Wang, Kenneth

Despite substantial drug development efforts, pancreatic adenocarcinoma (PDAC) remains a difficult disease to treat, and surgical resection is the only potentially curative option. Unfortunately, 80% of patients are ineligible for surgery due to the presence of invasive disease and/or distant metastases at the time of diagnosis. Treatment strategies geared towards reclassifying these patients as surgical candidates by reducing metastatic burden represents the most promising approach to improve long-term survival. We describe a photodynamic therapy (PDT) based approach that, in combination with the first-line chemotherapeutic nab-paclitaxel, effectively addresses distant metastases in three separate orthotopic PDAC models in immunodeficient mice. In addition to effectively controlling local tumor growth, PDT plus nab-paclitaxel primes the tumor to elicit systemic effects and reduce or abrogate metastases. This combination dramatically inhibits (up to 100%) the eventual development of metastases in models of early stage PDAC, and completely eliminates metastasis in 55% of animals with already established distant disease in late-stage models. Our findings suggest that this light activation process initiates local biological and/or physiological changes within the tumor microenvironment that can be leveraged to treat both localized and distant disease, and potentially reclassify patients with previously inoperable disease as surgical candidates.

AbstractBackground and AimRecently, the BLI Adenoma Serrated International Classification (BASIC) system was developed by European experts to differentiate colorectal polyps. Our aim was to validate the BASIC classification system among the US‐based endoscopy experts.MethodsParticipants utilized a web‐based interactive learning system where the group was asked to characterize polyps using the BASIC criteria: polyp surface (presence of mucus, regular/irregular and [pseudo]depressed), pit appearance (featureless, round/non‐round with/without dark spots; homogeneous/heterogeneous distribution with/without focal loss), and vessels (present/absent, lacy, peri‐cryptal, irregular). The final testing consisted of reviewing BLI images/videos to determine whether the criteria accurately predicted the histology results. Confidence in adenoma identification (rated “1” to “5”) and agreement in polyp (adenoma vs non‐adenoma) identification and characterization per BASIC criteria were derived. Strength of interobserver agreement with kappa (k) value was reported for adenoma identification.ResultsTen endoscopy experts from the United States identified conventional adenoma (vs non‐adenoma) with 94.4% accuracy, 95.0% sensitivity, 93.8% specificity, 93.8% positive predictive value, and 94.9% negative predictive value using BASIC criteria. Overall strength of interobserver agreement was high: kappa 0.89 (0.82–0.96). Agreement for the individual criteria was as follows: surface mucus (93.8%), regularity (65.6%), type of pit (40.6%), pit visibility (66.9%), pit distribution (57%), vessel visibility (73%), and being lacy (46%) and peri‐cryptal (61%). The confidence in diagnosis was rated at high ≥4 in 67% of the cases.ConclusionsA group of US‐based endoscopy experts have validated a simple and easily reproducible BLI classification system to characterize colorectal polyps with >90% accuracy and a high level of interobserver agreement.

Receptor heterogeneity in cancer is a major limitation of molecular targeting for cancer therapeutics. Single-receptor-targeted treatment exerts selection pressures that result in treatment escape for low-receptor-expressing tumor subpopulations. To overcome this potential for heterogeneity-driven resistance to molecular targeted photodynamic therapy (PDT), we present for the first time a triple-receptor-targeted photoimmuno-nanoconjugate (TR-PIN) platform. TR-PIN functionalization with cetuximab, holo-transferrin, and trastuzumab conferred specificity for epidermal growth factor receptor (EGFR), transferrin receptor (TfR), and human epidermal growth factor receptor 2 (HER-2), respectively. The TR-PINs exhibited up to a 24-fold improvement in cancer cell binding compared with EGFR-specific cetuximab-targeted PINs (Cet-PINs) in low-EGFR-expressing cell lines. Photodestruction using TR-PINs was significantly higher than the monotargeted Cet-PINs in heterocellular 3D in vitro models of heterogeneous pancreatic ductal adenocarcinoma (PDAC; MIA PaCa-2 cells) and heterogeneous head and neck squamous cell carcinoma (HNSCC, SCC9 cells) containing low-EGFR-expressing T47D (high TfR) or SKOV-3 (high HER-2) cells. Through their capacity for multiple tumor target recognition, TR-PINs can serve as a unique and amenable platform for the effective photodynamic eradication of diverse tumor subpopulations in heterogeneous cancers to mitigate escape for more complete and durable treatment responses.

Abstract Introduction: Multiple myeloma (MM) is a hematologic cancer that mostly affects elderly patients who are at increased risk for development of cardiac-related comorbidities due to age-, disease-, and treatment-related factors. In real world data, approximately 25-30% of MM patients are hospitalized for a cardiac event after MM diagnosis (Kistler et al. American Society Hematology 2012 Annual Meeting, poster 2916). The proteasome inhibitor, carfilzomib, is approved for treatment of patients with relapsed or refractory MM. In carfilzomib clinical trials, grade 3 or higher cardiac failure was reported for ~4% of patients (Stewart et al. NEJM 2015;372:142-52, Dimopoulos et al. Lancet Oncol 2016;17:27-38). In this retrospective analysis, we sought to evaluate the incidence rate (IR) of cardiac events in MM patients treated with carfilzomib in a real-world setting in the US and to describe differences in baseline characteristics between carfilzomib-treated MM patients who do and do not have cardiac events. Methods: Newly-diagnosed MM patients with symptomatic disease were identified in the Truven MarketScan claims database from 1/1/05 to 6/30/15 using an algorithm validated for ascertainment of MM patients in claims data (Princic et al. Blood 2015;126:4521). All carfilzomib-treated patients were included in the analysis. The first dose of carfilzomib was the index date. The baseline period was 12 months prior to the MM diagnosis date to the index date. Cardiac events (hypertension, heart failure, ischemic heart disease, arrhythmias and conduction disorders, and cardiomyopathy) were identified during baseline by inpatient (IP) or outpatient (OP) claims and after index date by primary diagnosis on IP claims (hospitalized events). Logistic regression was used to estimate baseline covariates associated with any cardiac event. Due to sample size constraints, multivariate regression was not performed. The incidence rate (IR) per 1000 patient-years (PYRs) and associated 95% confidence interval (CI) of hospitalized cardiac events during carfilzomib treatment which included 30 days after the last carfilzomib dose were calculated among patients without a history of the corresponding hospitalized event during the baseline period. Results: The cohort included 498 MM patients treated with carfilzomib; 108 (22%) patients had ≥1 cardiac event identified by both IP and OP claims and 24 (5%) had ≥1 hospitalized cardiac event. Of the 24 hospitalized patients, 14 were hospitalized during carfilzomib treatment (median days to onset = 104) and 8 were hospitalized after carfilzomib treatment (>30 days post dosing; median days to onset = 284). The median age (range) of the 24 patients with hospitalized cardiac events and those with no hospitalized cardiac claims (n=474) was 62 (37, 79) and 61 (36, 96) years, respectively (Table). Baseline medical history of any cardiac event was evident for 92% of hospitalized patients and 84% of non-hospitalized patients. Among hospitalized patients, 25% were over 75 years as compared with 13% of non-hospitalized patients. In univariate analysis, patients with baseline amyloidosis, hypertensive chronic kidney disease, and chronic kidney disease had higher odds of having a hospitalized cardiac event. No significant differences were seen in the proportion of patients with or without a hospitalized cardiac event when evaluated by line of therapy or by carfilzomib treatment regimen (monotherapy or combination). Among patients aged 75+ years, 8.7% were hospitalized, while 2.5% and 4.9% of 65-74 and 18-64 year old patients were hospitalized, respectively (Table). IR per 1000 PYRs [95% CI] among the 14 carfilzomib-treated MM patients hospitalized for any cardiac event during the carfilzomib treatment period was 89.7 (49.0; 150.5) - see Figure for IRs of specific cardiac events. Conclusions: Among carfilzomib-treated patients in a US claims database, hospitalization for a cardiac event was uncommon (~5%) and does not exceed what has been observed in MM patients. Patients at highest risk for cardiac hospitalizations had a history of amyloidosis or chronic renal failure. Additional analyses in much larger populations are needed to better understand risk factors for these events. Disclosures Chari: Array Biopharma: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Amgen Inc.: Honoraria, Research Funding; Novartis: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Pharmacyclics: Research Funding; Janssen: Consultancy, Research Funding. Aggarwal:Amgen: Employment, Equity Ownership. Mezzi:Amgen Inc.: Employment, Equity Ownership. Wang:Amgen Inc.: Employment, Equity Ownership. Kim:Amgen Inc.: Employment, Equity Ownership. Zhu:Amgen Inc.: Consultancy. Braunlin:Amgen Inc.: Employment, Equity Ownership. Werther:Amgen Inc.: Employment, Equity Ownership. Mikhael:Abbvie: Research Funding; Celgene: Research Funding; Sanofi: Research Funding; Onyx: Research Funding.

Bevacizumab‐pemetrexed/cisplatin ( BEV ‐ PEM / CIS ) is a first‐line therapeutic for advanced nonsquamous non‐small cell lung cancer. Bevacizumab potentiates PEM / CIS cytotoxicity by inducing transient tumor vasculature normalization. BEV ‐ PEM / CIS has a narrow therapeutic window. Therefore, it is an attractive target for administration schedule optimization. The present study leverages our previous work on BEV ‐ PEM / CIS pharmacodynamic modeling in non‐small cell lung cancer–bearing mice to estimate the optimal gap in the scheduling of sequential BEV ‐ PEM / CIS . We predicted the optimal gap in BEV ‐ PEM / CIS dosing to be 2.0 days in mice and 1.2 days in humans. Our simulations suggest that the efficacy loss in scheduling BEV ‐ PEM / CIS at too great of a gap is much less than the efficacy loss in scheduling BEV ‐ PEM / CIS at too short of a gap.

Abstract Background Post-surgical complications such as leaks are the source of considerable morbidity and mortality. Success of conservative interventions is highly variable. Recurrence after surgical repair is also not uncommon. Our aim was to develop novel endoscopic strategies to maximize negative intracavitary pressure to manage leaks in cases where conventional management either failed or were not feasible. Methods We have used transluminal locking loop drains with low intermittent suction in the management of non-healing leaks in various areas. An example presented here illustrates this concept where a 68-year-old male patient underwent paraesophageal hernia repair with Nissen fundoplication. Patient presented 3 weeks later with fistula leading to a 13 cm meditational abscess. Patient developed right hemiparesis requiring tissue plasminogen activator (tPA). Post-tPA patient developed hemoptysis and hematemesis requiring emergency intubation. The defect in the esophagus was 6–8 mm. Endoscopic repair with stitching or clipping would have left a large undrained cavity with a potential to expand. Endoscopic repair with transcutaneous drain placement was challenging due to recent tPA and a difficult location. Moreover there was potential to develop esophago- pleural- broncho- cutaneous fistula. Endoscopic vacuum therapy was felt to be a suboptimal choice. Patient was high-risk surgical candidate as it would have required radical surgery in the setting of tPA.Upper endoscopy was performed and the cavity was debrided. No direct communication with bronchopulmonary tree noted. A transnasal guidewire assisted 16 Fr, 60 cm locking loop drain was placed and connected to low intermittent suction that was switched to bulb based suction. Results The output from naso-cavity drain decreased nearly 100 cc per day in the first 5 days and the size reduced by 30, 50 and 80% by day 5, 9 and 12 respectively. Near complete elimination of the cavity was observed on day 15. Esophagogram showed complete resolution of the leak and computerized tomography revealed no residual cavity Conclusion Developing transluminal endoscopic strategies to maximize negative intracavitary pressure helps expedite the healing of resistant postsurgical leaks. This technique avoids the need for frequent drain changes that remains a challenge for vacuum therapy. Disclosure All authors have declared no conflicts of interest.

Abstract Background The neo-squamous epithelium that replaces columnar epithelium after successful endoscopic ablation of Barrett's esophagus (BE) has not been fully characterized in regard to its structural and functional integrity. Intercellular space is a surrogate marker for epithelial structural integrity and mucosal impedance (MI) is a surrogate for transepithelial resistance and thus epithelial functional integrity. Impairment of the structural and functional integrity may influence recurrence following successful ablation. We aimed to measure the esophageal epithelial intercellular space diameter and MI in the neo-squamous and normal squamous epithelium of patients who underwent successful radiofrequency ablation for dysplastic BE. Methods Forty patients with complete remission of intestinal metaplasia (CRIM) (defined as two negative surveillance endoscopies for intestinal metaplasia) were prospectively recruited. Patients were excluded if they had endoscopic evidence of esophagitis. MI measurements were taken at 1 cm above the GE junction and 2 cm above the prior BE segment (targeting uninvolved squamous epithelium), using a novel through the scope MI probe. Endoscopic biopsies were also taken at these corresponding sites to assess intercellular space diameter using transmission electron microscopy (TEM) using standard techniques. Results 80% of patients were male with a mean age of 69 years. Mean follow since achieving CRIM was 30 months. 39 patients underwent RFA for dysplasia. The mean intercellular space diameter was higher in the neo-squamous epithelium (1.01 μm) when compared to the untreated native squamous epithelium (0.96 μm) [Difference of 0.056 μm, 95% CI of -0.036 to 0.148, P = 0.228]. The mean MI was significantly lower in the neosquamous epithelium (4001.3 Ω) when compared to the untreated native epithelium (5168.1 Ω) [Difference of 1166.7 Ω, 95% CI 418.8 to 1914.6, P = 0.003]. Conclusion Neo-squamous epithelium that replaces BE epithelium following successful endoscopic therapy for BE appears to be functionally and likely structurally deficient with regards to acid reflux barrier function, when compared to native squamous esophageal epithelium. This impairment may be associated with recurrence following successful ablation. Disclosure All authors have declared no conflicts of interest.

Abstract Background Endoscopic mucosal resection (EMR) can be performed en-bloc in Barrett's esophagus (BE) lesions that are ≤2 cm in size. The true size of a BE lesion may be underestimated under white light endoscopy, limiting the rate of en-bloc resection. Volumetric laser endomicroscopy (VLE) provides high-resolution cross-sectional imaging of BE. A greater number of VLE glands are associated with BE dysplasia and may help predict lesion size. The aim of this study was to determine the association between VLE gland count and outcome of resection. Methods EMR specimens from patients with a history of dysplastic BE were imaged with VLE. EMRs performed on BE lesions ≤2cm in size with intent at en-bloc resection were included. Manual quantification of epithelial glands was performed in blinded fashion. Image visualization enhancement software was used to quantify the surface area occupied by epithelial glands on en-face VLE. Histologic en-bloc (R0) and incomplete (R1) resection of the targeted lesion was defined by the absence and presence of dysplasia and/or cancer at the specimen margins respectively. Results The study sample consisted of 37 EMRs from 31 patients. The mean (SD) size of EMRs was 1.04 (0.37) cm. Pathology showed low-grade dysplasia (N = 12), high-grade dysplasia (N = 19), and intramucosal cancer (N = 6). The en-bloc resection rate was 37.8% (R0: N = 14; R1: N = 23). The mean (SD) number of epithelial glands was 13.0 (6.7) and 28.8 (23.9) for R0 and R1 specimens, respectively, with a statistically significant mean difference of 15.8 glands (95% CI: 2–29, P = 0.02) between the two groups. A gland count of 28 or higher per EMR specimen predicted R1 with 100% sensitivity and 39% specificity (ROC: 0.69). The mean (SD) surface area occupied by epithelial glands in R0 and R1 specimens was 0.98 (1.1) mm2 and 2.3 (2.4) mm2, respectively. There was strong correlation between manual gland counts and epithelial gland surface area (R2: 0.81, P < 0.001). Conclusion A higher number of VLE glands in EMR specimens is associated with a lower en-bloc resection rate suggesting that white-light endoscopy underestimates lesion size and that VLE may have a potential role in lesion margin assessment. Disclosure All authors have declared no conflicts of interest.