44 results on '"McAuliffe JC"'
Search Results
2. Cecal volvulus after robotic assisted laparoscopic hysterectomy in a gynecologic oncology patient: A case report.
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Gowthaman D, Scanlon L, McAuliffe JC, Fidvi S, Schwartz C, and Isani SS
- Abstract
Cecal volvulus is a rare and life-threatening cause of intestinal obstruction with multiple risk factors including prior abdominal surgery and cecal hypermobility. Although its incidence has been reported after common procedures such as cholecystectomy and appendectomy, it has not been well studied after laparoscopy, especially in gynecological surgeries. If untreated, a cecal volvulus can result in serious complications such as intestinal strangulation, necrosis, or perforation. Therefore, early identification of risk factors and intervention is important in prevention of these sequelae. Here, we report a case of cecal volvulus in a patient with endometrial carcinoma after a staging robotic-assisted laparoscopic hysterectomy and the risk factors that may have led to her complication., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Inc.)
- Published
- 2024
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3. Complications related to thyroidectomy among patients with hyperthyroidism: Exploring the potential for ambulatory surgery.
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Zhang FG, Ow TJ, Lin J, Smith RV, Schiff BA, DeBiase CA, McAuliffe JC, Bloomgarden N, and Mehta V
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- Humans, Female, Adult, Middle Aged, Male, Retrospective Studies, Thyroidectomy adverse effects, Ambulatory Surgical Procedures adverse effects, Inpatients, Postoperative Complications epidemiology, Postoperative Complications etiology, Thyroid Crisis complications, Vocal Cord Paralysis etiology
- Abstract
Background: Total thyroidectomy for hyperthyroidism is typically followed by overnight admission to monitor for complications including thyrotoxicosis. Outpatient thyroid surgery is increasingly common, but its safety in patients with hyperthyroidism has not been well studied., Methods: This retrospective study reviewed 183 patients with hyperthyroidism who underwent total thyroidectomy from 2015 to 2022 at one urban, academic center. The main outcomes were rates of thyroid storm, surgical complications, and 30-day ED visits and readmissions., Results: Among 183 patients with hyperthyroidism (mean age, 45 ± 14.5 years; 82.5% female), there were no cases of thyroid storm and complications included recurrent laryngeal nerve (RLN) palsy (7.0%), symptomatic hypocalcemia (4.4%), and hematoma (1.6%). ED visits were present in 1.1% and no patients were readmitted., Conclusion: Total thyroidectomy was not associated with thyroid storm and <6% of patients required inpatient management. Ambulatory total thyroidectomy for hyperthyroidism warrants further consideration through identification of predictive factors for postoperative complications., (© 2024 Wiley Periodicals LLC.)
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- 2024
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4. Signaling events at TMEM doorways provide potential targets for inhibiting breast cancer dissemination.
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Surve CR, Duran CL, Ye X, Chen X, Lin Y, Harney AS, Wang Y, Sharma VP, Stanley ER, Cox D, McAuliffe JC, Entenberg D, Oktay MH, and Condeelis JS
- Abstract
Tumor cell intravasation is essential for metastatic dissemination, but its exact mechanism is incompletely understood. We have previously shown that in breast cancer, the direct and stable association of a tumor cell expressing Mena, a Tie2
hi /VEGFhi macrophage, and a vascular endothelial cell, creates an intravasation portal, called a "tumor microenvironment of metastasis" (TMEM) doorway, for tumor cell intravasation, leading to dissemination to distant sites. The density of TMEM doorways, also called TMEM doorway score, is a clinically validated prognostic marker of distant metastasis in breast cancer patients. Although we know that tumor cells utilize TMEM doorway-associated transient vascular openings to intravasate, the precise signaling mechanisms involved in TMEM doorway function are only partially understood. Using two mouse models of breast cancer and an in vitro assay of intravasation, we report that CSF-1 secreted by the TMEM doorway tumor cell stimulates local secretion of VEGF-A from the Tie2hi TMEM doorway macrophage, leading to the dissociation of endothelial junctions between TMEM doorway associated endothelial cells, supporting tumor cell intravasation. Acute blockade of CSF-1R signaling decreases macrophage VEGF-A secretion as well as TMEM doorway-associated vascular opening, tumor cell trans-endothelial migration, and dissemination. These new insights into signaling events regulating TMEM doorway function should be explored further as treatment strategies for metastatic disease., Competing Interests: Competing interests: The authors declare no competing financial interests.- Published
- 2024
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5. Stabilized Window for Intravital Imaging of the Murine Pancreas.
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Petersen J, Du W, Adkisson C, Gravekamp C, Oktay MH, Condeelis J, Panarelli NC, McAuliffe JC, and Entenberg D
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- Humans, Animals, Mice, Acute Disease, Pancreas diagnostic imaging, Pancreas pathology, Intravital Microscopy methods, Pancreatic Neoplasms diagnostic imaging, Pancreatic Neoplasms pathology, Pancreatitis pathology, Adenocarcinoma pathology, Carcinoma, Pancreatic Ductal pathology
- Abstract
The physiology and pathophysiology of the pancreas are complex. Diseases of the pancreas, such as pancreatitis and pancreatic adenocarcinoma (PDAC) have high morbidity and mortality. Intravital imaging (IVI) is a powerful technique enabling the high-resolution imaging of tissues in both healthy and diseased states, allowing for real-time observation of cell dynamics. IVI of the murine pancreas presents significant challenges due to the deep visceral and compliant nature of the organ, which make it highly prone to damage and motion artifacts. Described here is the process of implantation of the Stabilized Window for Intravital imaging of the murine Pancreas (SWIP). The SWIP allows IVI of the murine pancreas in normal healthy states, during the transformation from the healthy pancreas to acute pancreatitis induced by cerulein, and in malignant states such as pancreatic tumors. In conjunction with genetically labeled cells or the administration of fluorescent dyes, the SWIP enables the measurement of single-cell and subcellular dynamics (including single-cell and collective migration) as well as serial imaging of the same region of interest over multiple days. The ability to capture tumor cell migration is of particular importance as the primary cause of cancer-related mortality in PDAC is the overwhelming metastatic burden. Understanding the physiological dynamics of metastasis in PDAC is a critical unmet need and crucial for improving patient prognosis. Overall, the SWIP provides improved imaging stability and expands the application of IVI in the healthy pancreas and malignant pancreas diseases.
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- 2023
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6. Piperacillin-Tazobactam Compared With Cefoxitin as Antimicrobial Prophylaxis for Pancreatoduodenectomy: A Randomized Clinical Trial.
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D'Angelica MI, Ellis RJ, Liu JB, Brajcich BC, Gönen M, Thompson VM, Cohen ME, Seo SK, Zabor EC, Babicky ML, Bentrem DJ, Behrman SW, Bertens KA, Celinski SA, Chan CHF, Dillhoff M, Dixon MEB, Fernandez-Del Castillo C, Gholami S, House MG, Karanicolas PJ, Lavu H, Maithel SK, McAuliffe JC, Ott MJ, Reames BN, Sanford DE, Sarpel U, Scaife CL, Serrano PE, Smith T, Snyder RA, Talamonti MS, Weber SM, Yopp AC, Pitt HA, and Ko CY
- Subjects
- Male, Adult, Humans, Aged, Piperacillin therapeutic use, Pancreaticoduodenectomy adverse effects, Pancreatic Fistula drug therapy, Penicillanic Acid therapeutic use, Anti-Bacterial Agents therapeutic use, Piperacillin, Tazobactam Drug Combination therapeutic use, Surgical Wound Infection prevention & control, Cefoxitin therapeutic use, Sepsis drug therapy
- Abstract
Importance: Despite improvements in perioperative mortality, the incidence of postoperative surgical site infection (SSI) remains high after pancreatoduodenectomy. The effect of broad-spectrum antimicrobial surgical prophylaxis in reducing SSI is poorly understood., Objective: To define the effect of broad-spectrum perioperative antimicrobial prophylaxis on postoperative SSI incidence compared with standard care antibiotics., Design, Setting, and Participants: Pragmatic, open-label, multicenter, randomized phase 3 clinical trial at 26 hospitals across the US and Canada. Participants were enrolled between November 2017 and August 2021, with follow-up through December 2021. Adults undergoing open pancreatoduodenectomy for any indication were eligible. Individuals were excluded if they had allergies to study medications, active infections, chronic steroid use, significant kidney dysfunction, or were pregnant or breastfeeding. Participants were block randomized in a 1:1 ratio and stratified by the presence of a preoperative biliary stent. Participants, investigators, and statisticians analyzing trial data were unblinded to treatment assignment., Intervention: The intervention group received piperacillin-tazobactam (3.375 or 4 g intravenously) as perioperative antimicrobial prophylaxis, while the control group received cefoxitin (2 g intravenously; standard care)., Main Outcomes and Measures: The primary outcome was development of postoperative SSI within 30 days. Secondary end points included 30-day mortality, development of clinically relevant postoperative pancreatic fistula, and sepsis. All data were collected as part of the American College of Surgeons National Surgical Quality Improvement Program., Results: The trial was terminated at an interim analysis on the basis of a predefined stopping rule. Of 778 participants (378 in the piperacillin-tazobactam group [median age, 66.8 y; 233 {61.6%} men] and 400 in the cefoxitin group [median age, 68.0 y; 223 {55.8%} men]), the percentage with SSI at 30 days was lower in the perioperative piperacillin-tazobactam vs cefoxitin group (19.8% vs 32.8%; absolute difference, -13.0% [95% CI, -19.1% to -6.9%]; P < .001). Participants treated with piperacillin-tazobactam, vs cefoxitin, had lower rates of postoperative sepsis (4.2% vs 7.5%; difference, -3.3% [95% CI, -6.6% to 0.0%]; P = .02) and clinically relevant postoperative pancreatic fistula (12.7% vs 19.0%; difference, -6.3% [95% CI, -11.4% to -1.2%]; P = .03). Mortality rates at 30 days were 1.3% (5/378) among participants treated with piperacillin-tazobactam and 2.5% (10/400) among those receiving cefoxitin (difference, -1.2% [95% CI, -3.1% to 0.7%]; P = .32)., Conclusions and Relevance: In participants undergoing open pancreatoduodenectomy, use of piperacillin-tazobactam as perioperative prophylaxis reduced postoperative SSI, pancreatic fistula, and multiple downstream sequelae of SSI. The findings support the use of piperacillin-tazobactam as standard care for open pancreatoduodenectomy., Trial Registration: ClinicalTrials.gov Identifier: NCT03269994.
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- 2023
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7. Domo arigato, Mr. Roboto.
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Romero-Velez G and McAuliffe JC
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- 2022
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8. SWIP-a stabilized window for intravital imaging of the murine pancreas.
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Du W, Adkisson C, Ye X, Duran CL, Chellakkan Selvanesan B, Gravekamp C, Oktay MH, McAuliffe JC, Condeelis JS, Panarelli NC, Norgard RJ, Sela Y, Stanger BZ, and Entenberg D
- Subjects
- Acute Disease, Animals, Intravital Microscopy, Mice, Pancreas diagnostic imaging, Pancreas pathology, Carcinoma, Pancreatic Ductal diagnostic imaging, Carcinoma, Pancreatic Ductal pathology, Pancreatic Neoplasms diagnostic imaging, Pancreatic Neoplasms pathology, Pancreatitis chemically induced, Pancreatitis diagnostic imaging, Pancreatitis pathology
- Abstract
Pancreatitis and pancreatic ductal adenocarcinoma (PDAC) are grave illnesses with high levels of morbidity and mortality. Intravital imaging (IVI) is a powerful technique for visualizing physiological processes in both health and disease. However, the application of IVI to the murine pancreas presents significant challenges, as it is a deep, compliant, visceral organ that is difficult to access, easily damaged and susceptible to motion artefacts. Existing imaging windows for stabilizing the pancreas during IVI have unfortunately shown poor stability for time-lapsed imaging on the minutes to hours scale, or are unable to accommodate both the healthy and tumour-bearing pancreata. To address these issues, we developed an improved stabilized window for intravital imaging of the pancreas (SWIP), which can be applied to not only the healthy pancreas but also to solid tumours like PDAC. Here, we validate the SWIP and use it to visualize a variety of processes for the first time, including (1) single-cell dynamics within the healthy pancreas, (2) transformation from healthy pancreas to acute pancreatitis induced by cerulein, and (3) the physiology of PDAC in both autochthonous and orthotopically injected models. SWIP can not only improve the imaging stability but also expand the application of IVI in both benign and malignant pancreas diseases.
- Published
- 2022
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9. A procedure for removal of cyanuric acid in swimming pools using a cell-free thermostable cyanuric acid hydrolase.
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Guo F, McAuliffe JC, Bongiorni C, Latone JA, Pepsin MJ, Chow MS, Dhaliwal RS, Hoffmann KM, Brazil BT, Heng MH, Robinson SL, Wackett LP, and Whited GM
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- Chlorine, Hydrolases genetics, Hydrolases metabolism, Hypochlorous Acid, Triazines, Biuret metabolism, Swimming Pools
- Abstract
Cyanuric acid (CYA) is used commercially for maintaining active chlorine to inactivate microbial and viral pathogens in swimming pools and hot tubs. Repeated CYA addition can cause a lack of available chlorine and adequate disinfection. Acceptable CYA levels can potentially be restored via cyanuric acid hydrolases (CAH), enzymes that hydrolyze CYA to biuret under mild conditions. Here we describe a previously unknown CAH enzyme from Pseudolabrys sp. Root1462 (CAH-PR), mined from public databases by bioinformatic analysis of potential CAH genes, which we show to be suitable in a cell-free form for industrial applications based upon favorable enzymatic and physical properties, combined with high-yield expression in aerobic cell culture. The kinetic parameters and modeled structure were similar to known CAH enzymes, but the new enzyme displayed a surprising thermal and storage stability. The new CAH enzyme was applied, following addition of inexpensive sodium sulfite, to hydrolyze CYA to biuret. At the desired endpoint, hypochlorite addition inactivated remaining enzyme and oxidized biuret to primarily dinitrogen and carbon dioxide gases. The mechanism of biuret oxidation with hypochlorite under conditions relevant to recreational pools is described., (© The Author(s) 2021. Published by Oxford University Press on behalf of Society of Industrial Microbiology and Biotechnology.)
- Published
- 2022
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10. Listeria delivers tetanus toxoid protein to pancreatic tumors and induces cancer cell death in mice.
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Selvanesan BC, Chandra D, Quispe-Tintaya W, Jahangir A, Patel A, Meena K, Alves Da Silva RA, Friedman M, Gabor L, Khouri O, Libutti SK, Yuan Z, Li J, Siddiqui S, Beck A, Tesfa L, Koba W, Chuy J, McAuliffe JC, Jafari R, Entenberg D, Wang Y, Condeelis J, DesMarais V, Balachandran V, Zhang X, Lin K, and Gravekamp C
- Subjects
- Animals, Cell Death, Disease Models, Animal, Mice, Tetanus Toxoid therapeutic use, Tumor Microenvironment, Carcinoma, Pancreatic Ductal pathology, Listeria, Pancreatic Neoplasms drug therapy
- Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease. Tumors are poorly immunogenic and immunosuppressive, preventing T cell activation in the tumor microenvironment. Here, we present a microbial-based immunotherapeutic treatment for selective delivery of an immunogenic tetanus toxoid protein (TT
856-1313 ) into PDAC tumor cells by attenuated Listeria monocytogenes . This treatment reactivated preexisting TT-specific memory T cells to kill infected tumor cells in mice. Treatment of KrasG12D,p53R172H, Pdx1-Cre (KPC) mice with Listeria -TT resulted in TT accumulation inside tumor cells, attraction of TT-specific memory CD4 T cells to the tumor microenvironment, and production of perforin and granzyme B in tumors. Low doses of gemcitabine (GEM) increased immune effects of Listeria -TT, turning immunologically cold into hot tumors in mice. In vivo depletion of T cells from Listeria -TT + GEM-treated mice demonstrated a CD4 T cell-mediated reduction in tumor burden. CD4 T cells from TT-vaccinated mice were able to kill TT-expressing Panc-02 tumor cells in vitro. In addition, peritumoral lymph node-like structures were observed in close contact with pancreatic tumors in KPC mice treated with Listeria -TT or Listeria -TT + GEM. These structures displayed CD4 and CD8 T cells producing perforin and granzyme B. Whereas CD4 T cells efficiently infiltrated the KPC tumors, CD8 T cells did not. Listeria -TT + GEM treatment of KPC mice with advanced PDAC reduced tumor burden by 80% and metastases by 87% after treatment and increased survival by 40% compared to nontreated mice. These results suggest that Listeria -delivered recall antigens could be an alternative to neoantigen-mediated cancer immunotherapy.- Published
- 2022
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11. MYC Levels Regulate Metastatic Heterogeneity in Pancreatic Adenocarcinoma.
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Maddipati R, Norgard RJ, Baslan T, Rathi KS, Zhang A, Saeid A, Higashihara T, Wu F, Kumar A, Annamalai V, Bhattacharya S, Raman P, Adkisson CA, Pitarresi JR, Wengyn MD, Yamazoe T, Li J, Balli D, LaRiviere MJ, Ngo TC, Folkert IW, Millstein ID, Bermeo J, Carpenter EL, McAuliffe JC, Oktay MH, Brekken RA, Lowe SW, Iacobuzio-Donahue CA, Notta F, and Stanger BZ
- Subjects
- Adenocarcinoma secondary, Animals, Carcinoma, Pancreatic Ductal secondary, Disease Models, Animal, Humans, Mice, Pancreatic Neoplasms pathology, Adenocarcinoma genetics, Carcinoma, Pancreatic Ductal genetics, Gene Expression Regulation, Neoplastic, Genes, myc, Neoplasm Metastasis, Pancreatic Neoplasms genetics
- Abstract
The degree of metastatic disease varies widely among patients with cancer and affects clinical outcomes. However, the biological and functional differences that drive the extent of metastasis are poorly understood. We analyzed primary tumors and paired metastases using a multifluorescent lineage-labeled mouse model of pancreatic ductal adenocarcinoma (PDAC)-a tumor type in which most patients present with metastases. Genomic and transcriptomic analysis revealed an association between metastatic burden and gene amplification or transcriptional upregulation of MYC and its downstream targets. Functional experiments showed that MYC promotes metastasis by recruiting tumor-associated macrophages, leading to greater bloodstream intravasation. Consistent with these findings, metastatic progression in human PDAC was associated with activation of MYC signaling pathways and enrichment for MYC amplifications specifically in metastatic patients. Collectively, these results implicate MYC activity as a major determinant of metastatic burden in advanced PDAC. SIGNIFICANCE: Here, we investigate metastatic variation seen clinically in patients with PDAC and murine PDAC tumors and identify MYC as a major driver of this heterogeneity. This article is highlighted in the In This Issue feature, p. 275 ., (©2021 The Authors; Published by the American Association for Cancer Research.)
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- 2022
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12. Cocreation of Virtual Online Poverty Simulations in Google Slides: An Interprofessional Collaboration Between Students and Their Professors.
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Killam LA, McAuliffe JC, Hutton SA, Lefebvre ME, Campbell EE, Robinson RP, and Ghartey K
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- Cooperative Behavior, Humans, Poverty, Students, Interprofessional Relations, Search Engine
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- 2022
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13. The Utility of Hepatobiliary Scintigraphy Scans in the Tokyo Guidelines Era for Acute Cholecystitis.
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Romero-Velez G, Pereira X, Mandujano CC, Parides MK, Muscarella P, Melvin WS, Love C, and McAuliffe JC
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- Humans, Male, Radionuclide Imaging, Retrospective Studies, Tokyo, Cholecystitis, Acute diagnostic imaging
- Abstract
Background: Hepatobiliary Scintigraphy (HIDA) aids the diagnosis of acute cholecystitis (AC) but has limitations. We sought to design a model based on the Tokyo Guidelines 2018 (TG18) to predict HIDA results., Methods: A retrospective review of patients who underwent a HIDA scan during the evaluation of AC was performed. Using logistic regression techniques incorporating the TG18 criterion and additional readily available patient characteristics, a prediction model was created to identify patients likely to test negative for acute cholecystitis by HIDA scan., Results: In 235 patients with suspected AC, a HIDA scan was performed. Variables associated with positive HIDA results were male gender (RR 2.0 (CI 1.33-2.99), age (OR 1.02 (CI 1.01-1.04), right upper quadrant tenderness (RR 1.7 (CI 1.1-2.8)), clinical Murphy's sign (RR 2.2 (CI 1.5-3.4)), ultrasound findings suggestive of AC by any of its components (RR 3.2 (CI 1.6-6.5)), gallbladder wall thickening (RR 2.0 (CI 1.3-3.1)), and gallbladder distention (RR 1.9 (CI 1.3-2.9)). These variables allowed for creation of a model to predict HIDA results. The model predicted HIDA results in 36.9% of patients with an area under the curve of 0.81., Conclusions: In the era of TG18, HIDA is probably over utilized. We developed an accurate, simple model based on TG18 that identifies a group of patients for whom a HIDA scan is unnecessary to establish the diagnosis of AC., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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14. Colorectal Cancer Surgery Outcomes in the Non-elective Setting: a Target for Improvement.
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Shanja-Grabarz X, McAuliffe JC, Kanneganti M, Friedmann P, Levine R, Huang R, and In H
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- Elective Surgical Procedures, Humans, Colorectal Neoplasms surgery, Digestive System Surgical Procedures
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- 2021
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15. SARS-CoV-2 During Abdominal Operations: Are Surgeons at Risk?
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Romero-Velez G, Rodriguez Quintero JH, Pereira X, Nussbaum JE, and McAuliffe JC
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- Adult, Cross-Sectional Studies, Humans, Peritoneum, Prospective Studies, SARS-CoV-2, COVID-19, Surgeons
- Abstract
Background: The safety of surgery in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients remains unclear. On the basis of data from other viral diseases, it has been assumed that coronavirus disease 2019 (COVID-19) has the potential risk of transmission during surgery. The presence of the virus within the peritoneal fluid and the peritoneal tissues is not known., Materials and Methods: This is a prospective cross-sectional study including adult patients with confirmed COVID-19 who underwent surgery at a single institution. Using specific real-time reverse transcriptase-polymerase chain reaction, the presence of SARS-CoV-2 was determined in abdominal fluid samples., Results: Six patients with COVID-19 underwent abdominal surgery. Five patients were asymptomatic, and 1 had severe disease. SARS-CoV-2 was tested in 20 different samples, all of which resulted negative., Conclusions: SARS-CoV-2 was not found in the peritoneal cavity of 6 patients undergoing abdominal surgery. The risk of transmissibility of COVID-19 during surgery is still unclear., Competing Interests: The author declares no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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16. Outcomes of Adrenalectomy and the Aldosteronoma Resolution Score in the Black and Hispanic Population.
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Romero-Velez G, Laird AM, Barajas ME, Sierra-Salazar M, Herrera MF, Libutti SK, Parides MK, Pereira X, and McAuliffe JC
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- Adrenalectomy, Black or African American, Aldosterone, Female, Hispanic or Latino, Humans, Retrospective Studies, Treatment Outcome, Adrenocortical Adenoma surgery, Hyperaldosteronism surgery, Hypertension surgery
- Abstract
Background: Outcomes after adrenalectomy in patients with primary aldosteronism (PA) are variable. The aldosteronoma resolution score (ARS) uses preoperative variables to calculate a score that identifies those patients that are more likely to have resolution of hypertension after adrenalectomy. We aim to determine the efficacy of adrenalectomy and whether the ARS accurately predicts clinical success in a Black and Hispanic population., Methods: We reviewed patients who underwent adrenalectomy for PA from 2004 to 2018 at two academic centers treating primarily Hispanic and Black patients. Postoperative outcomes were evaluated based on the primary aldosteronism surgical outcome consensus criterion. Retrospectively, the accuracy of ARS was determined by a receiver operating characteristic curve and the area under the curve (AUC)., Results: Forty-three Hispanic and 10 Black patients underwent adrenalectomy for PA. Twenty-two patients (41.5%) had complete clinical success. Variables associated with complete clinical success in the univariate analysis were female gender (p = 0.026), younger age (p = 0.001), lower preoperative aldosterone (p = 0.035), lower preoperative systolic blood pressure (p = 0.001), fewer number of preoperative antihypertensive medications (p = 0.007) and a higher ARS (p = 0.003). On multivariate analysis, only fewer number of preoperative antihypertensive medications was independently associated with complete clinical success (p = 0.026). The AUC of the ARS was 0.746., Conclusion: The rate of clinical success from adrenalectomy is good for Hispanic and Black patients with PA. Our analysis shows that the ARS is an accurate test of clinical success in Hispanic and Black patients. The ARS may be utilized preoperatively to frame expectations after adrenalectomy in these populations.
- Published
- 2021
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17. Pancreatic Cancer Surgery Following Emergency Department Admission: Understanding Poor Outcomes and Disparities in Care.
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Mehta VV, Friedmann P, McAuliffe JC, Muscarella P 2nd, and In H
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- Emergency Service, Hospital, Hospitalization, Humans, Retrospective Studies, United States epidemiology, Pancreatectomy, Pancreatic Neoplasms surgery
- Abstract
Background: The impact of emergency department admission prior to pancreatic resection on perioperative outcomes is not well described. We compared patients who underwent pancreatic cancer surgery following admission through the emergency department (ED-surgery) with patients receiving elective pancreatic cancer surgery (elective) and outcomes., Study Design: The Nationwide Inpatient Sample database was used to identify patients undergoing pancreatectomy for cancer over 5 years (2008-2012). Demographics and hospital characteristics were assessed, along with perioperative outcomes and disposition status., Results: A total of 8158 patients were identified, of which 516 (6.3%) underwent surgery after admission through the ED. ED-surgery patients were more often socioeconomically disadvantaged (non-White 39% vs. 18%, Medicaid or uninsured 24% vs. 7%, from lowest income area 33% vs. 21%; all p < .0001), had higher comorbidity (Elixhauser score > 6: 44% vs. 26%, p < .0001), and often had pancreatectomy performed at sites with lower annual case volume (< 7 resections/year: 53% vs. 24%, p < .0001). ED-surgery patients were less likely to be discharged home after surgery (70% vs. 82%, p < .0001) and had higher mortality (7.4% vs. 3.5%, p < .0001). On multivariate analysis, ED-surgery was independently associated with a lower likelihood of being discharged home (aOR 0.55 (95%CI 0.43-0.70))., Conclusion: Patients undergoing pancreatectomy following ED admission experience worse outcomes compared with those who undergo surgery after elective admission. The excess of socioeconomically disadvantaged patients in this group suggests factors other than clinical considerations alone drive this decision. This study demonstrates the need to consider presenting patient circumstances and preoperative oncologic coordination to reduce disparities and improve outcomes for pancreatic cancer surgery.
- Published
- 2021
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18. Clinical Stage of Cancer Affects Perioperative Mortality for Gastrointestinal Cancer Surgeries.
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Bliton J, Parides M, Muscarella P, McAuliffe JC, Papalezova K, and In H
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- Adult, Age Factors, Aged, Aged, 80 and over, Carcinoma mortality, Clinical Decision Rules, Databases, Factual, Digestive System Neoplasms mortality, Female, Humans, Linear Models, Male, Middle Aged, Neoplasm Staging, Prognosis, Carcinoma pathology, Carcinoma surgery, Digestive System Neoplasms pathology, Digestive System Neoplasms surgery, Digestive System Surgical Procedures mortality
- Abstract
Background: The impact of the stage of cancer on perioperative mortality remains obscure. The purpose of this study was to investigate whether cancer stage influences 30-d mortality for gastric, pancreatic, and colorectal cancers., Methods: Data were collected from the National Cancer Database for patients undergoing resections for cancers of the stomach, pancreas, colon, or rectum between 2004 and 2015. The main analysis was conducted among patients with cancer stages 1-3. A sensitivity analysis also included cancer stage 4. Descriptive statistics were used to compare the patients' baseline characteristics. Generalized linear mixed models were used to evaluate the relationship between stage and 30-d mortality, controlling for other disease-, patient- and hospital-level factors. Pseudo R2 statistics (%Δ pseudo R
2 ) were used to quantify the relative explanatory capacity of the variables to the model for 30-d mortality. All analyses were performed using SAS 9.4., Results: The cohort included 24,468, 28,078, 176,285, and 64,947 patients with stomach, pancreas, colon, and rectal cancers, respectively. After adjusting for other variables, 30-d mortality was different by stage for all cancer types examined. The factor most strongly associated with 30-d mortality was age (%Δ pseudo R2 range 14%-39%). The prognostic impact of cancer stage (Stages 1, 2, or 3) on 30-d mortality was comparable to that of the Charlson comorbidity index., Conclusions: Cancer stage contributes to explaining differences observed in short-term mortality for gastrointestinal cancers. Short-term mortality models would benefit by including more granular cancer stage, beyond disseminated status alone., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2021
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19. Differences in Liver Parenchyma are Measurable with CT Radiomics at Initial Colon Resection in Patients that Develop Hepatic Metastases from Stage II/III Colon Cancer.
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Creasy JM, Cunanan KM, Chakraborty J, McAuliffe JC, Chou J, Gonen M, Kingham VS, Weiser MR, Balachandran VP, Drebin JA, Kingham TP, Jarnagin WR, D'Angelica MI, Do RKG, and Simpson AL
- Subjects
- Case-Control Studies, Humans, Neoplasm Recurrence, Local diagnostic imaging, Retrospective Studies, Tomography, X-Ray Computed, Colonic Neoplasms diagnostic imaging, Colonic Neoplasms surgery, Liver Neoplasms diagnostic imaging, Liver Neoplasms surgery
- Abstract
Background: Currently, there are no methods to identify patients with an increased risk of liver metastases to guide patient selection for liver-directed therapies. We tried to determine whether quantitative image features (radiomics) of the liver obtained from preoperative staging CT scans at the time of initial colon resection differ in patients that subsequently develop liver metastases, extrahepatic metastases, or demonstrate prolonged disease-free survival., Methods: Patients who underwent resection of stage II/III colon cancer from 2004 to 2012 with available preoperative CT scans were included in this single-institution, retrospective case-control study. Patients were grouped by initial recurrence patterns: liver recurrence, extrahepatic recurrence, or no evidence of disease at 5 years. Radiomic features of the liver parenchyma extracted from CT images were compared across groups., Results: The cohort consisted of 120 patients divided evenly between three recurrence groups, with an equal number of stage II and III patients in each group. After adjusting for multiple comparisons, 44 of 254 (17%) imaging features displayed different distributions across the three patient groups (p < 0.05), with the clearest distinction between those with liver recurrence and no evidence of disease. Increased heterogeneity in the liver parenchyma by radiomic analysis was protective of liver metastases., Conclusions: CT radiomics is a promising tool to identify patients at high risk of developing liver metastases and is worthy of further investigation and validation.
- Published
- 2021
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20. Neuroendocrine Tumor of the Common Bile Duct Associated With von Hippel-Lindau Disease.
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Romero-Velez G, Pereira X, Yang J, Panarelli NC, and McAuliffe JC
- Abstract
We report a case of a common bile duct neuroendocrine tumor discovered in a patient with von Hippel-Lindau disease to emphasize the importance of recognizing this unusual diagnosis. This case illustrates the importance of endoscopic evaluation and the potential diagnostic pitfalls which may impact its appropriate management: the anatomic proximity of more common von Hippel-Lindau disease-related tumors, pathologic evaluation, and staging. Therefore, awareness of this rare diagnosis is important for appropriate treatment., (© 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)
- Published
- 2021
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21. Evaluation of Adrenal Vein Sampling Use and Outcomes in Patients With Primary Aldosteronism.
- Author
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Yeung A, Friedmann P, In H, Bloomgarden N, McAuliffe JC, Libutti SK, and Laird AM
- Subjects
- Adrenal Cortex Function Tests standards, Adrenal Cortex Function Tests statistics & numerical data, Adrenal Glands blood supply, Adrenal Glands diagnostic imaging, Adrenal Glands metabolism, Adrenalectomy methods, Adult, Aged, Aged, 80 and over, Aldosterone blood, Blood Specimen Collection methods, Blood Specimen Collection standards, Blood Specimen Collection statistics & numerical data, Female, Follow-Up Studies, Guideline Adherence statistics & numerical data, Humans, Hyperaldosteronism blood, Hyperaldosteronism complications, Hyperaldosteronism therapy, Hypertension diagnosis, Hypertension etiology, Hypertension prevention & control, Laparoscopy statistics & numerical data, Male, Middle Aged, Patient Selection, Practice Guidelines as Topic, Renin blood, Retrospective Studies, Tomography, X-Ray Computed, Treatment Outcome, Unnecessary Procedures statistics & numerical data, Veins surgery, Young Adult, Adrenal Cortex Function Tests methods, Adrenalectomy statistics & numerical data, Clinical Decision-Making methods, Hyperaldosteronism diagnosis, Hypertension epidemiology
- Abstract
Background: Primary aldosteronism (PA) occurs in 10%-20% of patients with resistant hypertension. Guidelines recommend adrenal vein sampling (AVS) to identify patients for surgical management. We evaluate the use of AVS in managing PA to better understand the selection and outcomes of medical versus surgical treatment., Methods: A retrospective review was performed, and patients were divided into those who did (AVS) and did not have AVS (non-AVS). Demographics, aldosterone and renin levels, blood pressure, comorbidities, and antihypertensive medications were recorded. Reasons to defer AVS and medical versus surgical decision-making were examined and groups were compared., Results: We included 113 patients; 39.8% (45/113) had AVS, whereas 60.2% (68/113) did not. Groups were similar in age, body mass index, and initial systolic blood pressure (SBP). In patients who underwent AVS, 31 of 45 (68.9%) had unilateral secretion and were referred for surgery, whereas 13 of 45 (28.9%) had bilateral secretion. Of the 31 referred for surgery, 26 underwent laparoscopic adrenalectomy, all cured; four refused surgery; and one counseled toward medical management by their physician. In 68 non-AVS patients, 6 (8.8%) underwent adrenalectomy without sampling and 2 with no clinical improvement. The remaining deferrals were because of normal or bilateral adrenal nodules on imaging (8/68, 11.8%); medical management due to poor surgical candidacy (12/68, 17.6%); patient refusal of intervention (13/68, 19.1%); or reasons not stated (28/68, 41.1%). At the follow-up, patients who underwent AVS had lower median SBP (135.4 mmHg versus 144.7 mmHg, P = 0.0241) and shorter follow-up (17.7 mo versus 54.0 mo, P < 0.0001). Surgically managed patients had biochemical resolution of PA with normalization of potassium levels (3.6 to 4.7mEq/L, P < 0.00001)., Conclusions: AVS correctly selects patients for surgical management avoiding unnecessary surgery. However, despite guidelines, AVS is not always pursued as part of PA treatment, potentially excluding surgical candidates., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
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22. Coaltered Ras/B-raf and TP53 Is Associated with Extremes of Survivorship and Distinct Patterns of Metastasis in Patients with Metastatic Colorectal Cancer.
- Author
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Datta J, Smith JJ, Chatila WK, McAuliffe JC, Kandoth C, Vakiani E, Frankel TL, Ganesh K, Wasserman I, Lipsyc-Sharf M, Guillem J, Nash GM, Paty PB, Weiser MR, Saltz LB, Berger MF, Jarnagin WR, Balachandran V, Kingham TP, Kemeny NE, Cercek A, Garcia-Aguilar J, Taylor BS, Viale A, Yaeger R, Solit DB, Schultz N, and D'Angelica MI
- Subjects
- Cohort Studies, Colorectal Neoplasms classification, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Female, Follow-Up Studies, High-Throughput Nucleotide Sequencing methods, Humans, Male, Middle Aged, Neoplasm Metastasis, Prognosis, Survival Rate, Biomarkers, Tumor genetics, Colorectal Neoplasms mortality, GTP Phosphohydrolases genetics, Membrane Proteins genetics, Mutation, Proto-Oncogene Proteins B-raf genetics, Proto-Oncogene Proteins p21(ras) genetics, Tumor Suppressor Protein p53 genetics
- Abstract
Purpose: We aimed to investigate genomic correlates underlying extremes of survivorship in metastatic colorectal cancer and their applicability in informing survival in distinct subsets of patients with metastatic colorectal cancer., Experimental Design: We examined differences in oncogenic somatic alterations between metastatic colorectal cancer cohorts demonstrating extremes of survivorship following complete metastasectomy: ≤2-year ( n = 17) and ≥10-year ( n = 18) survivors. Relevant genomic findings, and their association with overall survival (OS), were validated in two independent datasets of 935 stage IV and 443 resected stage I-IV patients., Results: In the extremes-of-survivorship cohort, significant co-occurrence of KRAS hotspot mutations and TP53 alterations was observed in ≤2-year survivors ( P < 0.001). When validating these findings in the independent cohort of 935 stage IV patients, incorporation of the cumulative effect of any oncogenic Ras/B-raf (i.e., either KRAS, NRAS , or BRAF ) and TP53 alteration generated three prognostic clusters: (i) TP53 -altered alone (median OS, 132 months); (ii) Ras/B-raf -altered alone (65 months) or Ras/B-raf - and TP53 pan-wild-type (60 months); and (iii) coaltered Ras/B-raf - TP53 (40 months; P < 0.0001). Coaltered Ras/B-raf - TP53 was independently associated with mortality (HR, 2.47; 95% confidence interval, 1.91-3.21; P < 0.001). This molecular profile predicted survival in the second independent cohort of 443 resected stage I-IV patients. Coaltered Ras/B-raf - TP53 was associated with worse OS in patients with liver ( n = 490) and lung ( n = 172) but not peritoneal surface ( n = 149) metastases. Moreover, coaltered Ras/B-raf - TP53 tumors were significantly more likely to involve extrahepatic metastatic sites with limited salvage options., Conclusions: Genomic analysis of extremes of survivorship following colorectal cancer metastasectomy identifies a prognostic role for coaltered Ras/B-raf - TP53 and its association with distinct patterns of colorectal cancer metastasis., (©2019 American Association for Cancer Research.)
- Published
- 2020
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23. Feasibility and efficacy of gamification in general surgery residency: Preliminary outcomes of residency teams.
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McAuliffe JC, McAuliffe RH Jr, Romero-Velez G, Statter M, Melvin WS, and Muscarella P 2nd
- Subjects
- Academic Medical Centers, Adult, Attitude of Health Personnel, Curriculum, Educational Measurement, Feasibility Studies, Female, Humans, Internship and Residency organization & administration, Male, New York City, Surveys and Questionnaires, Clinical Competence, Education, Medical, Graduate organization & administration, General Surgery education, Patient Care Team organization & administration, Personal Satisfaction
- Abstract
Background: Comprehensive studies evaluating the efficacy of team-based competition ("Gamification") in surgery have not been performed. Board pass rates and resident satisfaction may improve if surgical residents are involved in competition., Methods: Residents at Montefiore Medical Center (Bronx, New York) were surveyed and separated into teams during a draft. Each resident's performance was converted into a point system. Resident scores were combined into a team score and presented as a leaderboard. Awards were given. ABSITE, ACGME residency satisfaction, and ABS qualifying exam pass rates were compared., Results: Sixty percent of residents are inspired to improve their performance during gamification. ABSITE average percentile score improved from 28 to 43. ABS qualifying exam pass rates improved from 73% to 100%. Resident satisfaction improved from 65% to 88%. The point system allowed for establishing "growth curves" for each resident enabling enhanced assessment of residents., Conclusions: A comprehensive team-based competition inspires performance, is feasible, and seems to improve ABSITE scores, ABS pass rates, and satisfaction while being a tool for assessment of performance., Competing Interests: Declaration of competing interest The authors report no proprietary or commercial interest in any product mentioned or concept discussed in this article. All authors have confirmed their participation in this study and approve of its submission for publication., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2020
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24. Perioperative Mortality Does Not Explain Racial Disparities in Gastrointestinal Cancer.
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Bliton J, Muscarella P, Friedmann P, Parides M, Papalezova K, McAuliffe JC, and In H
- Subjects
- Aged, Female, Gastrointestinal Neoplasms surgery, Humans, Income, Male, Middle Aged, Perioperative Period, Socioeconomic Factors, Survival Rate trends, United States epidemiology, Digestive System Surgical Procedures methods, Gastrointestinal Neoplasms ethnology, Healthcare Disparities ethnology, Racial Groups
- Abstract
Background: Racial minorities with gastrointestinal cancer suffer disproportionately poor overall and disease-specific survival. We used a nationally representative sample to examine the relationship between race/ethnicity and mortality and determine whether these disparities were observed in the perioperative period., Materials and Methods: The Nationwide Inpatient Sample (NIS) was used to examine patients undergoing surgery for cancers of the esophagus, stomach, pancreas, colon and rectum ("GI cancer") between 2008 and 2012. Logistic regression was used to evaluate whether race/ethnicity was associated with perioperative mortality after adjusting for sociodemographic characteristics, perioperative factors and presentation (ER vs elective)., Results: A total of 110,044 subjects were identified, including 75.8% Whites, 10.5% Black patients, 7.2% Hispanic patients, and 3.1% Asian/Pacific Islanders (API). Whites were generally older than minorities. In adjusted multivariable generalized linear mixed logistic models, no increase in perioperative mortality was seen for minorities. Worse outcomes were observed for those with higher Elixhauser comorbidity score (OR 6.90, CI 5.96-7.99), lower income region (OR 1.24, CI 1.10-1.40), males (OR 1.54, CI 1.42-1.68), and those without private insurance (Medicare OR 1.34, CI 1.16-1.55; Medicaid OR 1.27, CI 1.02-1.58; self-pay OR 1.64, CI 1.24-2.17). Differences in mortality were predominantly driven by comorbidities (pseudo %ΔR
2 = 38.56%) and only minimally by race (pseudo %ΔR2 = 0.49%)., Conclusion: Minority groups do not suffer higher rates of perioperative mortality for GI cancer surgeries after controlling for clinical and demographic factors. Future work to address cancer disparities should focus on areas in the cancer care trajectory such as cancer screening, surveillance, socioeconomic factors, and access.- Published
- 2019
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25. Prevalence of False-Negative Results of Intraoperative Consultation on Surgical Margins During Resection of Gastric and Gastroesophageal Adenocarcinoma.
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McAuliffe JC, Tang LH, Kamrani K, Olino K, Klimstra DS, Brennan MF, and Coit DG
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- Adolescent, Adult, Aged, Aged, 80 and over, False Negative Reactions, Female, Humans, Intraoperative Care methods, Male, Margins of Excision, Middle Aged, Retrospective Studies, Treatment Outcome, Young Adult, Adenocarcinoma surgery, Esophageal Neoplasms surgery, Esophagogastric Junction surgery, Stomach Neoplasms surgery
- Abstract
Importance: Intraoperative consultation (IOC) on surgical margins during curative intent resection of gastric and gastroesophageal adenocarcinoma presents sampling and interpretive challenges. A false-negative (FN) IOC result can affect clinical care. Many factors may be associated with higher risk for an FN result of IOC on surgical margins., Objective: To assess the prevalence and clinical implications of FN results of IOC on surgical margins during resection of gastric and gastroesophageal adenocarcinoma., Design, Setting, and Participants: This retrospective study assessed the results of IOC on surgical margins to determine the prevalence of FN results and the accuracy and clinical implications of the results for patients undergoing curative intent resection for gastric or gastroesophageal adenocarcinoma. The study examined patients with gastric or gastroesophageal adenocarcinoma who underwent resection with curative intent at a single-institution referral center from January 1, 1992, to December 31, 2015., Interventions: Curative intent gastric and/or esophageal resection., Main Outcomes and Measures: False-negative results of IOC on surgical margins, accuracy of the results, factors associated with decreased accuracy of the results, and clinical implications of FN results., Results: This study included 2002 patients (median age, 65 years; 1343 [67.1%] male; 1638 [81.8%] white) who received 3171 IOCs on surgical margins. Of the 3171 IOCs, the prevalence of FN results was 1.7%, with an accuracy of 98.1%. The prevalence of an FN IOC result was 1.2% for esophageal margins, 2.0% for gastric margins, and 2.5% for duodenal margins (P = .04). The prevalence of an FN IOC result was higher for patients with diffuse or signet ring disease compared with those without (2.6% vs 1.2%, P = .002) and for those not receiving neoadjuvant radiotherapy compared with those receiving neoadjuvant radiotherapy (1.4% vs 0.7%, P < .001). The prevalence of FN results of IOCs performed by nongastrointestinal pathologists was similar to that of IOCs performed by gastrointestinal pathologists (2.3% vs 1.9%, P = .60). The disease-specific survival was 34 months (95% CI, 20.7-47.2 months) for those with an FN result and 26.9 months (95% CI, 18.3-35.4; P = .72) for those with a true-positive result. Half of the patients with FN IOC results received further margin-directed therapy, including subsequent resection or radiotherapy., Conclusions and Relevance: This study found that IOC on surgical margins was accurate at a specialty center. Signet ring or diffuse disease, duodenal margins, and not receiving neoadjuvant radiotherapy were challenging scenarios for IOC on surgical margins. The use of IOC on surgical margins may be optimal when it will affect intraoperative decision making framed by the stage of disease, tumor location, and surgical fitness of the patient.
- Published
- 2019
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26. Randomized Controlled Trials in Neuroendocrine Tumors.
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McAuliffe JC and Wolin EM
- Subjects
- Humans, Neuroendocrine Tumors diagnosis, Neuroendocrine Tumors therapy, Randomized Controlled Trials as Topic
- Abstract
Understanding of neuroendocrine tumors has increased greatly in the last 2 decades. Along with this, the prevalence of neuroendocrine tumors has increased because of the ubiquitous use of cross-sectional imaging, improved endoscopic screening, and the indolent nature of the disease. Up to 35% of patients have symptoms at the time of diagnosis, whereas the others have occult disease. Neuroendocrine tumors are a diverse group of malignancies with unique clinical courses. This article critically reviews the most important randomized controlled trials for neuroendocrine tumors and introduces a few awaiting completion., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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27. "Adjuvant" Hyperthermic Intraperitoneal Chemotherapy: A Call to Action.
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McAuliffe JC and Nash GM
- Subjects
- Chemotherapy, Adjuvant, Colorectal Neoplasms pathology, Combined Modality Therapy, Humans, Peritoneal Neoplasms secondary, Prognosis, Chemotherapy, Cancer, Regional Perfusion, Colorectal Neoplasms therapy, Hyperthermia, Induced, Peritoneal Neoplasms therapy
- Published
- 2017
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28. Isolation of isoprene degrading bacteria from soils, development of isoA gene probes and identification of the active isoprene-degrading soil community using DNA-stable isotope probing.
- Author
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El Khawand M, Crombie AT, Johnston A, Vavlline DV, McAuliffe JC, Latone JA, Primak YA, Lee SK, Whited GM, McGenity TJ, and Murrell JC
- Subjects
- Atmosphere analysis, Bacteria genetics, Base Sequence, Climate Change, DNA metabolism, DNA Probes, DNA, Bacterial genetics, Genome, Bacterial genetics, Methane metabolism, Sequence Analysis, DNA, Soil, Soil Microbiology, Bacteria metabolism, Butadienes metabolism, Carbon Cycle physiology, Hemiterpenes metabolism, Oxygenases metabolism, Pentanes metabolism, Plants metabolism, Volatile Organic Compounds metabolism
- Abstract
Emissions of biogenic volatile organic compounds (bVOCs), are an important element in the global carbon cycle, accounting for a significant proportion of fixed carbon. They contribute directly and indirectly to global warming and climate change and have a major effect on atmospheric chemistry. Plants emit isoprene to the atmosphere in similar quantities to emissions of methane from all sources and each accounts for approximately one third of total VOCs. Although methanotrophs, capable of growth on methane, have been intensively studied, we know little of isoprene biodegradation. Here, we report the isolation of two isoprene-degrading strains from the terrestrial environment and describe the design and testing of polymerase chain reaction (PCR) primers targeting isoA, the gene encoding the active-site component of the conserved isoprene monooxygenase, which are capable of retrieving isoA sequences from isoprene-enriched environmental samples. Stable isotope probing experiments, using biosynthesized (13) C-labelled isoprene, identified the active isoprene-degrading bacteria in soil. This study identifies novel isoprene-degrading strains using both culture-dependent and, for the first time, culture-independent methods and provides the tools and foundations for continued investigation of the biogeography and molecular ecology of isoprene-degrading bacteria., (© 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.)
- Published
- 2016
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29. Hepatic resection, hepatic arterial infusion pump therapy, and genetic biomarkers in the management of hepatic metastases from colorectal cancer.
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McAuliffe JC, Qadan M, and D'Angelica MI
- Abstract
The liver is the most common site of colorectal cancer metastasis. Fortunately, improvements have been made in the care of patients with colorectal liver metastasis (CRLM). Effective management of CRLM requires a multidisciplinary approach that is tailored to individuals in order to achieve long-term survival, and cure. Resection and systemic chemotherapy provides benefit in selected individuals. An adjunct to resection and/or systemic chemotherapy is the use of hepatic arterial infusion pump (HAIP) therapy. Many studies show HAIP provides benefit for select patients with CRLM. Added to the crucible of a multidisciplinary approach to managing CRLM is the ever growing understanding of tumor biology and genetic profiling. In this review, we discuss the outcomes of resection, systemic therapies and HAIP therapy for CRLM. We also discuss the impact of recent advances in genetic profiling and mutational analysis, namely mutation of KRAS and BRAF, for this disease.
- Published
- 2015
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30. Computed tomography attenuation and patient characteristics as predictors of complications after pancreaticoduodenectomy.
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McAuliffe JC, Parks K, Kumar P, McNeal SF, Morgan DE, and Christein JD
- Subjects
- Aged, Body Mass Index, Chi-Square Distribution, Female, Humans, Logistic Models, Male, Middle Aged, Multivariate Analysis, Obesity diagnosis, Obesity mortality, Pancreatic Fistula mortality, Pancreatic Fistula therapy, Pancreaticoduodenectomy mortality, Predictive Value of Tests, Risk Factors, Time Factors, Treatment Outcome, Intra-Abdominal Fat diagnostic imaging, Obesity complications, Pancreatic Fistula etiology, Pancreaticoduodenectomy adverse effects, Tomography, X-Ray Computed, Viscera diagnostic imaging
- Abstract
Objectives: Morbidity after pancreaticoduodenectomy (PD) remains high. Computed tomography (CT) of intra-abdominal tissue has not been thoroughly evaluated to establish associations with the occurrence of complications after PD. The current study sought to determine whether differences in non-enhanced visceral attenuation predicted complications after PD., Methods: Outcomes in patients undergoing PD were analysed according to the Clavien system for classifying complications and the International Study Group on Pancreatic Fistula system for classifying postoperative pancreatic fistula (POPF). Preoperative non-enhanced CT scans were evaluated by a blinded investigator for attenuation of abdominal viscera and fat thickness. Data on pancreatic firmness and pancreatic duct size were collected. Univariate and multivariate analyses were performed., Results: A total of 134 patients underwent PD for malignant and benign disease. Rates of morbidity, mortality and POPF at 90 days were 61%, 4% and 23%, respectively. Patients with a body mass index of > 25 kg/m(2) had higher rates of POPF (P = 0.05) and complications (P < 0.01). In multivariate analysis, patients were more likely to develop any complication as CT attenuation decreased for paraspinus muscle (P < 0.01), spleen (P < 0.03) and liver (P = 0.01) parenchyma., Conclusions: Postoperative complications after PD remain prevalent. Decreased CT attenuation of abdominal viscera is an independent predictor of morbidity after PD and suggests a high-risk patient physiology for pancreatic resection., (© 2013 International Hepato-Pancreato-Biliary Association.)
- Published
- 2013
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31. Type 2 diabetes mellitus and pancreatic cancer.
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McAuliffe JC and Christein JD
- Subjects
- Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 physiopathology, Humans, Pancreatectomy, Pancreatic Neoplasms diagnosis, Pancreatic Neoplasms physiopathology, Pancreatic Neoplasms surgery, Risk Factors, Diabetes Mellitus, Type 2 complications, Pancreatic Neoplasms complications
- Abstract
Tumorigenesis of pancreatic cancer (PC) and the pathophysiology of type 2 diabetes mellitus (DM2) are emerging as intertwined pathways. As the operative morbidity and mortality of pancreatectomy has improved, incidence has increased and survival has remained mostly unchanged. The diagnosis of DM2 suggests pancreatic dysfunction and possible early carcinogenesis. DM2 is a significant comorbidity predicting worse outcomes in patients undergoing pancreatic resection as part of the treatment of PC. This article examines this phenomena and suggests possible approaches to screening and diagnosis., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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32. Should pancreatectomy with islet cell autotransplantation in patients with chronic alcoholic pancreatitis be abandoned?
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Dunderdale J, McAuliffe JC, McNeal SF, Bryant SM, Yancey BD, Flowers G, and Christein JD
- Subjects
- Adult, Chronic Disease, Female, Humans, Male, Middle Aged, Retrospective Studies, Islets of Langerhans Transplantation, Pancreatectomy methods, Pancreatitis, Alcoholic surgery, Patient Selection
- Abstract
Background: Pancreatectomy or drainage has been advocated for pain due to chronic pancreatitis. Islet cell autotransplantation (IAT) may improve quality of life (QOL); optimal patient selection has not been established., Study Design: Outcomes of 100 patients who underwent pancreatectomy with islet isolation between 2005 and 2012 were assessed by etiology (alcoholic pancreatitis [AP] 30%, and nonalcoholic pancreatitis [NAP] 70%). Insulin requirement, Short Form-36, and McGill Pain Questionnaires were assessed. Data were analyzed using SASv9.2., Results: Of the 100 patients, isolation was unsuccessful in 9 patients due to fibrosis. Alcoholic pancreatitis was associated with 7 of 9 failed isolations (23% vs 3%, p < 0.01), and all of these patients are now diabetic. Ninety-one patients (age 44 years, follow-up 19 months, 23% AP) underwent resection with IAT. Total islet yield (islet cell equivalents [IEQ]) and IEQ/kg body weight were less for patients with AP (81,000 vs 150,000, p < 0.01; 1,260 vs 2,190, respectively, p = 0.01) overall and more specifically, for total pancreatectomy (92,000 vs 188,000, respectively, p = 0.02). Twenty-eight (34%) of all patients who had resections and 15% of those undergoing total pancreatectomy are insulin free. Multivariate analysis identified AP as an independent predictor of insulin units/day (p = 0.01). Complete pre- and postoperative QOL and pain surveys were available on 69 patients. Patients with AP had less QOL improvement (1 of 8 vs 5 of 8 domains, p < 0.01) and "present pain" improvement at 2 years from preoperative levels in those with NAP; no improvement in QOL was seen in those with AP (NAP 2.7 to 1.2, p < 0.01; AP 2.7 to 2.2, p > 0.05)., Conclusions: After pancreatic resection with planned IAT, AP resulted in failed isolations, lower yields, higher insulin requirements, poor long-term QOL improvement, and no improvement in pain scores compared with NAP. Further studies should define criteria for resection and IAT for patients with alcoholic chronic pancreatitis., (Copyright © 2013 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
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33. Autophagy inhibition and antimalarials promote cell death in gastrointestinal stromal tumor (GIST).
- Author
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Gupta A, Roy S, Lazar AJ, Wang WL, McAuliffe JC, Reynoso D, McMahon J, Taguchi T, Floris G, Debiec-Rychter M, Schoffski P, Trent JA, Debnath J, and Rubin BP
- Subjects
- Benzamides, Cell Death drug effects, Cell Survival drug effects, Drug Resistance, Neoplasm drug effects, Drug Therapy, Combination, Gastrointestinal Stromal Tumors pathology, Humans, Imatinib Mesylate, Piperazines pharmacology, Pyrimidines pharmacology, Antimalarials pharmacology, Autophagy drug effects, Gastrointestinal Stromal Tumors drug therapy
- Abstract
Although gastrointestinal stromal tumors (GISTs) harboring activating KIT or platelet-derived growth factor receptor A (PDGFRA) mutations respond to treatment with targeted KIT/PDGFRA inhibitors such as imatinib mesylate, these treatments are rarely curative. Most often, a sizeable tumor cell subpopulation survives and remains quiescent for years, eventually resulting in acquired resistance and treatment failure. Here, we report that imatinib induces autophagy as a survival pathway in quiescent GIST cells. Inhibiting autophagy, using RNAi-mediated silencing of autophagy regulators (ATGs) or antimalarial lysosomotrophic agents, promotes the death of GIST cells both in vitro and in vivo. Thus, combining imatinib with autophagy inhibition represents a potentially valuable strategy to promote GIST cytotoxicity and to diminish both cellular quiescence and acquired resistance in GIST patients.
- Published
- 2010
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34. A randomized, phase II study of preoperative plus postoperative imatinib in GIST: evidence of rapid radiographic response and temporal induction of tumor cell apoptosis.
- Author
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McAuliffe JC, Hunt KK, Lazar AJ, Choi H, Qiao W, Thall P, Pollock RE, Benjamin RS, and Trent JC
- Subjects
- Benzamides, Combined Modality Therapy, Female, Gastrointestinal Stromal Tumors diagnostic imaging, Gastrointestinal Stromal Tumors surgery, Humans, Imatinib Mesylate, Male, Middle Aged, Radiography, Remission Induction, Antineoplastic Agents administration & dosage, Apoptosis drug effects, Gastrointestinal Stromal Tumors drug therapy, Piperazines administration & dosage, Pyrimidines administration & dosage
- Abstract
Gastrointestinal stromal tumor (GIST) is the most common sarcoma arising in the gastrointestinal (GI) tract. Imatinib mesylate (imatinib) is efficacious in treating advanced and metastatic GIST. Patients undergoing resection of GIST realize a highly variable median disease-free survival (DFS). In the absence of prospective data, we conducted a randomized, phase II study to assess the safety and efficacy of preoperative and postoperative imatinib for the treatment of GIST. Nineteen GIST patients undergoing surgical resection were randomized to receive 3, 5, or 7 days of preoperative imatinib (600 mg daily). Patients received postoperative imatinib for 2 years. Perioperative adverse events were compared with those in an imatinib-naïve historical control. The efficacy of imatinib was assessed by (18)fluorodeoxyglucose positron emission tomography ((18)FDG-PET), dynamic computed tomography (dCT), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and DFS. Imatinib did not affect surgical morbidity as compared with an imatinib-naïve cohort (p >/= 0.1). Most patients responded to preoperative imatinib by (18)FDG-PET and dCT (69% and 71%, respectively). Tumor cell apoptosis increased by an average of 12% (range 0-33%) and correlated with the duration of preoperative imatinib (p = 0.04). Median DFS of patients treated with surgery and imatinib was 46 months (range 10-46 months). Tumor size was a predictor of recurrence after postoperative imatinib (p = 0.02). Imatinib appears to be safe and may be considered for patients undergoing surgical resection of their GIST. Radiographic response and tumor cell apoptosis occur within the first week of imatinib therapy.
- Published
- 2009
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35. Unlucky number 13? Differential effects of KIT exon 13 mutation in gastrointestinal stromal tumors.
- Author
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McAuliffe JC, Wang WL, Pavan GM, Pricl S, Yang D, Chen SS, Lazar AJ, Pollock RE, and Trent JC
- Subjects
- Benzamides, Drug Resistance, Neoplasm genetics, Exons, Gastrointestinal Stromal Tumors drug therapy, Humans, Imatinib Mesylate, Male, Piperazines therapeutic use, Pyrimidines therapeutic use, Gastrointestinal Stromal Tumors genetics, Mutation, Missense, Proto-Oncogene Proteins c-kit genetics
- Published
- 2008
- Full Text
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36. Clinical, histopathologic, molecular and therapeutic findings in a large kindred with gastrointestinal stromal tumor.
- Author
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Kleinbaum EP, Lazar AJ, Tamborini E, Mcauliffe JC, Sylvestre PB, Sunnenberg TD, Strong L, Chen LL, Choi H, Benjamin RS, Zhang W, and Trent JC
- Subjects
- Adult, Aged, Benzamides, Female, Gastrointestinal Stromal Tumors metabolism, Humans, Imatinib Mesylate, In Situ Hybridization, Fluorescence, Male, Middle Aged, Protein-Tyrosine Kinases antagonists & inhibitors, Proto-Oncogene Proteins c-kit genetics, Receptor, Platelet-Derived Growth Factor alpha genetics, Antineoplastic Agents therapeutic use, Gastrointestinal Stromal Tumors drug therapy, Gastrointestinal Stromal Tumors pathology, Piperazines therapeutic use, Proto-Oncogene Proteins c-kit metabolism, Pyrimidines therapeutic use, Receptor, Platelet-Derived Growth Factor alpha metabolism
- Abstract
Germ-line mutations in the KIT receptor tyrosine kinase gene have been described in families with a propensity to develop gastrointestinal stromal tumor (GIST). There is limited information from large kindreds regarding median age at diagnosis, detailed histopathology, clinical effects of imatinib therapy and chromosomal abnormalities of the KIT gene. We identified a large kindred with GIST. Each family member was interviewed and appropriate medical records and radiographic imaging were obtained. Archival tumor tissue was obtained to confirm diagnosis, extract genomic DNA and perform fluorescent in situ hybridization cytogenetics of the KIT gene. Fifteen of 79 individuals with GIST were identified in this kindred. There were 8 males, the mean age at diagnosis was 53.9 (range 45-71) years. Histopathology revealed microscopic proliferation and nodularity in the myenteric plexus, spindled morphology, diffuse Kit but variable CD34 staining and low mitotic rates in the setting of metastatic disease. A deletion of codon 579 in exon 11 of the KIT gene was identified in tumor and normal tissue of this family. Mutation and cytogenetic analysis revealed homozygous loss of the wild-type KIT sequence in tumor from one individual. Four of 4 individuals treated with imatinib are alive and without progression while 9 of 11 individuals not treated with imatinib are deceased. This study describes a kindred with a propensity to develop GIST in an autosomal dominant pattern. Germ-line deletion of KIT codon 579 in GIST is associated with clinical benefit from imatinib, limited utility of mitoses to predict malignant potential, and a novel homozygous deletion of this codon in one individual., ((c) 2007 Wiley-Liss, Inc.)
- Published
- 2008
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37. Association of intratumoral vascular endothelial growth factor expression and clinical outcome for patients with gastrointestinal stromal tumors treated with imatinib mesylate.
- Author
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McAuliffe JC, Lazar AJ, Yang D, Steinert DM, Qiao W, Thall PF, Raymond AK, Benjamin RS, and Trent JC
- Subjects
- Adult, Aged, Aged, 80 and over, Benzamides, Cohort Studies, Female, Humans, Imatinib Mesylate, Male, Middle Aged, Prognosis, Tissue Array Analysis, Treatment Outcome, Vascular Endothelial Growth Factor A analysis, Vascular Endothelial Growth Factor A genetics, Antineoplastic Agents therapeutic use, Gastrointestinal Stromal Tumors drug therapy, Piperazines therapeutic use, Protein Kinase Inhibitors therapeutic use, Pyrimidines therapeutic use, Vascular Endothelial Growth Factor A metabolism
- Abstract
Purpose: Imatinib mesylate (imatinib) has revolutionized clinical outcomes of patients with advanced gastrointestinal stromal tumor (GIST). However, the degree of individual benefit varies, and little is known about prognostic factors for these patients. Importantly, selected patients may be treated with an approach to target both Kit and vascular endothelial growth factor receptor (VEGFR) expression., Experimental Design: Using tissue microarray technology, we analyzed 53 imatinib-naive GISTs for vascular endothelial growth factor (VEGF) expression from patients who then received imatinib. In multivariate analyses, we evaluated overall survival (OS) and progression-free survival (PFS) of these patients based on putative prognostic factors, including VEGF expression. In a separate study, 12 matched pre-imatinib and post-imatinib GIST patient specimens and two human GIST cell lines were assessed for VEGF production in response to imatinib., Results: Independent of kit genotype, patients with GIST expressing high VEGF had inferior median PFS (7.1 months versus 29 months, P = 0.42) and median OS (20 months versus not reached at >50 months; P = 0.02) compared with weak or nonexpressers of VEGF. Non-exon 11 kit mutation predicted inferior PFS but not OS. High mitotic rate was marginally predictive of improved OS. Imatinib resulted in decreased production of VEGF in only a subset of GIST patients (2 of 12) and both cell lines., Conclusions: We present a study to address the prognostic factors for patients with GIST in the imatinib era. We present a rationale to consider exploration of a front-line therapy of GIST with a regimen targeting both Kit and VEGFR based on the presence of tumor VEGF levels.
- Published
- 2007
- Full Text
- View/download PDF
38. Biomarkers in gastrointestinal stromal tumor: should we equate blood-based pharmacodynamics with tumor biology and clinical outcomes?
- Author
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McAuliffe JC and Trent JC
- Subjects
- Antineoplastic Agents therapeutic use, Humans, Survival, Treatment Outcome, Antineoplastic Agents pharmacology, Biomarkers blood, Gastrointestinal Stromal Tumors drug therapy, Gastrointestinal Stromal Tumors mortality
- Published
- 2007
- Full Text
- View/download PDF
39. Update on the biology and therapy of gastrointestinal stromal tumors.
- Author
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D'Amato G, Steinert DM, McAuliffe JC, and Trent JC
- Subjects
- Antineoplastic Agents therapeutic use, Benzamides, Gastrointestinal Stromal Tumors diagnosis, Gastrointestinal Stromal Tumors genetics, Gastrointestinal Stromal Tumors metabolism, Humans, Imatinib Mesylate, Infusions, Parenteral, Liver Neoplasms secondary, Liver Neoplasms therapy, Mutation, Piperazines therapeutic use, Prognosis, Protein Kinase Inhibitors therapeutic use, Protein-Tyrosine Kinases metabolism, Proto-Oncogene Proteins c-kit genetics, Proto-Oncogene Proteins c-kit metabolism, Pyrimidines therapeutic use, Treatment Outcome, Gastrointestinal Stromal Tumors physiopathology, Gastrointestinal Stromal Tumors therapy
- Abstract
Background: Gastrointestinal stromal tumors (GISTs), the most common mesenchymal tumors of the gastrointestinal tract, are an example of a disease with an effective, molecularly targeted therapy., Methods: Published articles and author experience were used to comprehensively define the clinical features, biology, and state-of-the-art therapy of GISTs., Results: GISTs are thought to originate from the neoplastic transformation of the interstitial cells of Cajal, the intestinal pacemaker cells. GISTs commonly have mutations in the kit gene, resulting in a gain-of-function mutation and ligand-independent constitutive activation of the KIT receptor tyrosine kinase. Successful tyrosine kinase inhibitors target the aberrant pathways that are critical for tumor cell viability. The development of imatinib mesylate (formerly STI 571) in the treatment of metastatic GISTs represents a therapeutic breakthrough., Conclusions: Progress in the clinical diagnosis has led to an increased recognition of this disease as a distinct clinical entity. Treatment of metastatic GIST with imatinib has led to unprecedented improvements in progression-free and overall survival. The use of imatinib in the preoperative and postoperative treatment of GISTs is an area of intense investigation.
- Published
- 2005
- Full Text
- View/download PDF
40. Imatinib mesylate in the treatment of gastrointestinal stromal tumour.
- Author
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Steinert DM, McAuliffe JC, and Trent JC
- Subjects
- Benzamides, Clinical Trials as Topic statistics & numerical data, Drug Administration Schedule, Humans, Imatinib Mesylate, Piperazines pharmacokinetics, Protein Kinase Inhibitors administration & dosage, Protein Kinase Inhibitors pharmacokinetics, Pyrimidines pharmacokinetics, Gastrointestinal Stromal Tumors drug therapy, Gastrointestinal Stromal Tumors enzymology, Piperazines administration & dosage, Pyrimidines administration & dosage
- Abstract
Imatinib mesylate is a selective and potent small-molecule inhibitor of tyrosine kinases, including Kit, platelet-derived growth factor receptor, and the BCR-Abl fusion protein. Kit plays an important role in gastrointestinal stromal tumours (GISTs) and is one of the most exciting therapeutic targets discovered so far. Clinical trials have consistently shown the dramatic efficacy of imatinib mesylate in patients with GIST. This article will review the development and pharmacology of this small-molecule inhibitor and summarise the clinical trials of imatinib mesylate for the treatment of GIST. Although imatinib mesylate has significantly improved the outcomes of most patients with advanced GIST, unanswered questions remain: what is the role of imatinib mesylate in the pre- and postoperative settings? What is the mechanism of the antitumour activity of imatinib? How do you manage patients whose tumours are refractory to imatinib mesylate?
- Published
- 2005
- Full Text
- View/download PDF
41. Synthesis of O-glycolyl-linked neuraminic acids through a spirocyclic intermediate.
- Author
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McAuliffe JC, Rabuka D, and Hindsgaul O
- Subjects
- Animals, Carbohydrate Conformation, Dimerization, Disaccharides chemical synthesis, Ovum chemistry, Sea Urchins chemistry, Spiro Compounds chemistry, Neuraminic Acids chemical synthesis
- Abstract
[reaction: see text] The neuraminic acid derivative 5 is readily converted in several steps to the neuraminic acid dimer 12, linked through the hydroxyl of a 5-N-glycolyl group in an alpha-2,5 glycosidic linkage. The sequence is shown to proceed through a spirocyclic intermediate 9 by in situ NMR experiments. Similar derivatives of N-glycolylneuraminic acid (Neu5Gc), including polymers, have been identified from marine sources, including starfish and sea urchins, often as sulfated derivatives and are thought to mediate sperm-egg recognition.
- Published
- 2002
- Full Text
- View/download PDF
42. Synthesis of selectively radiolabeled hexasaccharides for the determination of enzymatic regioselectivity.
- Author
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McAuliffe JC, Ujita M, Fukuda M, and Hindsgaul O
- Subjects
- Binding Sites, Carbohydrate Conformation, Carbohydrate Sequence, Glycosylation, In Vitro Techniques, Molecular Sequence Data, N-Acetyllactosamine Synthase metabolism, Oligosaccharides chemistry, Oligosaccharides metabolism, Radioisotopes, Oligosaccharides chemical synthesis
- Abstract
Poly-N-acetyllactosamines provide backbone structures for functional modifications such as sialyl Lewis X. To understand how the biosynthesis of poly-N-acetyllactosamines is regulated, two branched oligosaccharides of the structure Galbeta1,4GlcNAcbeta1, 6(Galbeta1,4GlcNAcbeta1,2)-Manalpha1,6Manbeta-octyl 1 and 2 were synthesized in which one of the terminal galactose units was selectively radiolabeled. Hexasaccharides 1 and 2 were assembled from the chemically synthesized pentasaccharide precursors GlcNAcbeta1,6(Galbeta1,4GlcNAcbeta1,2)-Manalpha1,6Manbeta-octyl3 and Galbeta1,4GlcNAcbeta1,6(GlcNAcbeta1,2) - Manalpha1,6 Manbeta-octyl 4 respectively, through treatment with UDP-1-[3H]-Gal and beta1,4 galactosyltransferase. Compounds 1 and 2 were subsequently incubated with UDP-GlcNAc and the UDP-GlcNAc: Galbeta1-4Glc(NAc) beta1,3-N-acetylglucosaminyltransferase (i-GlcNAc transferase) resulting in a partial conversion to a mixture of heptasaccharides which were purified by HPLC. The branch selectivity of the addition of N-acetylglucosamine to compounds 1 and 2 was then characterized by endo-beta-galactosidase digestion of the heptasaccharides, followed by isolation of the resultant pentasaccharides on C18 reverse-phase silica cartridges. Comparison of the amount of radiolabel to a control reaction lacking endo-beta-galactosidase indicated the favored site of GlcNAc addition to be the lower beta1,2-branch over the beta1,6 branch by a 3 :1 ratio.
- Published
- 1999
- Full Text
- View/download PDF
43. Expedient synthesis of a series of N-acetyllactosamines.
- Author
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McAuliffe JC, Fukuda M, and Hindsgaul O
- Subjects
- Carbohydrate Sequence, Glycosyltransferases metabolism, Kinetics, Mannosides chemical synthesis, Molecular Sequence Data, Oligosaccharides metabolism, Substrate Specificity, Amino Sugars chemistry, Oligosaccharides chemical synthesis
- Abstract
A series of poly-N-acetyllactosamines representative of those found on complex N-glycans was synthesized for use in the kinetic characterization of recently cloned glycosyltransferases. The syntheses involved the iterative addition of a selectively protected N-acetyllactosaminyl donor to an octyl alpha-D-mannopyranosyl-1,6-beta-D-mannopyranoside acceptor, followed by deprotection. In addition, non-reducing galactosyl residues were removed with beta-galactosidase to furnish GlcNAc terminated compounds. In this manner tetra- to octasaccharides were efficiently produced.
- Published
- 1999
- Full Text
- View/download PDF
44. Identification of glutamic acid 105 at the active site of Bacillus amyloliquefaciens 1,3-1,4-beta-D-glucan 4-glucanohydrolase using epoxide-based inhibitors.
- Author
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Høj PB, Condron R, Traeger JC, McAuliffe JC, and Stone BA
- Subjects
- Amino Acid Sequence, Binding Sites, Chromatography, High Pressure Liquid, Glutamic Acid, Glycoside Hydrolases antagonists & inhibitors, Mass Spectrometry, Molecular Sequence Data, Peptide Fragments isolation & purification, Peptide Mapping, Sequence Homology, Amino Acid, Serine Endopeptidases, Bacillus enzymology, Epoxy Compounds pharmacology, Glutamates, Glycoside Hydrolases metabolism
- Abstract
Bacillus amyloliquefaciens 1,3-1,4-beta-D-glucan 4-glucanohydrolase (EC 3.2.1.73) was modified by the mechanism-based, affinity-labeling reagent [14C](3,4)-epoxybutyl beta-D-cellobioside. Following partial inactivation a completely inactivated enzyme preparation containing 1.1 mol of covalently bound inhibitor/mol of protein was obtained by chromatography on a cellulosic matrix. The inactivated enzyme was digested with endoproteinase Glu-C and radioactive peptides purified by reversed-phase high performance liquid chromatography (HPLC). The affinity label was esterified exclusively to the gamma-carboxylate of Glu105 in the sequence Gly-Thr-Pro-Trp-Asp-Glu-Ile-Asp-Ile-Glu109. The sequence motif Glu-(Ile/Leu)-Asp-Ile is found in many glucanases and xylanases and may therefore serve to identify the catalytic nucleophile in beta-glycanases, which otherwise exhibit a low degree of sequence identity. The esterification of Glu105 by the affinity label abolished endoproteinase Glu-C-mediated hydrolysis of the Glu-Ile106 peptide bond. Identification of phenylthiohydantoin-Glu105 during automated sequence analysis was not possible unless the affinity label was liberated by prior base hydrolysis. These observations formed the basis for the development of a highly sensitive approach for the identification of catalytic carboxylates in polysaccharide hydrolases employing non-radioactive inhibitors, comparative HPLC mapping, electrospray mass spectrometry, and Edman degradation.
- Published
- 1992
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