Quantifying Patient Risk Threshold in Managing Pancreatic Intraductal Papillary Mucinous Neoplasms.

OBJECTIVE: We aimed to better understand patients' treatment preferences and quantify the level of cancer risk at which treatment preferences change (risk threshold) to inform better counseling of patients with intraductal papillary mucinous neoplasms (IPMNs). SUMMARY BACKGROUND DATA: The complexity of IPMN management provides an opportunity to align treatment with individual preference. METHODS: We surveyed a sample of healthy volunteers simulating a common scenario: undergoing an imaging study that incidentally identifies an IPMN. In the scenario, the estimated risk of cancer in the IPMN was 5%. Patients were asked their treatment preference (surgery or surveillance), to quantify the level of cancer risk in the IPMN at which their treatment preference would change (i.e. risk threshold), and their level of cancer anxiety as measured on a 5-point Likert scale. We examined associations between participant characteristics, treatment preferences, and risk threshold using multivariable linear regression. RESULTS: The median risk threshold among the 520 participants was 25% (IQR 2.3-50%). The risk threshold had a bimodal distribution: 40% of participants had a risk threshold between 0-10% and 47% had a risk threshold above 30%. When informed that the risk of cancer was 5%, 62% of participants (n=323) preferred surveillance, and the remaining 38% (n=197) preferred surgery. After adjusting for potential confounders, participants who expressed "worry" or "extreme worry" about the malignancy risk of IPMN had significantly lower risk thresholds than participants who were "not at all worried" (Coefficient -12, 95%CI -21 to -2, P=0.015 and Coefficient -18, 95%CI -29 to -8, P<0.001, respectively). CONCLUSIONS: Participants varied in treatment preference and risk threshold of incidentally identified IPMNs. Given the uncertainty in estimating the true malignant potential of IPMNs, a better understanding of a patient's risk threshold, as influenced by patient concern about malignancy, will help inform the shared decision-making process.

Defining the Minimal and Optimal Thresholds for Lymph Node Resection and Examination for Intraductal Papillary Mucinous Neoplasm Derived Pancreatic Cancer: A Multicenter Retrospective Analysis.

OBJECTIVE: To establish minimal and optimal lymphadenectomy thresholds for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and evaluate their prognostic value. BACKGROUND: Current guidelines recommend a minimum of 12-15 lymph nodes (LNs) in PDAC. This is largely based on pancreatic intraepithelial neoplasia (PanIN)-derived PDAC, a biologically distinct entity from IPMN-derived PDAC. METHODS: Multicenter retrospective study including consecutive patients undergoing upfront surgery for IPMN-derived PDAC was conducted. The minimum cut-off for lymphadenectomy was defined as the maximum number of LNs where a significant node positivity difference was observed. Maximally selected log-rank statistic was used to derive the optimal lymphadenectomy cut-off (maximize survival). Kaplan-Meier curves and log-rank tests were used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariable Cox-regression was used to determine hazard ratios (HR) with 95% confidence intervals (95%CI). RESULTS: In 341 patients with resected IPMN-derived PDAC, the minimum number of LNs needed to ensure accurate nodal staging was 10 (P=0.040), whereas ≥20 LNs was the optimal number associated with improved OS (80.3 vs. 37.2 mo, P<0.001). Optimal lymphadenectomy was associated with improved OS [HR:0.57 (95%CI 0.39-0.83)] and RFS [HR:0.70 (95%CI 0.51-0.97)] on multivariable Cox-regression. On sub-analysis the optimal lymphadenectomy cut-offs for pancreatoduodenectomy, distal pancreatectomy, and total pancreatectomy were 20 (P<0.001), 23 (P=0.160), and 25 (P=0.008). CONCLUSION: In IPMN-derived PDAC, lymphadenectomy with at least 10 lymph nodes mitigates under-staging, and at least 20 lymph nodes is associated with the improved survival. Specifically, for pancreatoduodenectomy and total pancreatectomy, 20 and 25 lymph nodes were the optimal cut-offs.

Lung-Mimetic Hydrofoam Sealant to Treat Pulmonary Air Leak.

Pulmonary air leak is the most common complication of lung surgery, contributing to post-operative morbidity in up to 60% of patients; yet, there is no reliable treatment. Available surgical sealants do not match the demanding deformation mechanics of lung tissue; and therefore, fail to seal air leak. To address this therapeutic gap, a sealant with structural and mechanical similarity to subpleural lung is designed, developed, and systematically evaluated. This "lung-mimetic" sealant is a hydrofoam material that has alveolar-like porous ultrastructure, lung-like viscoelastic properties (adhesive, compressive, tensile), and lung extracellular matrix-derived signals (matrikines) to support tissue repair. In biocompatibility testing, the lung-mimetic sealant shows minimal cytotoxicity and immunogenicity in vitro. Human primary monocytes exposed to sealant matrikines in vitro upregulate key genes (MARCO, PDGFB, VEGF) known to correlate with pleural wound healing and tissue repair in vivo. In rat and swine models of pulmonary air leak, this lung-mimetic sealant rapidly seals air leak and restores baseline lung mechanics. Altogether, these data indicate that the lung-mimetic sealant can effectively seal pulmonary air leak and promote a favorable cellular response in vitro.

Recovery of extracorporeal lungs using cross-circulation with injured recipient swine.

OBJECTIVE: Lung transplantation remains limited by the shortage of healthy organs. Cross-circulation with a healthy swine recipient provides a durable physiologic environment to recover injured donor lungs. In a clinical application, a recipient awaiting lung transplantation could be placed on cross-circulation to recover damaged donor lungs, enabling eventual transplantation. Our objective was to assess the ability of recipient swine with respiratory compromise to tolerate cross-circulation and support recovery of donor lungs subjected to extended cold ischemia. METHODS: Swine donor lungs (n = 6) were stored at 4 °C for 24 hours while recipient swine (n = 6) underwent gastric aspiration injury before cross-circulation. Longitudinal multiscale analyses (blood gas, bronchoscopy, radiography, histopathology, cytokine quantification) were performed to evaluate recipient swine and extracorporeal lungs on cross-circulation. RESULTS: Recipient swine lung injury resulted in sustained, impaired oxygenation (arterial oxygen tension/inspired oxygen fraction ratio 205 ± 39 mm Hg vs 454 ± 111 mm Hg at baseline). Radiographic, bronchoscopic, and histologic assessments demonstrated bilateral infiltrates, airway cytokine elevation, and significantly worsened lung injury scores. Recipient swine provided sufficient metabolic support for extracorporeal lungs to demonstrate robust functional improvement (0 hours, arterial oxygen tension/inspired oxygen fraction ratio 138 ± 28.2 mm Hg; 24 hours, 539 ± 156 mm Hg). Multiscale analyses demonstrated improved gross appearance, aeration, and cellular regeneration in extracorporeal lungs by 24 hours. CONCLUSIONS: We demonstrate that acutely injured recipient swine tolerate cross-circulation and enable recovery of donor lungs subjected to extended cold storage. This proof-of-concept study supports feasibility of cross-circulation for recipients with isolated lung disease who are candidates for this clinical application.

Outcomes after primary tumor resection of metastatic pancreatic neuroendocrine tumors: An analysis of the National Cancer Database.

INTRODUCTION: There is no consensus regarding the role of primary tumor resection for patients with metastatic pancreatic neuroendocrine tumors (panNET). We assessed surgical treatment patterns and evaluated the survival impact of primary tumor resection in patients with metastatic panNET. METHODS: Patients with synchronous metastatic nonfunctional panNET in the National Cancer Database (2004-2016) were categorized based on whether they underwent primary tumor resection. We used logistic regressions to assess associations with primary tumor resection. We performed survival analyses with Kaplan-Meier survival functions, log-rank test, and Cox proportional hazard regression within a propensity score matched cohort. RESULTS: In the overall cohort of 2613 patients, 68% (n = 839) underwent primary tumor resection. The proportion of patients who underwent primary tumor resection decreased over time from 36% (2004) to 16% (2016, p < 0.001). After propensity score matching on age at diagnosis, median income quartile, tumor grade, size, liver metastasis, and hospital type, primary tumor resection was associated with longer median overall survival (OS) (65 vs. 24 months; p < 0.001) and was associated with lower hazard of mortality (HR: 0.39, p < 0.001). CONCLUSION: Primary tumor resection was significantly associated with improved OS, suggesting that, if feasible, surgical resection can be considered for well-selected patients with panNET and synchronous metastasis.

Sound-guided assessment and localization of pulmonary air leak.

Pulmonary air leak is the most common complication of lung surgery, with air leaks that persist longer than 5 days representing a major source of post-surgery morbidity. Clinical management of air leaks is challenging due to limited methods to precisely locate and assess leaks. Here, we present a sound-guided methodology that enables rapid quantitative assessment and precise localization of air leaks by analyzing the distinct sounds generated as the air escapes through defective lung tissue. Air leaks often present after lung surgery due to loss of tissue integrity at or near a staple line. Accordingly, we investigated air leak sounds from a focal pleural defect in a rat model and from a staple line failure in a clinically relevant swine model to demonstrate the high sensitivity and translational potential of this approach. In rat and swine models of free-flowing air leak under positive pressure ventilation with intrapleural microphone 1 cm from the lung surface, we identified that: (a) pulmonary air leaks generate sounds that contain distinct harmonic series, (b) acoustic characteristics of air leak sounds can be used to classify leak severity, and (c) precise location of the air leak can be determined with high resolution (within 1 cm) by mapping the sound loudness level across the lung surface. Our findings suggest that sound-guided assessment and localization of pulmonary air leaks could serve as a diagnostic tool to inform air leak detection and treatment strategies during video-assisted thoracoscopic surgery (VATS) or thoracotomy procedures.

Time to Curative-Intent Surgery in Gastric Cancer Shows a Bimodal Relationship with Overall Survival.

BACKGROUND: Time to treatment (TTT) varies widely for patients with gastric cancer. We aimed to evaluate relationships between time to treatment, overall survival (OS), and other surgical outcomes in patients with stage I-III gastric cancer. METHODS: We identified patients with clinical stage I-III gastric cancer who underwent curative-intent gastrectomy within the National Cancer Database (2006-2015) and grouped them by treatment sequence: neoadjuvant chemotherapy or surgery upfront. We defined TTT as weeks from diagnosis to treatment initiation (neoadjuvant chemotherapy or definitive surgical procedure, respectively). Survival differences were assessed by Kaplan-Meier estimate, Cox proportional hazard regression, and log rank test. RESULTS: Among the 22,846 patients with stage I-III gastric cancer, most (56%) received surgery upfront. Median TTT was 5 weeks (IQR 4-7) and 6 weeks (IQR 3-9) for patients in the neoadjuvant and surgery upfront groups, respectively. In the neoadjuvant group, increasing TTT was significantly associated with increasing median OS up to TTT of 5 weeks, with no change in median OS when TTT was > 5 weeks. In the surgery group, increasing TTT was significantly associated with increasing median OS up to 6 weeks; however, increasing TTT between 14 and 21 weeks was associated with decreasing median OS. CONCLUSIONS: The relationship between time to treatment and survival outcomes is non-linear. Among patients who underwent surgery upfront, the relationship between time to treatment and OS was bimodal, suggesting that deferring definitive surgery, up to 14 weeks, is not associated with worse OS or oncologic outcomes. The relationship between time to treatment and overall survival among patients was bimodal, suggesting that deferring definitive surgery up to 14 weeks is not associated with worse OS.

Natural History of Stage IV Pancreatic Cancer. Identifying Survival Benchmarks for Curative-intent Resection in Patients With Synchronous Liver-only Metastases.

OBJECTIVE: To evaluate long-term oncologic outcomes of patients with stage IV pancreatic ductal adenocarcinoma and to identify survival benchmarks for comparison when considering resection in these patients. BACKGROUND: Highly selected cohorts of patients with liver-oligometastatic pancreas cancer have reported prolonged survival after resection. The long-term impact of surgery in this setting remains undefined because of a lack of appropriate control groups. METHODS: We identified patients with clinical stage IV pancreatic ductal adenocarcinoma with synchronous liver metastases within our cancer registry. We estimated overall survival (OS) among various patient subgroups using the Kaplan-Meier method. To mitigate immortal time bias, we analyzed long-term outcomes of patients who survived beyond 12 months (landmark time) from diagnosis. RESULTS: We identified 241 patients. Median OS was 7 months (95% CI, 5-9), both overall and for patients with liver-only metastasis (n=144). Ninety patients (38% of liver only; 40% of whole cohort) survived at least 12 months; those who received chemotherapy in this subgroup had a median OS of 26 months (95% CI, 17-39). Of these patients, those with resectable or borderline resectable primary tumors and resectable liver-only metastasis (n=9, 4%) had a median OS of 39 months (95% CI, 13-NR). CONCLUSIONS: The 4% of our cohort that were potentially eligible for surgery experienced a prolonged survival compared with all-comers with stage IV disease. Oncologic outcomes of patients undergoing resection of metastatic pancreas cancer should be assessed in the context of the expected survival of patients potentially eligible for surgery and not relative to all patients with stage IV disease.

Regional Patterns of Hospital-Level Guideline Adherence in Gastric Cancer: An Analysis of the National Cancer Database.

BACKGROUND: Adherence to evidence-based guidelines for gastric cancer is low, particularly at the hospital level, despite a strong association with improved overall survival (OS). We aimed to evaluate patterns of hospital and regional adherence to National Comprehensive Cancer Network guidelines for gastric cancer. METHODS: Using the National Cancer Database (2004-2015), we identified patients with stage I-III gastric cancer. Hospital-level guideline adherence was calculated by dividing the patients who received guideline adherent care by the total patients treated at that hospital. OS was estimated for each hospital. Associations between adherence, region, and survival were compared using mixed-effects, hierarchical regression. RESULTS: Among 576 hospitals, the median hospital guideline adherence rate was 25% (range 0-76%) and varied significantly by region (p = 0.001). Adherence was highest in the Middle Atlantic (29%) and lowest in the East South Central region (19%); hospitals in the New England, Middle Atlantic, and East North Central regions were more likely to be guideline adherent than those in the East South Central region (all p < 0.05), after adjusting for patient and hospital mix. Most (35%) of the adherence variation was attributable to the hospital. Median 2-year OS varied significantly by region. After adjusting for hospital and patient mix, hazard of mortality was 17% lower in the Middle Atlantic (hazard ratio 0.82, 95% confidence interval 0.74-0.90) relative to the East South Central region, with most of the variation (54%) attributable to patient-level factors. CONCLUSIONS: Hospital-level guideline adherence for gastric cancer demonstrated significant regional variation and was associated with longer OS, suggesting that efforts to improve guideline adherence should be directed toward lower-performing hospitals.

A clinically relevant model of acute respiratory distress syndrome in human-size swine.

Despite over 30 years of intensive research for targeted therapies, treatment of acute respiratory distress syndrome (ARDS) remains supportive in nature. With mortality upwards of 30%, a high-fidelity pre-clinical model of ARDS, on which to test novel therapeutics, is urgently needed. We used the Yorkshire breed of swine to induce a reproducible model of ARDS in human-sized swine to allow the study of new therapeutics, from both mechanistic and clinical standpoints. For this, animals were anesthetized, intubated and mechanically ventilated, and pH-standardized gastric contents were delivered bronchoscopically, followed by intravenous infusion of Escherichia coli-derived lipopolysaccharide. Once the ratio of arterial oxygen partial pressure (PaO2) to fractional inspired oxygen (FIO2) had decreased to <150, the animals received standard ARDS treatment for up to 48 h. All swine developed moderate to severe ARDS. Chest radiographs taken at regular intervals showed significantly worse lung edema after induction of ARDS. Quantitative scoring of lung injury demonstrated time-dependent increases in interstitial and alveolar edema, neutrophil infiltration, and mild to moderate alveolar membrane thickening. This pre-clinical model of ARDS in human-sized swine recapitulates the clinical, radiographic and histopathologic manifestations of ARDS, providing a tool to study therapies for this highly morbid lung disease.

Outcomes After Surgical Palliation of Patients With Gastric Cancer.

INTRODUCTION: Surgery is an option for symptom palliation in patients with metastatic gastric cancer. Operative outcomes after palliative interventions are largely unknown. Herein, we assess the trends of surgical palliation use for patients with gastric cancer and describe outcomes of patients undergoing surgical palliation compared to nonsurgical palliation. METHODS: Patients with clinical Stage IV gastric cancer in the National Cancer Database (2004-2015) who received surgical or nonsurgical palliation were selected. We identified factors associated with palliative surgery. Survival differences were assessed by Kaplan-Meier estimate, Cox proportional hazard regression, and log rank test. RESULTS: Six thousand eight hundred twenty nine patients received palliative care for gastric cancer. Most patients (87%, n = 5944) received nonsurgical palliation: 29% radiation therapy, 57% systemic treatment, and 14% pain management. The number of patients receiving palliative care increased between 2004 and 2015; however, use of surgical palliation declined significantly (22% in 2004, 8% in 2015; P < 0.001). Median overall survival (OS) for the cohort was 5.65 mo (95% confidence interval 5.45-5.85); 1-year and 2-year OS were 24% and 9%, respectively. Older age at diagnosis and diagnosis between 2004 and 2006 were significantly associated with undergoing surgical palliation. Patients who underwent surgical palliation had significantly shorter median OS and a 20% higher hazard of mortality than those who received nonsurgical palliation. CONCLUSIONS: Patients with metastatic gastric cancer experience very short survival. While palliative surgery is used infrequently, the observed association with shorter median OS underscores the importance of careful patient selection. Palliative surgery should be offered judiciously and expectations about outcomes clearly established.

Pathological remodeling of distal lung matrix in end-stage cystic fibrosis patients.

BACKGROUND: Manifestations of cystic fibrosis, although well-characterized in the proximal airways, are understudied in the distal lung. Characterization of the cystic fibrosis lung 'matrisome' (matrix proteome) has not been previously described, and could help identify biomarkers and inform therapeutic strategies. METHODS: We performed liquid chromatography-mass spectrometry, gene ontology analysis, and multi-modal imaging, including histology, immunofluorescence, and electron microscopy for a comprehensive evaluation of distal human lung extracellular matrix (matrix) structure and composition in end-stage cystic fibrosis. RESULTS: Quantitative proteomic profiling identified sixty-eight (68) matrix constituents with significantly altered expression in end-stage cystic fibrosis. Over 90% of significantly different matrix peptides detected, including structural and basement membrane proteins, were expressed at lower levels in cystic fibrosis. However, the total abundance of matrix in cystic fibrosis lungs was not significantly different from control lungs, suggesting that cystic fibrosis leads to loss of diversity among lung matrix proteins rather than an absolute loss of matrix. Visualization of distal lung matrix via immunofluorescence and electron microscopy revealed pathological remodeling of distal lung tissue architecture and loss of alveolar basement membrane, consistent with significantly altered pathways identified by gene ontology analysis. CONCLUSIONS: Dysregulation of matrix organization and aberrant wound healing pathways are associated with loss of matrix protein diversity and obliteration of distal lung tissue structure in end-stage cystic fibrosis. While many therapeutics aim to functionally restore defective cystic fibrosis transmembrane conductance regulator (CFTR), drugs that target dysregulated matrix pathways may serve as adjunct interventions to support lung recovery.

Adherence to guidelines at the patient- and hospital-levels is associated with improved overall survival in patients with gastric cancer.

BACKGROUND AND OBJECTIVES: Adherence to evidence-based guidelines in gastric cancer is low. We aimed to evaluate adherence to National Comprehensive Cancer Network (NCCN) Guidelines for gastric cancer at both patient- and hospital-levels and examine associations between guideline adherence and treatment outcomes, including overall survival (OS). METHODS: We applied stage-specific, annual NCCN Guidelines (2004-2015) to patients with gastric cancer treated with curative-intent within the National Cancer Database and compared characteristics of patients who did and did not receive guideline-adherent care. Hospitals were evaluated by guideline adherence rate. We identified associations with OS through multivariable Cox regression. RESULTS: Of 37 659 patients included, 32% received NCCN Guideline-adherent treatment. OS was significantly associated with both guideline adherence (51 months for patients receiving guideline-adherent treatment vs. 22 for patients receiving nonadherent treatment, p < 0.001). Treatment at a hospital with higher adherence was associated with longer OS (21 months for patients treated at lowest adherence quartile hospitals vs. 37 months at highest adherence quartile hospitals, p < 0.001), regardless of type of treatment received. CONCLUSIONS: Guideline-adherent treatment was strongly associated with longer median OS. Guideline adherence should be used as a benchmark for focused quality improvement for physicians taking care of patients with gastric cancer and institutions at large.

Systemic therapy for duodenal adenocarcinoma: An analysis of the National Cancer Database (NCDB).

BACKGROUND: National Comprehensive Cancer Network guidelines recommend resection and adjuvant chemotherapy for patients with locally advanced duodenal adenocarcinoma. Outcomes after systemic treatment in this rare malignancy have not been well studied. We examined utilization patterns of systemic treatment and compared overall survival of patients receiving neoadjuvant therapy, surgery alone, and adjuvant therapy. METHODS: Patients with stage 0 to III duodenal adenocarcinoma undergoing curative-intent surgery were identified within the National Cancer Database from 2006 to 2015. Outcomes, including median overall survival and 30- and 90-day mortality, were compared based on treatment sequence (neoadjuvant, adjuvant, or surgery alone). Propensity score matching on likelihood of receiving systemic treatment and landmark analysis were performed to mitigate bias. RESULTS: Of the 2,956 patients meeting inclusion criteria, most patients with known clinical stage had locally advanced disease (72%), of which 53% received systemic therapy (8% neoadjuvant, 45% adjuvant). After landmark analysis on the propensity matched cohort, patients with locally advanced disease who received systemic treatment had longer median overall survival compared to patients who underwent surgery alone (49 vs 40 months, P = .018) and a 20% lower hazard of mortality (hazard ratio 0.80, 95% confidence interval 0.69-0.93, P = .003). Patients who received neoadjuvant and adjuvant therapy had similar survival outcomes. CONCLUSION: Adjuvant therapy was underutilized in patients with National Comprehensive Cancer Network guideline indications, despite an association with longer median overall survival and decreased hazard of mortality. Neoadjuvant therapy, although rarely used, had similar survival to adjuvant therapy. Given its other potential benefits, systemic treatment in the neoadjuvant setting may be a reasonable option in adequately selected patients with clinically advanced duodenal adenocarcinoma.

Surgical Treatment of Patients with Poorly Differentiated Pancreatic Neuroendocrine Carcinoma: An NCDB Analysis.

BACKGROUND: Consensus guidelines discourage resection of poorly differentiated pancreatic neuroendocrine carcinoma (panNEC) given its association with poor long-term survival. This study assessed treatment patterns and outcomes for this rare malignancy using the National Cancer Database (NCDB). METHODS: Patients with non-functional pancreatic neuroendocrine tumors in the NCDB (2004-2016) were categorized based on pathologic differentiation. Logistic and Cox proportional hazard regressions identified associations with resection and overall survival (OS). Survival was compared using Kaplan-Meier and log-rank tests. RESULTS: Most patients (83%) in the cohort of 8560 patients had well-differentiated tumors (panNET). The median OS was 47 months (panNET, 63 months vs panNEC, 17 months; p < 0.001). Surgery was less likely for older patients (odds ratio [OR], 0.97), patients with panNEC (OR, 0.27), and patients with metastasis at diagnosis (OR, 0.08) (all p < 0.001). After propensity score-matching of these factors, surgical resection was associated with longer OS (82 vs 29 months; p < 0.001) and a decreased hazard of mortality (hazard ratio [HR], 0.37; p < 0.001). Surgery remained associated with longer OS when stratified by differentiation (98 vs 41 months for patients with panNET and 36 vs 8 months for patients with panNEC). Overall survival did not differ between patients with panNEC who underwent surgery and patients with panNET who did not (both 39 months; p = 0.294). CONCLUSIONS: Poorly differentiated panNEC exhibits poorer survival than well-differentiated panNET. In the current cohort, surgical resection was strongly and independently associated with improved OS, suggesting that patients with panNEC who are suitable operative candidates should be considered for multimodality therapy, including surgery.