistant prostate cancer (CRPC) is upregulation of CYP17. Abiraterone acetate (AA) inhibits CYP17 and continuous AA administration (CAAA) is one the most common and effective CRPC treatments. Mathematical models can be potentially powerful clinical tools for optimizing treatment strategies and eliminating guess work. Here, we introduce a new model which builds on our previous work (Morken JD, Packer A, Everett RA, Nagy JD, Kuang Y. Mechanisms of resistance to intermittent androgen deprivation therapy identified in prostate cancer patients by novel computational method. Cancer Res 2014;74:2673-83.) and may be capable of predicting how patients will respond to CAAA and intermittent AA administration (IAAA). We are currently proposing a personalized IAAA protocol on the basis of these results. Methods: In this ongoing retrospective study, we use PSA data from patients whom underwent CAAA to validate the accuracy of our model of tumor growth and evolution. The PSA output is driven by dynamics of three cell populations—castration-sensitive (CS), castration-resistant abiraterone-sensitive (CSAS), and castration-sensitive abiraterone-resistant (CSAR) cells. We fit the model output to PSA data to find parameter values which minimize normalized mean squared error (NMSE). Once parameters are obtained, we ran simulations employing various IAAA protocols. Results: The model’s PSA dynamics are highly accurate. NMSE is very low across patients ranging from 0.0001-0.0085. Conclusions: Our results suggest that there exists an IAAA protocol for each patient that, at worst, yields the same time to tumor progression as CAAA, yet improves quality of life and reduces cost. In nearly 20% of patients, IAAA appears to delay tumor progression over CAAA. The model is accurate at predicting how patients will respond to CAAA and IAAA for patients whose PSA is regularly monitored. Near-future work aims to personalize IAAA protocol based on patient pre CRPC PSA dynamics and to identify a protocol which delays progression for most patients.

313 Background: We evaluated variation in candidate genes implicated in either initiation or progression of prostate cancer with survival in CRPC stage. Methods: Germline DNA was extracted from peripheral blood mononuclear cells of CRPC patients enrolled in a clinically annotated registry. Fourteen candidate genes were tagged using single nucleotide polymorphisms (SNPs) from HapMap with minor allele frequency of > 5%. The primary endpoint was overall survival (OS), defined as time from development of CRPC to death. Principal component analysis was used for gene levels tests of significance. For SNP level results the per allele hazard ratios (HR) and 95% confidence intervals (CI) under the additive allele model using Cox regression adjusted for age at CRCP and Gleason score (GS) were used. Results: Two hundred and forty five CRPC patients who met the criteria of having adequate DNA were genotyped (14 genes, 84 SNPs). The median age of the cohort was 69 years (range 43-93). The GS distribution was 55% with GS≥8, 32% with GS = 7 and 13% with GS < 7 or unknown. Median time from castration resistance to death for the cohort was 2.67 years (IQ range: 1.6-4.07, 144 deaths). At the gene level JAK2 was detected to be associated with OS. Six of 18 JAK2 SNPs were associated with OS after adjustment for age and GS as well as pruning of SNPs in high linkage disequilibrium with each other (see table). In our multivariate model including age, GS, rs2149556, and rs4372063, the adjusted HRs for rs2149556 and rs4372063 were 0.67 (95% CI 0.38-1.18) and 2.17 (95% CI 1.25-3.76), respectively. The protective effect of rs2149556 appears after adjusting for the presence of minor alleles for rs4372063 in this dataset. Conclusions: Germline variation in the JAK2gene is associated with survival in CRPC stage and warrants further validation as a potential prognostic biomarker. [Table: see text]