An autoinhibitory switch of the LSD1 disordered region controls enhancer silencing.

Transcriptional coregulators and transcription factors (TFs) contain intrinsically disordered regions (IDRs) that are critical for their association and function in gene regulation. More recently, IDRs have been shown to promote multivalent protein-protein interactions between coregulators and TFs to drive their association into condensates. By contrast, here we demonstrate how the IDR of the corepressor LSD1 excludes TF association, acting as a dynamic conformational switch that tunes repression of active cis-regulatory elements. Hydrogen-deuterium exchange shows that the LSD1 IDR interconverts between transient open and closed conformational states, the latter of which inhibits partitioning of the protein's structured domains with TF condensates. This autoinhibitory switch controls leukemic differentiation by modulating repression of active cis-regulatory elements bound by LSD1 and master hematopoietic TFs. Together, these studies unveil alternative mechanisms by which disordered regions and their dynamic crosstalk with structured regions can shape coregulator-TF interactions to control cis-regulatory landscapes and cell fate.

Tissue-Resident Macrophages in Pancreatic Ductal Adenocarcinoma Originate from Embryonic Hematopoiesis and Promote Tumor Progression.

Tumor-associated macrophages (TAMs) are essential components of the cancer microenvironment and play critical roles in the regulation of tumor progression. Optimal therapeutic intervention requires in-depth understanding of the sources that sustain macrophages in malignant tissues. In this study, we investigated the ontogeny of TAMs in murine pancreatic ductal adenocarcinoma (PDAC) models. We identified both inflammatory monocytes and tissue-resident macrophages as sources of TAMs. Unexpectedly, significant portions of pancreas-resident macrophages originated from embryonic development and expanded through in situ proliferation during tumor progression. Whereas monocyte-derived TAMs played more potent roles in antigen presentation, embryonically derived TAMs exhibited a pro-fibrotic transcriptional profile, indicative of their role in producing and remodeling molecules in the extracellular matrix. Collectively, these findings uncover the heterogeneity of TAM origin and functions and could provide therapeutic insight for PDAC treatment.

sc2MeNetDrug: A computational tool to uncover inter-cell signaling targets and identify relevant drugs based on single cell RNA-seq data.

Single-cell RNA sequencing (scRNA-seq) is a powerful technology to investigate the transcriptional programs in stromal, immune, and disease cells, like tumor cells or neurons within the Alzheimer's Disease (AD) brain or tumor microenvironment (ME) or niche. Cell-cell communications within ME play important roles in disease progression and immunotherapy response and are novel and critical therapeutic targets. Though many tools of scRNA-seq analysis have been developed to investigate the heterogeneity and sub-populations of cells, few were designed for uncovering cell-cell communications of ME and predicting the potentially effective drugs to inhibit the communications. Moreover, the data analysis processes of discovering signaling communication networks and effective drugs using scRNA-seq data are complex and involve a set of critical analysis processes and external supportive data resources, which are difficult for researchers who have no strong computational background and training in scRNA-seq data analysis. To address these challenges, in this study, we developed a novel open-source computational tool, sc2MeNetDrug (https://fuhaililab.github.io/sc2MeNetDrug/). It was specifically designed using scRNA-seq data to identify cell types within disease MEs, uncover the dysfunctional signaling pathways within individual cell types and interactions among different cell types, and predict effective drugs that can potentially disrupt cell-cell signaling communications. sc2MeNetDrug provided a user-friendly graphical user interface to encapsulate the data analysis modules, which can facilitate the scRNA-seq data-based discovery of novel inter-cell signaling communications and novel therapeutic regimens.

Neoadjuvant Chemotherapy is Associated with Increased Risk of Postoperative DVT After Distal Pancreatectomy for Pancreatic Adenocarcinoma: a NSQIP Analysis.

BACKGROUND: Venous thromboembolism (VTE) remains a persistent source of postoperative morbidity despite prevention and mitigation efforts. Cancer, surgery, and chemotherapy are known risk factors for VTE. Existing literature suggests that neoadjuvant therapy (NAT) may contribute to increased VTE risk in the postoperative period, but few authors specifically examine this relationship in distal pancreatic adenocarcinoma (PDAC). In this study, we analyze the association of NAT and postoperative VTE in patients who underwent distal pancreatectomy (DP) for PDAC. PATIENTS AND METHODS: Using the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database, we analyzed the Procedure Targeted files for pancreatectomy from 2014 to 2020. Adults with PDAC who underwent DP were grouped by receipt of NAT. The primary outcome was the rate of deep venous thrombosis (DVT) and the secondary outcome was the rate of pulmonary embolism (PE). We performed univariate and multivariate logistic regression analysis to determine risk factors associated with postoperative DVT. RESULTS: There were 4327 patients with PDAC who underwent DP. Of these, 1414 (32.7%) had NAT. Receipt of NAT was significantly associated with postoperative DVT requiring therapy (3.5% vs. 2.3%, p = 0.02), but was not associated with PE (p = 0.42). On MVA, NAT was associated with a 73% greater chance of developing postoperative DVT [odds ratio (OR) 1.73, 95% CI 1.18-2.55]. CONCLUSIONS: Patients who receive NAT prior to DP for PDAC are 73% more likely to develop postoperative DVT compared with upfront resection. As NAT becomes more commonplace, these high-risk patients should be prioritized for guideline-recommended extended duration prophylaxis.

Plasma Ceramide C24:0/C16:0 Ratio is Associated with Improved Survival in Patients with Pancreatic Ductal Adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) has a high fatality rate, with surgery as the only curative treatment. Identification of new biomarkers related to survival may help guide discovery of new pathophysiologic pathways and potential therapeutic targets. As long-chain ceramides have been linked to tumor proliferation, we sought to determine if ceramide levels were prognostic in PDAC. METHODS: Patients from two phase I studies of PDAC were followed for all-cause mortality. Ceramide levels (C24:0, C22:0, and C16:0) were quantified before treatment and at study intervals. Multivariable Cox regression models assessed the association of ceramide levels and mortality after adjusting for other univariable predictors, including time-dependent tumor resection. The ability of repeated ceramide measures to discriminate patients at risk for mortality was also assessed using multivariable modeling and the c-statistic. RESULTS: Higher plasma C16:0 concentration was associated with higher all-cause mortality in univariable and multivariable analysis (adjusted hazard ratio [aHR] 1.41, 95% confidence interval [CI] 1.09-1.82; p < 0.01). In contrast, a higher plasma C24:0/C16:0 ratio was associated with lower all-cause mortality in multivariable analysis (aHR 0.69, 95% CI 0.49-0.97; p = 0.032). Discrimination of mortality was significantly improved with the addition of either plasma C16:0 or C24:0/C16:0 levels, with optimal discrimination occurring using repeated measures of the C24:0/C16:0 ratio (c-statistic 0.73 vs. c-statistic 0.66; p < 0.001). CONCLUSIONS: Higher plasma C16:0 and lower C24:0/C16:0 ratios are independently associated with mortality in PDAC and show an ability to improve discrimination of mortality in this deadly disease. Further studies are needed to confirm this association and evaluate this novel pathway for potential therapeutic targets.

Comparison of permitted daily exposure (PDE) values for active pharmaceutical ingredients (APIs) - Evidence of a robust approach.

Permitted Daily Exposure Limits (PDEs) are set for Active Pharmaceutical Ingredients (APIs) to control cross-contamination when manufacturing medicinal products in shared facilities. With the lack of official PDE lists for pharmaceuticals, PDEs have to be set by each company separately. Although general rules and guidelines for the setting of PDEs exist, inter-company variations in the setting of PDEs occur and are considered acceptable within a certain range. To evaluate the robustness of the PDE approach between different pharmaceutical companies, data on PDE setting of five marketed APIs (amlodipine, hydrochlorothiazide, metformin, morphine, and omeprazole) were collected and compared. Findings show that the variability between PDE values is within acceptable ranges (below 10-fold) for all compounds, with the highest difference for morphine due to different Point of Departures (PODs) and Adjustment Factors (AFs). Factors of PDE variability identified and further discussed are: (1) availability of data, (2) selection of POD, (3) assignment of AFs, (4) route-to-route extrapolation, and (5) expert judgement and differences in company policies. We conclude that the investigated PDE methods and calculations are robust and scientifically defensible. Additionally, we provide further recommendations to harmonize PDE calculation approaches across the pharmaceutical industry.

Induction of cancer neoantigens facilitates development of clinically relevant models for the study of pancreatic cancer immunobiology.

Neoantigen burden and CD8 T cell infiltrate are associated with clinical outcome in pancreatic ductal adenocarcinoma (PDAC). A shortcoming of many genetic models of PDAC is the lack of neoantigen burden and limited T cell infiltrate. The goal of the present study was to develop clinically relevant models of PDAC by inducing cancer neoantigens in KP2, a cell line derived from the KPC model of PDAC. KP2 was treated with oxaliplatin and olaparib (OXPARPi), and a resistant cell line was subsequently cloned to generate multiple genetically distinct cell lines (KP2-OXPARPi clones). Clones A and E are sensitive to immune checkpoint inhibition (ICI), exhibit relatively high T cell infiltration, and have significant upregulation of genes involved in antigen presentation, T cell differentiation, and chemokine signaling pathways. Clone B is resistant to ICI and is similar to the parental KP2 cell line in terms of relatively low T cell infiltration and no upregulation of genes involved in the pathways noted above. Tumor/normal exome sequencing and in silico neoantigen prediction confirms successful generation of cancer neoantigens in the KP2-OXPARPi clones and the relative lack of cancer neoantigens in the parental KP2 cell line. Neoantigen vaccine experiments demonstrate that a subset of candidate neoantigens are immunogenic and neoantigen synthetic long peptide vaccines can restrain Clone E tumor growth. Compared to existing models, the KP2-OXPARPi clones better capture the diverse immunobiology of human PDAC and may serve as models for future investigations in cancer immunotherapies and strategies targeting cancer neoantigens in PDAC.

NCCN Guidelines® Insights: Biliary Tract Cancers, Version 2.2023.

In 2023, the NCCN Guidelines for Hepatobiliary Cancers were divided into 2 separate guidelines: Hepatocellular Carcinoma and Biliary Tract Cancers. The NCCN Guidelines for Biliary Tract Cancers provide recommendations for the evaluation and comprehensive care of patients with gallbladder cancer, intrahepatic cholangiocarcinoma, and extrahepatic cholangiocarcinoma. The multidisciplinary panel of experts meets at least on an annual basis to review requests from internal and external entities as well as to evaluate new data on current and emerging therapies. These Guidelines Insights focus on some of the recent updates to the NCCN Guidelines for Biliary Tract Cancers as well as the newly published section on principles of molecular testing.

Ampullary Adenocarcinoma, Version 1.2023, NCCN Clinical Practice Guidelines in Oncology.

Ampullary cancers refer to tumors originating from the ampulla of Vater (the ampulla, the intraduodenal portion of the bile duct, and the intraduodenal portion of the pancreatic duct), while periampullary cancers may arise from locations encompassing the head of the pancreas, distal bile duct, duodenum, or ampulla of Vater. Ampullary cancers are rare gastrointestinal malignancies, and prognosis varies greatly based on factors such as patient age, TNM classification, differentiation grade, and treatment modality received. Systemic therapy is used in all stages of ampullary cancer, including neoadjuvant therapy, adjuvant therapy, and first-line or subsequent-line therapy for locally advanced, metastatic, and recurrent disease. Radiation therapy may be used in localized ampullary cancer, sometimes in combination with chemotherapy, but there is no high-level evidence to support its utility. Select tumors may be treated surgically. This article describes NCCN recommendations regarding management of ampullary adenocarcinoma.

Similar Responses in the Akt/Protein Kinase B Signaling Pathway Following Different Lower-Body Exercise Volumes in Recreationally Active Men.

ABSTRACT: Pearson, JR, Moodie, N, Stout, KW, Hawkins, WC, Matuszek, M, Graham, ZA, Siedlik, JA, Vardiman, JP, and Gallagher, PM. Similar responses in the Akt/protein kinase B (PKB) signaling pathway after different lower-body exercise volumes in recreationally active men. J Strength Cond Res 37(5): 1034-1041, 2023-This project examined the differences between a single set (SS) compared to multiple sets (MS) of resistance exercise on the Akt/protein kinase B (PKB) signaling pathway, the expression of insulin-like growth factor-1 ( IGF-1 ), and the receptor for IGF -1 ( IGF-1R ) to better understand the types of resistance training protocols that are most beneficial in stimulating the muscle hypertrophic response. Sixteen healthy men were randomly selected into 2 groups of 8. Subjects in each group received 3 biopsies: (a) before exercise, (b) 15 minutes postexercise, and (c) 180 minutes postexercise. Subjects in the SS group performed 1 set of leg press to failure at 80% of their predetermined 1 repetition maximum (1RM). Subjects in the MS group performed 2 sets of 10 repetitions and 1 set to failure at 80% of their predetermined 1RM, with 3 minutes of rest between each set. Our results indicated no group × time interactions in the concentration of Akt signaling proteins. Furthermore, there were no group × time interactions in IGF-1 or IGF-1R expression. However, phosphorylated 4E-binding protein 1 levels increased 150% from pre to 180 minutes post ( p = 0.005). In addition, there was a significantly greater increase in IGF-1R expression in the SS group compared with the MS group (7.99 ± 10.07 vs. 4.41 ± 6.28; p = 0.026). Collectively, we found that a SS of resistance training evokes a similar acute Akt/PKB pathway response as MS in recreationally active men.

Postoperative Proton Pump Inhibitors are associated with a significantly higher rate of delayed gastric emptying after pancreatoduodenectomy.

BACKGROUND: Proton pump inhibitors (PPIs) are effective in reducing marginal ulcers after pancreatoduodenectomy. However, their impact on perioperative complications has not been defined. METHODS: We retrospectively analyzed the effect of postoperative PPIs on 90-day perioperative outcomes in all patients who underwent pancreatoduodenectomy at our institution from April 2017 to December 2020. RESULTS: 284 patients were included; 206 (72.5%) received perioperative PPIs, 78 (27.5%) did not. The two cohorts were similar in demographics and operative variables. Postoperatively, the PPI cohort had significantly higher rates of overall complications (74.3% vs. 53.8%) and delayed gastric emptying (28.6% vs. 11.5%), p < 0.05. However, no differences in infectious complications, postoperative pancreatic fistula, or anastomotic leaks were seen. On multivariate analysis, PPI was independently associated with a higher risk of overall complications (OR 2.46, CI 1.33-4.54) and delayed gastric emptying (OR 2.73, CI 1.26-5.91), p = 0.011. Four patients developed marginal ulcers within 90-days postoperatively; all were in the group who received PPIs. CONCLUSION: Postoperative proton pump inhibitor use was associated with a significantly higher rate of overall complications and delayed gastric emptying after pancreatoduodenectomy.

Area deprivation and rurality impact overall survival and adjuvant therapy administration in patients with pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND: The impact of neighborhood deprivation on outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) is not well-described and represents an area to improve disparities. METHODS: We retrospectively queried our prospectively maintained database of patients with PDAC (2014-2022). Patients were grouped by Area Deprivation Index (ADI) and rural-urban commuting area (RUCA) codes. Cox proportional hazards models and logistic regressions were used to investigate effect on overall survival (OS) and adjuvant therapy administration. RESULTS: 536 patients were included. High ADI patients (more disadvantaged, n = 184) were more likely to identify as non-Hispanic Black (17.9% vs. 4.8%, p < 0.01) and were more likely to be from rural areas (49.5% vs. 18.5%, p < 0.01). High ADI was independently associated with decreased OS (HR (95% CI): 1.31 (1.01-1.69), p = 0.04). Urban high ADI patients were 3.5 times more likely to receive adjuvant therapy than rural high ADI patients (OR [95% CI]: 3.48 [1.26-9.61], p = 0.02). CONCLUSION: Patients from the most disadvantaged neighborhoods have decreased OS. Access to adjuvant therapy likely contributes to this disparity in rural areas. Investigation into sources of this OS disparity and identification of barriers to adjuvant therapy will be crucial to improve outcomes in underserved patients with PDAC.

4,300 steps per day prior to surgery are associated with improved outcomes after pancreatectomy.

BACKGROUND: Decreased preoperative physical fitness and low physical activity have been associated with preoperative functional reserve and surgical complications. We sought to evaluate daily step count as a measure of physical activity and its relationship with post-pancreatectomy outcomes. METHODS: Patients undergoing pancreatectomy were given a remote telemonitoring device to measure their preoperative levels of physical activity. Patient activity, demographics, and perioperative outcomes were collected and compared in univariate and multivariate logistic regression analysis. RESULTS: 73 patients were included. 45 (61.6%) patients developed complications, with 17 (23.3%) of those patients developing severe complications. These patients walked 3437.8 (SD 1976.7) average daily steps, compared to 5918.8 (SD 2851.1) in patients without severe complications (p < 0.001). In logistic regression analysis, patients who walked less than 4274.5 steps had significantly higher odds of severe complications (OR = 7.5 (CI 2.1, 26.8), p = 0.002). CONCLUSION: Average daily steps below 4274.5 before surgery are associated with severe complications after pancreatectomy. Preoperative physical activity levels may represent a modifiable target for prehabilitation protocols.

Increased Morbidity and Mortality After Hepatectomy for Colorectal Liver Metastases in Frail Patients is Largely Driven by Worse Outcomes After Minor Hepatectomy: It's Not "Just a Wedge".

BACKGROUND: Frailty is associated with postoperative mortality, but its significance after hepatectomy for colorectal liver metastases (CRLM) is poorly defined. This study evaluated the impact of frailty after hepatectomy for CRLM. METHODS: The study identified 8477 patients in National Surgical Quality Improvement Program databases from 2014 to 2019 and stratified them by frailty score using the risk analysis index as very frail (>90th percentile), frail (75th-90th percentile), or non-frail (< 75th percentile). Multivariate regression models determined the impact of frailty on perioperative outcomes, including by the extent of hepatectomy. RESULTS: The procedures performed were 2752 major hepatectomies (left hepatectomy, right hepatectomy, trisectionectomy) and 5725 minor hepatectomies (≤2 segments) for 870 (10.3%) very frail, 1680 (19.8%) frail, and 5927 (69.9%) non-frail patients. Postoperatively, the very frail and frail patients experienced more complications (very frail [41.8%], frail [35.1%], non-frail [31.0%]), which resulted in a longer hospital stay (very-frail [5.7 days], frail [5.8 days], non-frail [5.1 days]), a higher 30-day mortality (very-frail [2.2%], frail [1.3%], non-frail [0.5%]), and more discharges to a facility (very frail [6.8%], frail [3.7%], non-frail [2.6%]) (p < 0.05) although they underwent similarly extensive (major vs. minor) hepatectomies. In the multivariate analysis, frailty was independently associated with complications (very-frail [odds ratio {OR}, 1.70], frail [OR, 1.25]) and 30-day mortality (very-frail [OR, 4.24], frail [OR, 2.41]) (p < 0.05). After minor hepatectomy, the very frail and frail patients had significantly higher rates of complications and 30-day mortality than the non-frail patients, and in the multivariate analysis, frailty was independently associated with complications (very frail [OR, 1.97], frail [OR, 1.27]) and 30-day mortality (very frail [OR, 6.76], frail [OR, 3.47]) (p < 0.05) after minor hepatectomy. CONCLUSIONS: Frailty predicted significantly poorer outcomes after hepatectomy for CRLM, even after only a minor hepatectomy.

Development of a Prognostic Nomogram and Nomogram Software Application Tool to Predict Overall Survival and Disease-Free Survival After Curative-Intent Gastrectomy for Gastric Cancer.

BACKGROUND: We sought to derive and validate a prediction model of survival and recurrence among Western patients undergoing resection of gastric cancer. METHODS: Patients who underwent curative-intent surgery for gastric cancer at seven US institutions and a major Italian center from 2000 to 2020 were included. Variables included in the multivariable Cox models were identified using an automated model selection procedure based on an algorithm. Best models were selected using the Bayesian information criterion (BIC). The performance of the models was internally cross-validated via the bootstrap resampling procedure. Discrimination was evaluated using the Harrell's Concordance Index and accuracy was evaluated using calibration plots. Nomograms were made available as online tools. RESULTS: Overall, 895 patients met inclusion criteria. Age (hazard ratio [HR] 1.47, 95% confidence interval [CI] 1.17-1.84), presence of preoperative comorbidities (HR 1.66, 95% CI 1.14-2.41), lymph node ratio (LNR; HR 1.72, 95% CI 1.42-2.01), and lymphovascular invasion (HR 1.81, 95% CI 1.33-2.45) were associated with overall survival (OS; all p < 0.01), whereas tumor location (HR 1.93, 95% CI 1.23-3.02), T category (Tis-T1 vs. T3: HR 0.31, 95% CI 0.14-0.66), LNR (HR 1.82, 95% CI 1.45-2.28), and lymphovascular invasion (HR 1.49; 95% CI 1.01-2.22) were associated with disease-free survival (DFS; all p < 0.05) The models demonstrated good discrimination on internal validation relative to OS (C-index 0.70) and DFS (C-index 0.74). CONCLUSIONS: A web-based nomograms to predict OS and DFS among gastric cancer patients following resection demonstrated good accuracy and discrimination and good performance on internal validation.

The targeted SMAC mimetic SW IV-134 augments platinum-based chemotherapy in pre-clinical models of ovarian cancer.

BACKGROUND: Ovarian cancer is initially responsive to frontline chemotherapy. Unfortunately, it often recurs and becomes resistant to available therapies and the survival rate for advanced and recurrent ovarian cancer is unacceptably low. We thus hypothesized that it would be possible to achieve more durable treatment responses by combining cisplatin chemotherapy with SW IV-134, a cancer-targeted peptide mimetic and inducer of cell death. SW IV-134 is a recently developed small molecule conjugate linking a sigma-2 ligand with a peptide analog (mimetic) of the intrinsic death pathway activator SMAC (second-mitochondria activator of caspases). The sigma-2 receptor is overexpressed in ovarian cancer and the sigma-2 ligand portion of the conjugate facilitates cancer selectivity. The effector portion of the conjugate is expected to synergize with cisplatin chemotherapy and the cancer selectivity is expected to reduce putative off-target toxicities. METHODS: Ovarian cancer cell lines were treated with cisplatin alone, SW IV-134 alone and a combination of the two drugs. Treatment efficacy was determined using luminescent cell viability assays. Caspase-3/7, - 8 and - 9 activities were measured as complementary indicators of death pathway activation. Syngeneic mouse models and patient-derived xenograft (PDX) models of human ovarian cancer were studied for response to SW IV-134 and cisplatin monotherapy as well as combination therapy. Efficacy of the therapy was measured by tumor growth rate and survival as the primary readouts. Potential drug related toxicities were assessed at necropsy. RESULTS: The combination treatment was consistently superior in multiple cell lines when compared to the single agents in vitro. The expected mechanism of tumor cell death, such as caspase activation, was confirmed using luminescent and flow cytometry-based assay systems. Combination therapy proved to be superior in both syngeneic and PDX-based murine models of ovarian cancer. Most notably, combination therapy resulted in a complete resolution of established tumors in all study animals in a patient-derived xenograft model of ovarian cancer. CONCLUSIONS: The addition of SW IV-134 in combination with cisplatin chemotherapy represents a promising treatment option that warrants further pre-clinical development and evaluation as a therapy for women with advanced ovarian cancer.

Cause and outcome of aborting a difficult laparoscopic cholecystectomy due to severe inflammation: a study of operative notes.

BACKGROUND: Upon encountering a difficult cholecystectomy in which, after a reasonable trial of dissection, anatomical identification has not been attained due to severe inflammation, and the risk of additional dissection is deemed to be hazardous, "bail-out" strategies are encouraged safety valves. One strategy is to abort the cholecystectomy and refer the patient to a HPB center for further management. METHODS: A retrospective review was conducted of cholecystectomies performed by HPB surgeons at our center between 2005 and 2019. We identified 63 patients who had an aborted cholecystectomy because of acute or chronic cholecystitis and were referred for additional care. Of these, operative notes and other clinical records were available for 43 patients who were included in this study. RESULTS: 42 cholecystectomies (98%) were started laparoscopically. 25 patients (58%) had chronic cholecystitis, and 18 (42%) had acute cholecystitis. 40 cases (93%) fell into the highest level of difficulty on the Nassar scale (Grade 4). Procedures were aborted at the following stages of dissection: in 10 patients (23%), none of the gallbladder was identified; in another 11 (26%), only the dome of gallbladder was identified; the body of the gallbladder was exposed in 13 (30%); and dissection of the hepatocystic triangle was attempted unsuccessfully in 9 (21%). Following referral to our center, 30 patients (70%) were managed with total cholecystectomy while in 13 cases (30%), subtotal cholecystectomy was performed. CONCLUSION: Aborting cholecystectomy and referring the patient to an HPB center is rarely needed but is an effective bail-out strategy for general surgeons encountering highly difficult operative conditions due to inflammation.

Improved outcomes with minimally invasive pancreaticoduodenectomy in patients with dilated pancreatic ducts: a prospective study.

BACKGROUND: Little is known about what factors predict better outcomes for patients who undergo minimally invasive pancreaticoduodenectomy (MIPD) versus open pancreaticoduodenectomy (OPD). We hypothesized that patients with dilated pancreatic ducts have improved postoperative outcomes with MIPD compared to OPD. METHODS: All patients undergoing pancreaticoduodenectomy were prospectively followed over a time period of 47 months, and perioperative and pathologic covariates and outcomes were compared. Ideal outcome after PD was defined as follows: (1) no complications, (2) postoperative length of stay < 7 days, and (3) negative (R0) margins on pathology. Patients with dilated pancreatic ducts (≥ 3 mm) who underwent MIPD were 1:3 propensity score-matched to patients with dilated ducts who underwent OPD and outcomes compared. Likewise, patients with non-dilated pancreatic ducts (< 3 mm) who underwent MIPD were 1:3 propensity score-matched to patients with non-dilated ducts who underwent OPD and outcomes were compared. RESULTS: 371 patients underwent PD-74 (19.9%) MIPD and 297 (80.1%) underwent OPD. Overall, patients who underwent MIPD had significantly less intraoperative blood loss. After 1:3 propensity score matching, patients with dilated pancreatic ducts who underwent MIPD (n = 45) had significantly lower overall complication and 90-day readmission rates compared to matched OPD patients (n = 135) with dilated ducts. Patients with dilated duct who underwent MIPD were more likely to have an ideal outcome than patients with OPD (29 vs 15%, p = 0.035). There were no significant differences in postoperative outcomes among propensity score-matched patients with non-dilated pancreatic ducts who underwent MIPD (n = 29) compared to matched patients undergoing OPD (n = 87) with non-dilated ducts. CONCLUSIONS: MIPD is safe with comparable perioperative outcomes to OPD. Patients with pancreatic ducts ≥ 3 mm appear to derive the most benefit from MIPD in terms of fewer complications, lower readmission rates, and higher likelihood of ideal outcome.

Evaluation of the predictivity of Acute Oral Toxicity (AOT) structure-activity relationship models.

Several public efforts are aimed at discovering patterns or classifiers in the high-dimensional bioactivity space that predict tissue, organ or whole animal toxicological endpoints. The current study sought to assess and compare the predictions of the Globally Harmonized System (GHS) categories and Dangerous Goods (DG) classifications based on Lethal Dose (LD50) from several available tools (ACD/Labs, Leadscope, T.E.S.T., CATMoS, CaseUltra). External validation was done using dataset of 375 substances to demonstrate their predictive capacity. All models showed very good performance for identifying non-toxic compounds, which would be useful for DG classification, developing or triaging new chemicals, prioritizing existing chemicals for more detailed and rigorous toxicity assessments, and assessing non-active pharmaceutical intermediates. This would ultimately reduce animal use and improve risk assessments. Category-to-category prediction was not optimal, mainly due to the tendency to overpredict the outcome and the general limitations of acute oral toxicity (AOT) in vivo studies. Overprediction does not specifically pose a risk to human health, it can impact transport and material packaging requirements. Performance for compounds with LD50 ≤ 300 mg/kg (approx. 5% of the dataset) was the poorest among all groups and could be potentially improved by including expert review and read-across to similar substances.

Enhanced recovery pathway after open pancreaticoduodenectomy reduces postoperative length of hospital stay without reducing composite length of stay.

BACKGROUND/PURPOSE: There is no data regarding the impact of enhanced recovery pathways (ERP) on composite length of stay (CLOS) after procedures with increased risk of morbidity and mortality, such as pancreaticoduodenectomy. METHODS: Patients undergoing open pancreaticoduodenectomy before and after implementation of ERP were prospectively followed for 90 days after surgery and complications were severity graded using the Modified Accordion Grading System. A retrospective analysis of patient outcomes were compared before and after instituting ERP. 1:1 propensity score matching was used to compare ERP patient outcomes to those of matched pre-ERP patients. CLOS is defined as postoperative length of hospital stay (PLOS) plus readmission length of hospital stay within 90 days after surgery. RESULTS: 494 patients underwent open pancreaticoduodenectomy - 359 pre-ERP and 135 ERP. In a 1:1 propensity-score-matched analysis of 110 matched pairs, ERP patients had significantly decreased superficial surgical site infections (5.5% vs 15.5% p = 0.015) and significantly increased rates of urinary retention (29.1% vs 7.3% p < 0.0001) compared to matched pre-ERP patients. However, overall complication rate and 90-day readmission rate were not significantly different between matched groups. Propensity score-matched ERP patients had significantly decreased PLOS (7 days vs 8 days p = 0.046) compared to matched pre-ERP patients, but CLOS was not significantly different (9 days vs 9.5 days p = 0.615). CONCLUSION: ERP may reduce PLOS but might not impact the total postoperative time spent in the hospital (i.e. CLOS) within 90 days after pancreaticoduodenectomy.