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Background: Nonrheumatic valvular diseases are common; however, no studies have estimated their global or national burden. As part of the Global Burden of Disease Study 2017, mortality, prevalence, and disability-adjusted life-years (DALYs) for calcific aortic valve disease (CAVD), degenerative mitral valve disease, and other nonrheumatic valvular diseases were estimated for 195 countries and territories from 1990 to 2017. Methods: Vital registration data, epidemiologic survey data, and administrative hospital data were used to estimate disease burden using the Global Burden of Disease Study modeling framework, which ensures comparability across locations. Geospatial statistical methods were used to estimate disease for all countries, because data on nonrheumatic valvular diseases are extremely limited for some regions of the world, such as Sub-Saharan Africa and South Asia. Results accounted for estimated level of disease severity as well as the estimated availability of valve repair or replacement procedures. DALYs and other measures of health-related burden were generated for both sexes and each 5-year age group, location, and year from 1990 to 2017. Results: Globally, CAVD and degenerative mitral valve disease caused 102 700 (95% uncertainty interval [UI], 82 700–107 900) and 35 700 (95% UI, 30 500–42 500) deaths, and 12.6 million (95% UI, 11.4 million–13.8 million) and 18.1 million (95% UI, 17.6 million–18.6 million) prevalent cases existed in 2017, respectively. A total of 2.5 million (95% UI, 2.3 million–2.8 million) DALYs were estimated as caused by nonrheumatic valvular diseases globally, representing 0.10% (95% UI, 0.09%–0.11%) of total lost health from all diseases in 2017. The number of DALYs increased for CAVD and degenerative mitral valve disease between 1990 and 2017 by 101% (95% UI, 79%–117%) and 35% (95% UI, 23%–47%), respectively. There is significant geographic variation in the prevalence, mortality rate, and overall burden of these diseases, with highest age-standardized DALY rates of CAVD estimated for high-income countries. Conclusions: These global and national estimates demonstrate that CAVD and degenerative mitral valve disease are important causes of disease burden among older adults. Efforts to clarify modifiable risk factors and improve access to valve interventions are necessary if progress is to be made toward reducing, and eventually eliminating, the burden of these highly treatable diseases.

Left bundle branch block may be due to conduction system degeneration or a reflection of myocardial pathology. Left bundle branch block may also develop following aortic valve disease or cardiac procedures. Patients with heart failure with reduced ejection fraction and left bundle branch block may respond positively to cardiac resynchronization therapy. Lead placement via the coronary sinus is the mainstay approach of cardiac resynchronization therapy. However, other options, including physiological pacing, are being explored. In this review, we summarize the salient pathophysiologic and clinical aspects of left bundle branch block, as well as current and future strategies for management.

Vascular abnormalities are the most important non-cystic complications in Polycystic Kidney Disease (PKD) and contribute to renal disease progression. Endothelial dysfunction and oxidative stress are evident in patients with ADPKD, preserved renal function, and controlled hypertension. The underlying biological mechanisms remain unknown. We hypothesized that in early ADPKD, the reactive oxygen species (ROS)-producing nicotinamide adenine dinucleotide phosphate hydrogen (NAD(P)H)-oxidase complex-4 (NOX4), a major source of ROS in renal tubular epithelial cells (TECs) and endothelial cells (ECs), induces EC mitochondrial abnormalities, contributing to endothelial dysfunction, vascular abnormalities, and renal disease progression. Renal oxidative stress, mitochondrial morphology (electron microscopy), and NOX4 expression were assessed in 4- and 12-week-old PCK and Sprague-Dawley (wild-type, WT) control rats (n = 8 males and 8 females each). Endothelial function was assessed by renal expression of endothelial nitric oxide synthase (eNOS). Peritubular capillaries were counted in hematoxylin–eosin (H&E)-stained slides and correlated with the cystic index. The enlarged cystic kidneys of PCK rats exhibited significant accumulation of 8-hydroxyguanosine (8-OHdG) as early as 4 weeks of age, which became more pronounced at 12 weeks. Mitochondria of TECs lining cysts and ECs exhibited loss of cristae but remained preserved in non-cystic TECs. Renal expression of NOX4 was upregulated in TECs and ECs of PCK rats at 4 weeks of age and further increased at 12 weeks. Contrarily, eNOS immunoreactivity was lower in PCK vs. WT rats at 4 weeks and further decreased at 12 weeks. The peritubular capillary index was lower in PCK vs. WT rats at 12 weeks and correlated inversely with the cystic index. Early PKD is associated with NOX4-induced oxidative stress and mitochondrial abnormalities predominantly in ECs and TECs lining cysts. Endothelial dysfunction precedes capillary loss, and the latter correlates with worsening of renal disease. These observations position NOX4 and EC mitochondria as potential therapeutic targets in PKD.

11574 Background: Weight gain after cancer diagnosis is common in cancer survivors and has been linked to increased treatment toxicity, poor quality of life, and increased risk of second cancers and overall mortality. Young breast cancer (BC) survivors may be especially susceptible to weight changes given the impact of treatments such as chemotherapy and hormonal therapy on menopausal status. Methods: We identified women with Stage 0-III breast cancer diagnosed at ≤40 years (y) between 2006-2016 from a multi-center prospective cohort study. Clinical data including self-reported pre-diagnosis and follow-up weights were obtained using baseline and follow-up patient surveys. Participants missing baseline weight, pregnant at diagnosis/within 1y of diagnosis or with BC recurrence within 1y were excluded; those pregnant or with BC recurrence between 1-3y from diagnosis were excluded from the 3y analysis. Menopausal status at baseline and treatment-related amenorrhea (TRA) in follow-up were defined by self-reported last menstrual period. Factors associated with weight gain (>5%) were evaluated using univariate two-sided Fisher's exact test. Results: At baseline, 1y and 3y post diagnosis, 956, 899 and 687 women were eligible for analysis respectively. Median age at diagnosis was 37y (17 - 40), 65% received endocrine therapy and 74% chemotherapy. Premenopausal status was verified in 94% at baseline. Mean BMI at baseline was 24.4 (SD 5.3) kg/m2; 20% (187/956) were overweight and 12% (116/956) obese. At 1y and 3y, mean BMI increased modestly to 24.7 (SD 5.6) and 24.9 (SD 5.2), respectively with weight gain (>5%) observed in 18% (164/899) and 13% (87/687) respectively. 37% (300/804) and 32% (196/615) of eligible premenopausal subjects experienced TRA at 1y and 3y, respectively. Receipt of chemotherapy, receipt of endocrine therapy and TRA were not associated with weight gain at any timepoint. Conclusions: In this large prospective cohort of young BC survivors, mean BMI increased only modestly over time. Self-reported weight gain was not associated with treatment and not exacerbated by TRA. Further analysis to understand the effects of physical activity and other predictors of weight gain in this population are ongoing.

7545 Background: Interpretation of lung cancer clinical trials is complicated by the heterogeneity of the patient population due to disease burden and comorbidities making pre-trial assessment of OS probability challenging. Methods: To create and validate a scoring system to estimate OS and improve the quality of future trials, this study evaluated the pretreatment prognostic factors of 2,442 pts with NSCLC. Univariate (UV) and multivariate (MV) Cox models were used to evaluate the prognostic importance of each baseline factor on OS. Those prognostic factors significant on both UV and MV analyses that were used to develop the scoring system included overall quality of life, age, sex, stage, ECOG performance status, the presence of other cancers, and smoking cessation. The score for each factor was determined by dividing the 5-year OS rate (in %) by 10 and summing these scores to form a total score. Multivariate models and the score for each factor were validated using bootstrapping with 1000 iterations from the original samples. Results: The score for each factor ranged from 1 to 7 points and the total scores ranged between 23 and 39 points. Higher scores reflected better OS. Categorization of the score was delineated first by clinician expert opinion (see Table) and then by multiple statistically defined empirical cut points. All categorization schemes demonstrated successful prognostic power. The bootstrap method confirmed the reliability of multivariate Cox model and score (Spearman correlation coefficient= 0.45). Conclusions: Prognostic factors significantly associated with OS on both UV and MV analysis were used to construct a valid scoring system which can be used to predict survival of NSCLC pts. This scoring system can be used by clinicians in counseling pts and for stratification in future trial design. [Table: see text]

7524 Background: A multicenter study (Z4032) compared sublobar resection (SR) to sublobar resection with brachytherapy (SRB) for stage I NSCLC. Local recurrence (LR) and overall survival (OS) rates at 3-years (3-yr) were similar between arms (see abstract 113613). This analysis combines arms, and evaluates the effect of factors previously reported to impact oncological outcomes after SR. Methods: 213 patients (pts) were evaluable for analysis. LR was defined as recurrence at the staple line (local progression), same lobe away from the staple line, or within hilar nodes. Factors assessed for impact on 3-yr outcomes were: resection type (wedge/segmentectomy), margin size (<1cm /≥1cm), margin:tumor ratio (<1/ ≥1), tumor size (≤2cm/>2cm) and staple line cytology (+/-). Results: LR occurred in 27/213 (12.6%) pts and included local progression in 12/213 (5.6%). OS rate at 3-yr was 152/213 (71.4%). Trends favored the use of segmentectomy, margin:tumor ratio≥1, tumor size ≤2cm and negative staple line cytology; no factor reached statistical significance at 3-yr. The only factor significantly (p=0.02) associated with decreased 3-yr LR was margin size ≥1cm (8.3%) compared to margin<1cm (19.3%). Conclusions: SR is a good option for high-risk pts with NSCLC. The 3-yr OS rate of 71.4% and local progression rate of 5.6% are useful benchmarks to compare to other therapies. A resection margin of at least 1 cm is desirable. Clinical trial information: NCT00107172. [Table: see text]

e17017 Background: Epigenetic up-regulation of EBV and cellular genes via demethylation and histone deacetylase inhibition can induce EBV lytic replication enhancing immune mediated tumor killing and up-regulation of tumor suppressor genes resulting in tumor apoptosis. Methods: Patients (Pt) with relapsed or refractory NPC and NK-T cell lymphomas were enrolled to determine safety, tolerability, pharmacokinetics (PK), pharmacodynamics and preliminary anti-tumor activity using a dose escalation design. 5AC was administered on days 1 to 10 sub-cutaneously while SAHA was administered on days 1 to 14 orally. PK for SAHA, EBV viral load, characterization of circulating EBV, Immunohistochemistry (IHC) and EBV promoter methylation analysis in tumor tissue were performed. Results: 11 pt have been treated (M:F 8:3, median age 48, R: 35-71) at 3 dose levels – 5AC 50 mg/m2 and SAHA 200 mg b.i.d. (dose level 1), 5AC 37.5 mg/m2 and SAHA 200 mg q. am and 100 mg q. pm (dose level 2), and 5AC 25 mg/m2 and SAHA 100 mg b.i.d (dose level 3). Median number of previous treatment regimens was 3 (R:1-6). Dose limiting toxicities (DLT) were seen in 2/2 pts at dose level 1: grade 4 thrombocytopenia (1 pt), grade 3 nausea, vomiting and fatigue (2 pts), and grade 5 hepatic failure (1 pt). Two of six patients at dose level 2 experienced DLT: grade 3 fatigue (1 pt) and worsening of pre-existing Sweet’s Syndrome (1 pt). Common AEs (G1/2) included fatigue (73%), cough (64%), anorexia (55%), and injection site reaction (45%). One minor response was seen and 5 pt had prolonged stable disease (>16 weeks), including one patient for 88 weeks. Analysis of post-treatment tumor biopsies showed demethylation of EBV lytic cycle gene promoters after treatment. SAHA PK, IHC results for EBV gene expression in tumor tissue, EBV viral load and characterization of circulating EBV will be presented. Conclusions: 5AC/SAHA appears to be tolerable at dose level 3 with suggestion of clinical benefit. Analysis of post-treatment tumor and blood samples suggests that modulation of EBV gene expression may play a role in the mechanism underlying clinical benefit. Continued accrual at dose level 3 is ongoing. Clinical trial information: NCT00336063.

5082 Background: We evaluated the association of germ-line variation in 10 candidate genes important in prostate cancer biology (NKX3-1, JAK2, SLCO2B1, STAT3, CYP19A1, HSD17B4, TRMT11, PRMT3, HSD17B12, NCOA4) with failure of AA in advanced prostate cancer patients. Methods: Patients (N=619) were enrolled for genotyping at the time of AA failure. Candidate genes were selected from the literature and previous pilot studies in smaller cohorts which had identified variation in TRMT11 and HSD17B12 to be associated with AA failure. Genes were tagged using single nucleotide polymorphisms (SNPs) from HapMap with minor allele frequency of >5% and r2≥0.8. DNA was extracted from peripheral blood and genotyped using Illumina Veracode platform. The primary endpoint was time to failure on AA, defined as time from initiating continuous AA to two serial PSA increases over the nadir or clinical or imaging based progression, whichever came first. Principal component analysis was used for gene-levels tests. Association with the primary endpoint was assessed using proportional hazards regression models at the gene-level and at the SNP level. For SNP level results we estimated per allele (ordinal model) hazard ratios (HR) and 95% confidence intervals (CI) using Cox regression, adjusted for Gleason score (GS). Results: We successfully genotyped 60 SNPs (from 10 genes) in 519 subjects. The median age of the cohort was 71 years (range 43, 92). The GS distribution was 51% subjects with GS≥8; 33% with GS=7 and 17% with GS<7. Median time to AA failure for the cohort was 2.3 years (IQ range: 1.0-4.5). In gene level analyses adjusting for GS, TRMT11 (p=0.004), HSD17B12 (p=0.016), and JAK2 (p=0.044) genes were associated with time to AA failure. Four of the 18 genotyped SNPs in JAK2 were associated with AA failure after adjustment for GS (Table). Conclusions: Variation in the JAK2 gene is significantly associated with time to AA failure. Validation is needed to develop these as predictive biomarkers for AA in advanced prostate cancer. [Table: see text]

e14507 Background: Regorafenib, an oral multikinase inhibitor of VEGFR2/3, PDGFRb, KIT, FGFR, RET, RAF and TIE2, is efficacious in refractory mCRC but its mechanism of action is unclear and predictive biomarkers are lacking. Methods: We assessed tumor and circulatory biomarkers in a phase 2 study of regorafenib in refractory mCRC patients. Regorafenib was administered orally at 160mg/d for 3 out of 4 weeks. Post cycle 2 response was assessed by RECIST 1.1. Subjects were scheduled for FDG PET-CT scans (pre + D15) and paired core needle tumor biopsies for IHC analysis (pre + D21) in cycle 1. Archival tumor mutations were evaluated using Sequenom MassARRAY OncoCarta Panel V1.0 assay. Results: 35 patients were treated; 49% received > 4 prior therapies and 43% had prior bevacizumab. Median PFS was 3.45 mths (95% CI: 3.40-3.49), ORR was 3% and disease control rate [DCR] (PR + SD at 8 wks) was 57%. Early PET responses (EORTC criteria) were seen in 49%, but did not predict for DCR (p=1.0). Fatigue, hand foot skin reaction (HFSR), voice change and diarrhea occurred in > 30% of subjects. Grade 3-5 toxicities occurred in 46%, the commonest being HFSR and rash (17% each). Median relative dose intensity was 92%; 43% required > 1 dose reduction, 60% required > 1 dose interruption. KRAS (29%), BRAF (9%), EGFR (9%), NRAS (6%) KIT (3%), PIK3CA (3%), PDGFRA (3%) and CDK (3%) mutations were detected in archival tumors. None predicted for ORR or DCR; PFS was identical in KRAS mutant vs wt patients (3.45 mths, p=0.39) and similar in BRAF mutant vs wt patients (3.48 vs 3.45 mths, p=0.10). The patient with the longest PFS (12.6 mths) had a BRAF mutation. Amongst the 10 paired tumor samples available, IHC markers upregulated in >50% cases were pMEK, pERK, pJun and pJNK, whilst those downregulated/ unchanged in >50% were pKIT, pVEGFR2, CD31 [vascular endothelial cells (ECs)] and podoplanin (lymphatic ECs). The greatest change was observed in podoplanin expression, corresponding to a 60% reduction in lymphatic vessel density. Conclusions: FDG-PET responses in cycle 1 did not predict for regorafenib clinical benefit in mCRC patients. Targeting lymphatic/vascular ECs in the tumor microenvironment may be a more significant antitumor mechanism of regorafenib than MAP kinase pathway inhibition. Clinical trial information: NCT01189903.