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Dive into the research topics where Alexandra G. Lopez-Aguiar is active.

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Featured researches published by Alexandra G. Lopez-Aguiar.


Journal of Surgical Oncology | 2018

Nomogram predicting the risk of recurrence after curative-intent resection of primary non-metastatic gastrointestinal neuroendocrine tumors: An analysis of the U.S. Neuroendocrine Tumor Study Group

Katiuscha Merath; Fabio Bagante; Eliza W. Beal; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola Smith; Cliff Cho; Megan Beems; Carl Schmidt; Mary Dillhoff; Shishir K. Maithel; Timothy M. Pawlik

The risk of recurrence after resection of non‐metastatic gastro‐entero‐pancreatic neuroendocrine tumors (GEP‐NET) is poorly defined. We developed/validated a nomogram to predict risk of recurrence after curative‐intent resection.


Surgery | 2018

Influence of carcinoid syndrome on the clinical characteristics and outcomes of patients with gastroenteropancreatic neuroendocrine tumors undergoing operative resection

Charles W. Kimbrough; Eliza W. Beal; Mary Dillhoff; Carl Schmidt; Timothy M. Pawlik; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Angelena Crown; Daniel E. Abbott; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola-Smith; Clifford S. Cho; Megan Beems; Shishir K. Maithel; Jordan M. Cloyd

Background: The incidence, clinical characteristics, and long‐term outcomes of patients with gastroenteropancreatic neuroendrocrine tumors and carcinoid syndrome undergoing operative resection have not been well characterized. Methods: Patients undergoing resection of primary or metastatic gastroenteropancreatic neuroendrocrine tumors between 2000 and 2016 were identified from an 8‐institution collaborative database. Clinicopathologic and postoperative characteristics as well as overall survival and disease‐free survival were compared among patients with and without carcinoid syndrome. Results: Among 2,182 patients who underwent resection, 139 (6.4%) had preoperative carcinoid syndrome. Patients with carcinoid syndrome were more likely to have midgut primary tumors (44.6% vs 21.4%, P < .001), lymph node metastasis (63.4% vs 44.3%, P < .001), and metastatic disease (62.8% vs 26.7%, P < .001). There was no difference in tumor differentiation, grade, or Ki67 status. Perioperative carcinoid crisis was rare (1.6% vs 0%, P < .01), and the presence of preoperative carcinoid syndrome was not associated with postoperative morbidity (38.8% vs 45.5%, P = .129). Substantial symptom improvement was reported in 59.5% of patients who underwent curative‐intent resection, but occurred in only 22.7% who underwent debulking. Despite an association on univariate analysis (P = .04), carcinoid syndrome was not independently associated with disease‐free survival after controlling for confounding factors (hazard ratio 0.97, 95% confidence interval 0.64–1.45). Preoperative carcinoid syndrome was not associated with overall survival on univariate or multivariate analysis. Conclusion: Among patients undergoing operative resection of gastroenteropancreatic neuroendrocrine tumors, the prevalence of preoperative carcinoid syndrome was low. Although operative intervention with resection or especially debulking in patients with carcinoid syndrome was disappointing and often failed to improve symptoms, after controlling for markers of tumor burden, carcinoid syndrome was not independently associated with worse disease‐free survival or overall survival.


Surgery | 2018

Margin status and long-term prognosis of primary pancreatic neuroendocrine tumor after curative resection: Results from the US Neuroendocrine Tumor Study Group

Xu-Feng Zhang; Zheng Wu; Jordan M. Cloyd; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola Smith; C.S. Cho; Megan Beems; Carl Schmidt; Mary Dillhoff; Shishir K. Maithel; Timothy M. Pawlik

Background: The impact of margin status on resection of primary pancreatic neuroendocrine tumors has been poorly defined. The objectives of the present study were to determine the impact of margin status on long‐term survival of patients with pancreatic neuroendocrine tumors after curative resection and evaluate the impact of reresection to obtain a microscopically negative margin. Methods: Patients who underwent curative‐intent resection for pancreatic neuroendocrine tumors between 2000 and 2016 were identified at 8 hepatobiliary centers. Overall and recurrence‐free survival were analyzed relative to surgical margin status using univariable and multivariable analyses. Results: Among 1,020 patients, 866 (84.9%) had an R0 (>1 mm margin) resection, whereas 154 (15.1%) had an R1 (≤1 mm margin) resection. R1 resection was associated with a worse recurrence‐free survival (10‐year recurrence‐free survival, R1 47.3% vs R0 62.8%, hazard ratio 1.8, 95% confidence interval 1.2–2.7, P = .002); residual tumor at either the transection margin (R1t) or the mobilization margin (R1m) was associated with increased recurrence versus R0 (R1t versus R0: hazard ratio 1.8, 95% confidence interval 1.0–3.0, P = .033; R1m versus R0: hazard ratio 1.3, 95% confidence interval 1.0–1.7, P = .060). In contrast, margin status was not associated with overall survival (10‐year overall survival, R1 71.1% vs R0 71.8%, P = .392). Intraoperatively, 539 (53.6%) patients had frozen section evaluation of the surgical margin; 49 (9.1%) patients had a positive margin on frozen section analysis; 38 of the 49 patients (77.6%) had reresection, and a final R0 (secondary R0) margin was achieved in 30 patients (78.9%). Extending resection to achieve an R0 status remained associated with worse overall survival (hazard ratio 3.1, 95% confidence interval 1.6–6.2, P = .001) and recurrence‐free survival (hazard ratio 2.6, 95% confidence interval 1.4–5.0, P = .004) compared with primary R0 resection. On multivariable analyses, tumor‐specific factors, such as cellular differentiation, perineural invasion, Ki‐67 index, and major vascular invasion, rather than surgical margin, were associated with long‐term outcomes. Conclusion: Margin status was not associated with long‐term survival. The reresection of an initially positive surgical margin to achieve a negative margin did not improve the outcome of patients with pancreatic neuroendocrine tumors. Parenchymal‐sparing pancreatic procedures for pancreatic neuroendocrine tumors may be appropriate when feasible.


Journal of Surgical Oncology | 2018

Association of perioperative transfusion with survival and recurrence after resection of gallbladder cancer: A 10-institution study from the US Extrahepatic Biliary Malignancy Consortium

Alexandra G. Lopez-Aguiar; Cecilia G. Ethun; Mia R. McInnis; Timothy M. Pawlik; George A. Poultsides; Thuy B. Tran; Kamran Idrees; Chelsea A. Isom; Ryan C. Fields; Bradley Krasnick; Sharon M. Weber; Ahmed Salem; Robert C.G. Martin; Charles R. Scoggins; Perry Shen; Harveshp Mogal; Carl Schmidt; Eliza W. Beal; Ioannis Hatzaras; Rivfka Shenoy; Kenneth Cardona; Shishir K. Maithel

Perioperative blood transfusion is associated with poor outcomes in several malignancies. Its effect in gallbladder cancer (GBC) is unknown.


Journal of The American College of Surgeons | 2017

Distal Cholangiocarcinoma and Pancreas Adenocarcinoma: Are They Really the Same Disease? A 13-Institution Study from the US Extrahepatic Biliary Malignancy Consortium and the Central Pancreas Consortium

Cecilia G. Ethun; Alexandra G. Lopez-Aguiar; Timothy M. Pawlik; George A. Poultsides; Kamran Idrees; Ryan C. Fields; Sharon M. Weber; Clifford S. Cho; Robert C.G. Martin; Charles R. Scoggins; Perry Shen; Carl Schmidt; Ioannis Hatzaras; David J. Bentrem; Syed A. Ahmad; Daniel E. Abbott; Hong Jin Kim; Nipun B. Merchant; Charles A. Staley; David A. Kooby; Shishir K. Maithel


Annals of Surgery | 2017

Transplantation Versus Resection for Hilar Cholangiocarcinoma: An Argument for Shifting Treatment Paradigms for Resectable Disease

Cecilia G. Ethun; Alexandra G. Lopez-Aguiar; Douglas J. Anderson; Andrew B. Adams; Ryan C. Fields; M. Doyle; William C. Chapman; Bradley Krasnick; Sharon M. Weber; Joshua D. Mezrich; Ahmed Salem; Timothy M. Pawlik; George A. Poultsides; Thuy B. Tran; Kamran Idrees; Chelsea A. Isom; Robert C.G. Martin; Charles R. Scoggins; Perry Shen; Harveshp Mogal; Carl Schmidt; Eliza W. Beal; Ioannis Hatzaras; Rivfka Shenoy; Kenneth Cardona; Shishir K. Maithel


Annals of Surgical Oncology | 2017

The Oncologic Impact of Postoperative Complications Following Resection of Truncal and Extremity Soft Tissue Sarcomas

Justine S. Broecker; Cecilia G. Ethun; David K. Monson; Alexandra G. Lopez-Aguiar; Nina Le; Mia R. McInnis; Karen D. Godette; Nickolas B. Reimer; Shervin V. Oskouei; Keith A. Delman; Charles A. Staley; Shishir K. Maithel; Kenneth Cardona


Journal of The American College of Surgeons | 2018

Studying a Rare Disease Using Multi-Institutional Research Collaborations vs Big Data: Where Lies the Truth?

Aileen C. Johnson; Cecilia G. Ethun; Yuan Liu; Alexandra G. Lopez-Aguiar; Thuy B. Tran; George A. Poultsides; Valerie P. Grignol; J. Harrison Howard; Meena Bedi; T. Clark Gamblin; Jennifer F. Tseng; Kevin K. Roggin; Konstantinos Chouliaras; Konstantinos I. Votanopoulos; Darren R. Cullinan; Ryan C. Fields; Keith A. Delman; William C. Wood; Kenneth Cardona; Shishir K. Maithel


Journal of Gastrointestinal Surgery | 2018

Surgery Provides Long-Term Survival in Patients with Metastatic Neuroendocrine Tumors Undergoing Resection for Non-Hormonal Symptoms

Jeffery Chakedis; Eliza W. Beal; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola-Smith; Clifford S. Cho; Megan Beems; Timothy M. Pawlik; Shishir K. Maithel; Carl Schmidt; Mary Dillhoff


Journal of Clinical Oncology | 2018

Defining the number of lymph nodes needed to accurately stage small bowel neuroendocrine tumors: An 8-institution study from the US neuroendocrine tumor study group.

Mohammad Zaidi; Alexandra G. Lopez-Aguiar; Mary Dillhoff; Eliza W. Beal; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Angelena Crown; Kamran Idrees; Paula Marincola Smith; Hari Nathan; Megan Beems; Daniel E. Abbott; James R. Barrett; Ryan C. Fields; Jesse T. Davidson; Kenneth Cardona; Shishir K. Maithel

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Ryan C. Fields

Washington University in St. Louis

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Kamran Idrees

Vanderbilt University Medical Center

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Bradley Krasnick

Washington University in St. Louis

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Eliza W. Beal

The Ohio State University Wexner Medical Center

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Mary Dillhoff

The Ohio State University Wexner Medical Center

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Flavio G. Rocha

Brigham and Women's Hospital

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Megan Beems

University of Michigan

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