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Dive into the research topics where George A. Poultsides is active.

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Featured researches published by George A. Poultsides.


Cell | 2011

An HNF4α-miRNA Inflammatory Feedback Circuit Regulates Hepatocellular Oncogenesis

Maria Hatziapostolou; Christos Polytarchou; Eleni Aggelidou; Alexandra Drakaki; George A. Poultsides; Savina Jaeger; Hisanobu Ogata; Michael Karin; Kevin Struhl; Margarita Hadzopoulou-Cladaras; Dimitrios Iliopoulos

Hepatocyte nuclear factor 4α (HNF4α) is essential for liver development and hepatocyte function. Here, we show that transient inhibition of HNF4α initiates hepatocellular transformation through a microRNA-inflammatory feedback loop circuit consisting of miR-124, IL6R, STAT3, miR-24, and miR-629. Moreover, we show that, once this circuit is activated, it maintains suppression of HNF4α and sustains oncogenesis. Systemic administration of miR-124, which modulates inflammatory signaling, prevents and suppresses hepatocellular carcinogenesis by inducing tumor-specific apoptosis without toxic side effects. As we also show that this HNF4α circuit is perturbed in human hepatocellular carcinomas, our data raise the possibility that manipulation of this microRNA feedback-inflammatory loop has therapeutic potential for treating liver cancer.Hepatocyte nuclear factor 4α (HNF4α) is essential for liver development and hepatocyte function. Here, we show that transient inhibition of HNF4α initiates hepatocellular transformation through a microRNA-inflammatory feedback loop circuit consisting of miR-124, IL6R, STAT3, miR-24, and miR-629. Moreover, we show that, once this circuit is activated, it maintains suppression of HNF4α and sustains oncogenesis. Systemic administration of miR-124, which modulates inflammatory signaling, prevents and suppresses hepatocellular carcinogenesis by inducing tumor-specific apoptosis without toxic side effects. As we also show that this HNF4α circuit is perturbed in human hepatocellular carcinomas, our data raise the possibility that manipulation of this microRNA feedback-inflammatory loop has therapeutic potential for treating liver cancer.


Journal of Clinical Oncology | 2009

Outcome of Primary Tumor in Patients With Synchronous Stage IV Colorectal Cancer Receiving Combination Chemotherapy Without Surgery As Initial Treatment

George A. Poultsides; Elliot L. Servais; Leonard Saltz; Sujata Patil; Nancy E. Kemeny; Jose G. Guillem; Martin R. Weiser; Larissa K. Temple; W. Douglas Wong; P. Paty

CRA4030 The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology. [Table: see text].PURPOSE The purpose of this study was to describe the frequency of interventions necessary to palliate the intact primary tumor in patients who present with synchronous, stage IV colorectal cancer (CRC) and who receive up-front modern combination chemotherapy without prophylactic surgery. PATIENTS AND METHODS By using a prospective institutional database, we identified 233 consecutive patients from 2000 through 2006 with synchronous metastatic CRC and an unresected primary tumor who received oxaliplatin- or irinotecan-based, triple-drug chemotherapy (infusional fluorouracil, leucovorin, and oxaliplatin; bolus fluorouracil, leucovorin, and irinotecan; or fluorouracil, leucovorin, and irinotecan) with or without bevacizumab as their initial treatment. The incidence of subsequent use of surgery, radiotherapy, and/or endoluminal stenting to manage primary tumor complications was recorded. RESULTS Of 233 patients, 217 (93%) never required surgical palliation of their primary tumor. Sixteen patients (7%) required emergent surgery for primary tumor obstruction or perforation, 10 patients (4%) required nonoperative intervention (ie, stent or radiotherapy), and 213 (89%) never required any direct symptomatic management for their intact primary tumor. Of those 213 patients, 47 patients (20%) ultimately underwent elective colon resection at the time of metastasectomy, and eight patients (3%) underwent this resection during laparotomy for hepatic artery infusion pump placement. Use of bevacizumab, location of the primary tumor in the rectum, and metastatic disease burden were not associated with increased intervention rate. CONCLUSION Most patients with synchronous, stage IV CRC who receive up-front modern combination chemotherapy never require palliative surgery for their intact primary tumor. These data support the use of chemotherapy, without routine prophylactic resection, as the appropriate standard practice for patients with neither obstructed nor hemorrhaging primary colorectal tumors in the setting of metastatic disease.


Annals of Surgery | 2010

Histopathologic basis for the favorable survival after resection of intraductal papillary mucinous neoplasm-associated invasive adenocarcinoma of the pancreas

George A. Poultsides; Sushanth Reddy; John L. Cameron; Ralph H. Hruban; Timothy M. Pawlik; Nita Ahuja; Ajay N. Jain; Barish H. Edil; Christine A. Iacobuzio-Donahue; Richard D. Schulick; Christopher L. Wolfgang

Objective:To identify pathologic features that may account for the favorable survival after resection of invasive pancreatic adenocarcinoma arising in the setting of intraductal papillary mucinous neoplasm (IPMN) compared with standard pancreatic ductal adenocarcinoma (PDA) in the absence of IPMN. Summary Background Data:The 5-year survival after resection of IPMN-associated invasive adenocarcinoma is reported to be between 40% and 60%, which is superior to the 10–25%, typically cited after resection of standard PDA. It remains unclear whether this represents distinct biology or simply a tendency for earlier presentation of IPMN-associated invasive adenocarcinoma. Methods:A single institutions prospective pancreatic resection database was retrospectively reviewed to identify patients with invasive pancreatic adenocarcinoma who underwent pancreatectomy with curative intent. Log rank and Cox regression analysis were used to identify factors associated with survival. Results:From 1995 to 2006, 1260 consecutive patients were identified, 132 (10%) with IPMN-associated invasive adenocarcinoma and 1128 (90%) with standard PDA. Actuarial 5-year survival was 42% after resection for IPMN-associated versus 19% for standard PDA (P < 0.001). However, compared with standard PDA, invasive adenocarcinoma arising within an IPMN was associated with a lower incidence of (1) advanced T stage (T2–T4, 96% vs. 73%, P < 0.001); (2) regional lymph node metastasis (78% vs. 51%, P < 0.001); (3) poor tumor differentiation (44% vs. 26%, P < 0.001); (4) vascular invasion (54% vs. 33%, P < 0.001); (5) perineural invasion (92% vs. 63%, P < 0.001); and (6) microscopic margin involvement (28% vs. 14%, P < 0.001). Specifically, in the presence of any one of the aforementioned adverse pathologic characteristics, outcomes after resection for IPMN-associated and standard PDA were not significantly different. Conclusion:The favorable biologic behavior of IPMN-associated compared with standard PDA is based on its lower rate of advanced T stage, lymph node metastasis, high tumor grade, positive resection margin, perineural, and vascular invasion. In the presence of any one of the aforementioned adverse pathologic characteristics, however, survival outcomes after resection of IPMN-associated and after resection of standard pancreatic adenocarcinoma are similar.


Proceedings of the National Academy of Sciences of the United States of America | 2014

Molecular assessment of surgical-resection margins of gastric cancer by mass-spectrometric imaging

Livia S. Eberlin; Robert Tibshirani; Jialing Zhang; Teri A. Longacre; Gerald J. Berry; David B. Bingham; Jeffrey A. Norton; Richard N. Zare; George A. Poultsides

Significance Complete resection of a tumor is associated with an improved prognosis for most types of solid malignancies. In gastric-cancer surgery, surgical-margin evaluation is commonly performed intraoperatively by histopathologic evaluation of frozen sections. However, frozen-section results are subjective and can be unreliable in up to 30% of patients undergoing resection of gastrointestinal cancers. We used desorption electrospray ionization mass spectrometric imaging (DESI-MSI) and the statistical method of least absolute shrinkage and selection operator (Lasso) to classify tissue as cancer or normal based on molecular information obtained from tissue and also to select those mass-spectra features most indicative of disease state. The results obtained using margin samples from nine gastric-cancer operations suggest that DESI-MSI/Lasso may be a valuable tool for routine intraoperative assessment of surgical margins during gastric-cancer surgery. Surgical resection is the main curative option for gastrointestinal cancers. The extent of cancer resection is commonly assessed during surgery by pathologic evaluation of (frozen sections of) the tissue at the resected specimen margin(s) to verify whether cancer is present. We compare this method to an alternative procedure, desorption electrospray ionization mass spectrometric imaging (DESI-MSI), for 62 banked human cancerous and normal gastric-tissue samples. In DESI-MSI, microdroplets strike the tissue sample, the resulting splash enters a mass spectrometer, and a statistical analysis, here, the Lasso method (which stands for least absolute shrinkage and selection operator and which is a multiclass logistic regression with L1 penalty), is applied to classify tissues based on the molecular information obtained directly from DESI-MSI. The methodology developed with 28 frozen training samples of clear histopathologic diagnosis showed an overall accuracy value of 98% for the 12,480 pixels evaluated in cross-validation (CV), and 97% when a completely independent set of samples was tested. By applying an additional spatial smoothing technique, the accuracy for both CV and the independent set of samples was 99% compared with histological diagnoses. To test our method for clinical use, we applied it to a total of 21 tissue-margin samples prospectively obtained from nine gastric-cancer patients. The results obtained suggest that DESI-MSI/Lasso may be valuable for routine intraoperative assessment of the specimen margins during gastric-cancer surgery.


Archives of Surgery | 2008

Angiographic Embolization for Gastroduodenal Hemorrhage: Safety, Efficacy, and Predictors of Outcome

George A. Poultsides; Christine J. Kim; Rocco Orlando; George Peros; Michael J. Hallisey; Paul V. Vignati

OBJECTIVE To examine the safety, efficacy, and predictors of outcome of angiographic embolization in the management of gastroduodenal hemorrhage. DESIGN Retrospective record review. SETTING University-affiliated tertiary care center. PATIENTS All of the patients were referred after endoscopic treatment failure. Surgery was not immediately considered because of poor surgical risk, refusal to consent, or endoscopists decision. Patients with coagulopathy, hemobilia, and variceal or traumatic upper gastrointestinal tract bleeding were excluded from review. INTERVENTIONS Between January 1, 1996, and December 31, 2006, 70 embolization procedures were performed in 57 patients. MAIN OUTCOME MEASURES Technical success rate (target vessel devascularization), clinical success rate (in-hospital cessation of bleeding without further endoscopic, radiologic, or surgical intervention), and complications. RESULTS The technical success rate was 94% (66 of 70 angiographies). The primary clinical success rate was 51% (29 of 57 patients), and the clinical success rate after repeat embolization was 56% (32 of 57 patients). Two factors were found to be independent predictors of poor outcome by multivariate analysis: recent duodenal ulcer suture ligation (P = .03) and blood transfusion of more than 6 units prior to the procedure (P = .04). There was no predictive value for angiographic failure based on age, sex, prior coagulopathy, renal failure at presentation, immunocompromised status, multiple organ system failure, empirical (blind) embolization, and use of permanent vs temporary embolic agents. Repeat embolizations were helpful for postsphincterotomy bleeding. Major ischemic complications (4 patients [7%]) were associated with previous foregut surgery. CONCLUSIONS Angiographic embolization for gastroduodenal hemorrhage was associated with in-hospital rebleeding in almost half of the patients. Angiographic failure can be predicted if embolization is performed late, following blood transfusion of more than 6 units, or for rehemorrhage from a previously suture-ligated duodenal ulcer.


Archives of Surgery | 2011

Pancreatic endocrine tumors with major vascular abutment, involvement, or encasement and indication for resection.

Jeffrey A. Norton; Edmund J. Harris; Yijun Chen; Brendan C. Visser; George A. Poultsides; Pamela C. Kunz; George A. Fisher; Robert T. Jensen

BACKGROUND Surgery for pancreatic endocrine tumors (PETs) with blood vessel involvement is controversial. HYPOTHESIS Resection of PETs with major blood vessel involvement can be beneficial. DESIGN The combined databases of the National Institutes of Health and Stanford University hospitals were queried. MAIN OUTCOME MEASURES Operation, pathologic condition, complications, and disease-free and overall survival. RESULTS Of 273 patients with PETs, 46 (17%) had preoperative computed tomography evidence of major vascular involvement. The mean size for the primary PET was 5.0 cm. The involved major vessel was as follows: portal vein (n = 20), superior mesenteric vein or superior mesenteric artery (n = 16), inferior vena cava (n = 4), splenic vein (n = 4), and heart (n = 2). Forty-two of 46 patients had a PET removed: 12 (27%) primary only, 30 (68%) with lymph nodes, and 18 (41%) with liver metastases. PETs were removed by either enucleation (n = 7) or resection (n = 35). Resections included distal or subtotal pancreatectomy in 23, Whipple in 10, and total in 2. Eighteen patients had concomitant liver resection: 10 wedge resection and 8 anatomic resections. Nine patients had vascular reconstruction: each had reconstruction of the superior mesenteric vein and portal vein, and 1 had concomitant reconstruction of the superior mesenteric artery. There were no deaths, but 12 patients had complications. Eighteen patients (41%) were immediately disease free, and 5 recurred with follow-up, leaving 13 (30%) disease-free long term. The 10-year overall survival was 60%. Functional tumors were associated with a better overall survival (P < .001), and liver metastases decreased overall survival (P < .001). CONCLUSION These findings suggest that surgical resection of PETs with vascular abutment/invasion and nodal or distant metastases is indicated.


Science Translational Medicine | 2016

Distinct biological subtypes and patterns of genome evolution in lymphoma revealed by circulating tumor DNA

Florian Scherer; David M. Kurtz; Aaron M. Newman; Henning Stehr; Alexander F.M. Craig; Mohammad Shahrokh Esfahani; Alexander F. Lovejoy; Jacob J. Chabon; Daniel M. Klass; Chih Long Liu; Li Zhou; Cynthia Glover; Brendan C. Visser; George A. Poultsides; Ranjana H. Advani; Lauren S. Maeda; Neel K. Gupta; Ronald Levy; Robert S. Ohgami; Christian A. Kunder; Maximilian Diehn; Ash A. Alizadeh

Circulating tumor DNA reveals patterns of clonal evolution and allows classification of tumor subtypes in lymphoma. The telltale DNA in lymphoma Diffuse large B cell lymphoma is a relatively common type of tumor that can exhibit a wide range of behaviors, from indolent and curable cancers to ones that are very aggressive and difficult to treat. By analyzing DNA in tumor samples and blood of lymphoma patients, Scherer et al. have shown that specific genetic characteristics can determine each tumor’s cell of origin and identify tumors that are going to transform into more aggressive subtypes and may require more intensive treatment. The authors also demonstrated that circulating tumor DNA in the patients’ blood is suitable for this analysis, allowing for periodic monitoring of each patient without repeated invasive biopsies. Patients with diffuse large B cell lymphoma (DLBCL) exhibit marked diversity in tumor behavior and outcomes, yet the identification of poor-risk groups remains challenging. In addition, the biology underlying these differences is incompletely understood. We hypothesized that characterization of mutational heterogeneity and genomic evolution using circulating tumor DNA (ctDNA) profiling could reveal molecular determinants of adverse outcomes. To address this hypothesis, we applied cancer personalized profiling by deep sequencing (CAPP-Seq) analysis to tumor biopsies and cell-free DNA samples from 92 lymphoma patients and 24 healthy subjects. At diagnosis, the amount of ctDNA was found to strongly correlate with clinical indices and was independently predictive of patient outcomes. We demonstrate that ctDNA genotyping can classify transcriptionally defined tumor subtypes, including DLBCL cell of origin, directly from plasma. By simultaneously tracking multiple somatic mutations in ctDNA, our approach outperformed immunoglobulin sequencing and radiographic imaging for the detection of minimal residual disease and facilitated noninvasive identification of emergent resistance mutations to targeted therapies. In addition, we identified distinct patterns of clonal evolution distinguishing indolent follicular lymphomas from those that transformed into DLBCL, allowing for potential noninvasive prediction of histological transformation. Collectively, our results demonstrate that ctDNA analysis reveals biological factors that underlie lymphoma clinical outcomes and could facilitate individualized therapy.


Archives of Surgery | 2012

Lymph Nodes and Survival in Pancreatic Neuroendocrine Tumors

Geoffrey W. Krampitz; Jeffrey A. Norton; George A. Poultsides; Brendan C. Visser; Lixian Sun; Robert T. Jensen

HYPOTHESIS Lymph node metastases decrease survival in patients with pancreatic neuroendocrine tumors (pNETs). DESIGN Prospective database searches. SETTING National Institutes of Health (NIH) and Stanford University Hospital (SUH). PATIENTS A total of 326 patients underwent surgical exploration for pNETs at the NIH (n = 216) and SUH (n = 110). MAIN OUTCOME MEASURES Overall survival, disease-related survival, and time to development of liver metastases. RESULTS Forty patients (12.3%) underwent enucleation and 305 (93.6%) underwent resection. Of the patients who underwent resection, 117 (35.9%) had partial pancreatectomy and 30 (9.2%) had a Whipple procedure. Forty-one patients also had liver resections, 21 had wedge resections, and 20 had lobectomies. Mean follow-up was 8.1 years (range, 0.3-28.6 years). The 10-year overall survival for patients with no metastases or lymph node metastases only was similar at 80%. As expected, patients with liver metastases had a significantly decreased 10-year survival of 30% (P < .001). The time to development of liver metastases was significantly reduced for patients with lymph node metastases alone compared with those with none (P < .001). For the NIH cohort with longer follow-up, disease-related survival was significantly different for those patients with no metastases, lymph node metastases alone, and liver metastases (P < .001). Extent of lymph node involvement in this subgroup showed that disease-related survival decreased as a function of the number of lymph nodes involved (P = .004). CONCLUSIONS As expected, liver metastases decrease survival of patients with pNETs. Patients with lymph node metastases alone have a shorter time to the development of liver metastases that is dependent on the number of lymph nodes involved. With sufficient long-term follow-up, lymph node metastases decrease disease-related survival. Careful evaluation of number and extent of lymph node involvement is warranted in all surgical procedures for pNETs.


Hpb | 2012

Failure to comply with NCCN guidelines for the management of pancreatic cancer compromises outcomes

Brendan C. Visser; Yifei Ma; Yulia Zak; George A. Poultsides; Jeffrey A. Norton; Kim F. Rhoads

INTRODUCTION There are little data available regarding compliance with the National Comprehensive Cancer Network (NCCN) guidelines. We investigated variation in the management of pancreatic cancer (PC) among large hospitals in California, USA, specifically to evaluate whether compliance with NCCN guidelines correlates with patient outcomes. METHODS The California Cancer Registry was used to identify patients treated for PC from 2001 to 2006. Only hospitals with ≥ 400 beds were included to limit evaluation to centres possessing resources to provide multimodality care (n= 50). Risk-adjusted multivariable models evaluated predictors of adherence to stage-specific NCCN guidelines for PC and mortality. RESULTS In all, 3706 patients were treated for PC in large hospitals during the study period. Compliance with NCCN guidelines was only 34.5%. Patients were less likely to get recommended therapy with advanced age and low socioeconomic status (SES). Using multilevel analysis, controlling for patient factors (including demographics and comorbidities), hospital factors (e.g. size, academic affiliation and case volume), compliance with NCCN guidelines was associated with a reduced risk of mortality [odds ratio (OR) for death 0.64 (0.53-0.77, P < 0.0001)]. CONCLUSIONS There is relatively poor overall compliance with the NCCN PC guidelines in Californias large hospitals. Higher compliance rates are correlated with improved survival. Compliance is an important potential measure of the quality of care.


Journal of The American College of Surgeons | 2014

Rates and patterns of recurrence after curative intent resection for gastric cancer: a United States multi-institutional analysis.

Gaya Spolverato; Aslam Ejaz; Yuhree Kim; Malcolm H. Squires; George A. Poultsides; Ryan C. Fields; Carl Schmidt; Sharon M. Weber; Konstantinos I. Votanopoulos; Shishir K. Maithel; Timothy M. Pawlik

BACKGROUND Reports on recurrence and outcomes of US patients with gastric cancer are scarce. The aim of this study was to determine incidence and pattern of recurrence after curative intent surgery for gastric cancer. STUDY DESIGN Using the multi-institutional US Gastric Cancer Collaborative database, we identified 817 patients undergoing curative intent resection for gastric cancer between 2000 and 2012. Patterns and rates of recurrence along with associated risk factors were identified using adjusted regression analysis. Recurrences were classified as locoregional, peritoneal, or hematogenous. RESULTS Median patient age was 65.8 years (interquartile range [IQR] 56.4, 74.7); the majority of patients were male (n = 462, 56.6%) and white (n = 511, 62.5%). At the time of surgery, the majority of patients underwent a partial gastrectomy (n = 481, 59.2%) with a complete R0 resection achieved in 91.6% (n = 748) of patients. At the time of last follow-up, 244 (29.9%) of 817 patients developed a recurrence; 163 (66.8%) patients had recurrence at only a single site; the remaining 81 (33.2%) had multiple sites of initial recurrence. Among patients who recurred at a single site, recurrence was most common at a distant location and included hematogenous (n = 57, 23.4%) or peritoneal (n = 47, 19.3%) only metastasis. Tumors at the gastroesophageal junction (odds ratio [OR] 3.18, 95% CI 1.08 to 9.40; p = 0.04) were associated with higher risk of locoregional recurrence, while the presence of multiple lesions (OR 10.82, 95% CI 3.56 to 32.85; p < 0.001) remained associated with an increased risk of distant hematogenous recurrence after adjusted analysis. Recurrence was associated with worse survival, with a median recurrence-free survival of 10.8 months (IQR 8.9, 12.8) among those who experienced a recurrence. CONCLUSIONS Nearly one-third of patients experienced recurrence after gastric cancer surgery. The most common site of recurrence was distant.

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Timothy M. Pawlik

The Ohio State University Wexner Medical Center

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Ryan C. Fields

Washington University in St. Louis

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Sharon M. Weber

University of Wisconsin-Madison

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Carl Schmidt

The Ohio State University Wexner Medical Center

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Linda X. Jin

Washington University in St. Louis

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