Ronald P DeMatteo

Memorial Sloan-Kettering Cancer Center, New York City, New York, United States

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Publications (339)1841.91 Total impact

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    ABSTRACT: The role of carcinoembryonic antigen (CEA) in surveillance and follow-up of patients with colorectal cancer continues to be debated. The objective of this study was to assess the utility of postoperative CEA as a predictor of recurrence for patients with resected colorectal liver metastases (CLM). Patients were identified from a prospectively maintained CLM database, and were studied retrospectively. Patients with extrahepatic disease or initially unresectable CLM were excluded. All patients in this study received adjuvant systemic chemotherapy after resection. Between 1997 and 2007, a total of 318 consecutive patients were studied, with 168 patients (53 %) experiencing recurrence within 2 years. Various postoperative CEA cutoffs were tested as independent predictors of recurrence. A postoperative CEA ≥15 ng/ml obtained the highest hazard ratio (1.87; 95 % CI 1.09-3.2; p = 0.023) and was chosen to be included in the survival analysis in the multivariate model. A postoperative CEA ≥15 ng/ml had a specificity of 96 % and positive predictive value of 82 % for recurrence. On multivariate analysis, age ≥70 years, the presence of positive lymph node at primary tumor resection, disease-free interval ≤12 months, number of lesions >1, largest lesion ≥5 cm, presence of positive margins, and postoperative CEA ≥15 ng/ml were independent predictors of recurrence within 2 years. This study demonstrates a postoperative CEA ≥15 ng/ml to be a predictive test for recurrence.
    Annals of Surgical Oncology 01/2015; · 3.94 Impact Factor
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    ABSTRACT: Patients with recurrence after complete resection of colorectal liver metastases (CLM) are considered for repeat resection as a potential salvage therapy (PST). However, outcomes for this approach are not well defined. We sought to analyze the natural history of recurrence and PST in a large cohort of patients with long-term follow-up. Recurrence patterns, treatments, and outcomes in consecutive patients undergoing resection for colorectal liver metastases were analyzed retrospectively. PST was defined as repeat resection of all recurrent disease and effective salvage therapy (EST) as free of disease for 36 months after last PST. Factors associated with PST, EST, and outcomes were analyzed. Of 952 patients who underwent resection, 594 (62 %) experienced recurrence (median interval = 13 months). Initial recurrences involved liver (n = 157,26 %), lung (n = 167,28 %), multiple sites (n = 171,29 %), and other single sites (n = 99,17 %). PST was performed in 160 (27 %) of 594, most commonly with a single site of recurrence (n = 149). Young age (p = 0.01), negative initial resection margin (p = 0.003), initial tumor size <5 cm (p = 0.006), and recurrence pattern (p < 0.001) were independently associated with PST. Thirty-six patients experienced EST (25 % of PSTs). Overall median survival was 61 and 43 months in those with recurrence. Median survival of patients undergoing PST was 87 months compared to 34 months for those who did not. Recurrence is common after CLM resection, but 27 % of patients were able to undergo PST. Approximately one-quarter of these experienced EST and may be cured. PST is associated with long-term survival and possible cure, and therefore active surveillance after CLM resection is justified.
    Annals of Surgical Oncology 01/2015; · 3.94 Impact Factor
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    ABSTRACT: OBJECTIVES:: To evaluate the association of tumor-associated neutrophils (TANs) with malignant progression in intraductal papillary mucinous neoplasms (IPMNs) and to study the cyst fluid from these lesions for biomarkers of the inflammation-carcinogenesis association. BACKGROUND:: There is a strong link between TANs and malignant progression. Inflammatory mediators released by these cells may be a measurable surrogate marker of this progression. METHODS:: We evaluated 78 resected IPMNs (2004-2013). Lesions were divided into the low-risk (low- and intermediate-grade dysplasia: n = 48) and high-risk (high-grade dysplasia and invasive carcinoma: n = 30) groups. TANs were assessed and categorized (negative, low, and high). A multiplexed assay was performed to evaluate 87 different cyst fluid proteins, including cyst fluid inflammatory markers (CFIMs), as possible surrogate markers for parenchymal inflammation. RESULTS:: Significant positive correlation between grade of dysplasia and TANs was found. High levels of TANs were identified in 2%, 33%, and 89% of the lesions when stratified by grade of dysplasia into low/intermediate-grade dysplasia, high-grade dysplasia, and invasive carcinoma, respectively (P < 0.001). Higher grades of dysplasia were also found to have positive correlation with 29 of the measured proteins, of which 23 (79%) were CFIMs. Higher levels of TANs correlated with higher levels of 18 CFIMs, of which 16 (89%) were also found to be associated with higher grades of dysplasia. CONCLUSIONS:: In this study, TANs were strongly associated with malignant progression in IPMNs. Measurement of CFIMs may be a surrogate marker for IPMN progression and allow for the identification of high-risk disease.
    Ann Surg. 01/2015;
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    ABSTRACT: Combined intra-operative ablation and resection (CARe) is proposed to treat extensive colorectal liver metastases (CLM). This multicenter study was conducted to evaluate overall survival (OS), local recurrence-free survival (LRFS), hepatic recurrence-free survival (HRFS) and progression-free survival (PFS), to identify factors associated with survival, and to report complications. Four centers combined retropectively their clinical experiences regarding CLM treated by CARe. CLM characteristics, pre- and post-operative chemotherapy regimens, surgical procedures, complications and survivals were analyzed. Of the 288 patients who received CARe, 210 (73%) had synchronous and 255 (88%) had bilateral CLM. Twenty-two patients (8%) had extrahepatic disease. Median follow-up was 3.17 years (95%CI 2.83-4.08). Median OS was 3.33 years (95%CI 3.08-4.17) and 5-year OS was 37% (95%CI 29-45). One- and 5-year LRFS from ablated lesions were 87.9% (95%CI 83.3-91.2) and 78.0% (95%CI 71-83), respectively. Median HRFS and PFS were 14 months (95%CI 11-18) and 9 months (95%CI 8-11), respectively. One hundred patients experienced complications: 29 grade I, 68 grade II-III-IV, and three deaths. In the multivariate models adjusted for center, the occurrence of complications was confirmed as a major independent factor associated with 3-year OS (HR 1.80; P = 0.008). Five-year OS was 25.6% (95%CI 14.9-37.6) for patients with complications and 45% (95%CI 33.3-53.4) for patients without. Recent strategies facing advanced CLM include non-anatomic resections, portal-induced hypertrophy of the future remnant liver and aggressive medical preoperative treatments. CARe has the qualities of an approach that allows effective tumor clearance while maintaining good tolerance for the patient.
    PLoS ONE 12/2014; 9(12):e114404. · 3.53 Impact Factor
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    ABSTRACT: Texture analysis is a promising method of analyzing imaging data to potentially enhance diagnostic capability. This approach involves automated measurement of pixel intensity variation that may offer further insight into disease progression than do standard imaging techniques alone. We postulated that postoperative liver insufficiency, a major source of morbidity and mortality, correlates with preoperative heterogeneous parenchymal enhancement that can be quantified with texture analysis of cross-sectional imaging. A retrospective case-matched study (waiver of informed consent and HIPAA authorization, approved by the Institutional Review Board) was performed comparing patients who underwent major hepatic resection and developed liver insufficiency (n = 12) with a matched group of patients with no postoperative liver insufficiency (n = 24) by procedure, remnant volume, and year of procedure. Texture analysis (with gray-level co-occurrence matrices) was used to quantify the heterogeneity of liver parenchyma on preoperative CT scans. Statistical significance was evaluated using Wilcoxon's signed rank and Pearson's chi-square tests. No statistically significant differences were found between study groups for preoperative patient demographics and clinical characteristics, with the exception of sex (p < 0.05). Two texture features differed significantly between the groups: correlation (linear dependency of gray levels on neighboring pixels) and entropy (randomness of brightness variation) (p < 0.05). In this preliminary study, the texture of liver parenchyma on preoperative CT was significantly more varied, less symmetric, and less homogeneous in patients with postoperative liver insufficiency. Therefore, texture analysis has the potential to provide an additional means of preoperative risk stratification. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
    Journal of the American College of Surgeons 12/2014; · 4.45 Impact Factor
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    ABSTRACT: Low central venous pressure (LCVP)-assisted hepatectomy is associated with decreased blood loss and lower transfusion rates. Concerns about its impact on renal function have prevented widespread application. This study was conducted to review the dynamics of renal function after LCVP-assisted hepatectomy.
    HPB 11/2014; · 2.05 Impact Factor
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    ABSTRACT: Primary pancreatic lymphoma (PPL) is a rare tumor that is often misdiagnosed. Clinicopathologic features, optimal therapy, and outcomes are not well defined. We reviewed our institutional experience with PPL.
    Annals of Surgical Oncology 10/2014; · 3.94 Impact Factor
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    ABSTRACT: Background The indications for minimally invasive (MIS) pancreatectomy have slowly increased as experience, techniques and technology have improved and evolved to manage malignant lesions in selected patients without compromising safety and oncologic principles. There are sparse data comparing laparoscopic, robotic and open distal pancreatectomy (DP). Study Design All patients undergoing DP at Memorial Sloan Kettering Cancer Center between 2000 and 2013 were analyzed from a prospective database. Clinicopathological and survival data were analyzed to compare perioperative and oncological outcomes in patients who underwent DP via open, laparoscopic and robotic approaches. Results Eight hundred and five DP were performed during the study period, comprising 37 robotic distal pancreatectomies (RDP), 131 laparoscopic distal pancreatectomies (LPD) and 637 open distal pancreatectomies (ODP). The 3 groups were similar with respect to American Society of Anesthesiologists (ASA) score, gender ratio, body mass index, pancreatic fistula rate and 90-day morbidity and mortality. Patients in the ODP group were generally older (p=0.001), had significantly higher intraoperative blood loss (p<0.001) and had a trend towards a longer hospital stay(p=0.05). Of the significant pre-operative variables, visceral fat was predictive of conversion on multivariate analysis (p=0.003). Oncologic outcomes in the adenocarcinoma cases were similar for the 3 groups with high rates of R0 resection (88-100%). The ODP group had a higher lymph node yield than the LDP and RDP groups [15.4, standard deviation (SD) 8.7 vs. 10.4(SD 8.0) vs. 12(SD 7.2),p = 0.04]. Conclusions RDP and LDP were comparable with respect to most perioperative outcomes, with no clear advantage of one approach over the other. Both of these MIS techniques may have advantages over ODP in well-selected patients. All approaches achieved a similar high rate of R0 resection for patients with adenocarcinoma.
    Journal of the American College of Surgeons 10/2014; · 4.45 Impact Factor
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    ABSTRACT: Choledochal cysts (CDCs) are believed to represent a risk factor for the development of neoplasia. However, the frequency and morphology of neoplastic changes have not been systematically studied, especially in North America. Our aims were to study the frequency and morphology of preneoplastic/neoplastic changes of CDCs. 36 cysts were subjected to clinicopathological analyses. Metaplasia was found in 14/35, of which 9 had Biliary Intraepithelial Neoplasia (BilIN). Of the 14 with metaplasia, 13 showed pyloric gland (PG), 5 intestinal (IN), and 2 squamous. BilINs included 6 BilIN-1, 2 BilIN-2, and 2 BilIN-3. Carcinoma was identified in 5 cases of which 3 were associated with metaplasia and BilIN. Only 1/18 cases without metaplasia had BilIN and none had carcinoma (p=0.0008). There was a trend towards more BilIN and carcinoma with intestinal rather than with pyloric gland metaplasia. All cases with metaplasia or/and BilIN were negative for MUC1. All cases with intestinal metaplasia were positive for CK20, CDX2, and MUC2, whereas cases with pyloric gland were positive for MUC6. MUC1, CEA and B72.3 were positive only in carcinoma. There was a trend toward increasing p53 and ki-67 from metaplasia to BilIN to carcinoma. 4/5 patients with carcinoma died and one was alive with disease. All others were free of disease except for one who developed new cysts. CDCs are associated with a high rate of BilIN (28.5%) and carcinoma (14.3%). CDCs show a sequence of tumor progression from metaplasia to BilIN and carcinoma.
    Human pathology 10/2014; · 2.81 Impact Factor
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    ABSTRACT: Objectives This study was conducted to evaluate the prognostic value of, respectively, the 6th and 7th editions of the American Joint Committee on Cancer (AJCC) staging system for patients with resected perihilar cholangiocarcinoma (PHC).Methods Patients who underwent resection of PHC between 1991 and 2012 were identified from prospective databases at two centres. Overall survival was estimated using the Kaplan–Meier method and compared across stage groups with the log-rank test. The concordance index and Brier score were used to compare the prognostic accuracy of the staging systems.ResultsData for a total of 306 patients were analysed. Staging according to the 7th edition upstaged 63% of patients in comparison with staging by the 6th edition. The log-rank P-value for both staging systems was highly statistically significant (P < 0.001). Staging according to the 6th edition categorized 93% of patients as having stage I or II disease, whereas staging according to the 7th edition distributed patients more equally across stages. Prognostic accuracy was similar between the staging systems: the concordance index was 0.59 and the Brier score 0.17 for both the 6th and 7th editions. The same prognostic accuracy was achieved using an alternative tumour–node–metastasis (TNM) stage grouping simplified to four rather than six stage groups.Conclusions The 6th and 7th editions of the AJCC staging system for PHC have similar prognostic accuracy. Other prognostic factors can potentially improve individual patient prognostication.
    HPB 10/2014; · 2.05 Impact Factor
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    ABSTRACT: Background After portal vein embolization (PVE), the future liver remnant (FLR) hypertrophies over several weeks. An early marker that predicts a low risk of post-hepatectomy liver failure may reduce the delay to surgery. Study Design Liver volumes of 153 patients who underwent a major hepatectomy (>3 segments) after PVE for primary or secondary liver malignancy between September 1999 and November 2012 were retrospectively evaluated with computerized volumetry. Pre- and post-PVE FLR volume and functional liver volume (FLV) were measured. Degree of hypertrophy (DH = postFLR/postFLV - preFLR/preFLV) and growth rate (GR = DH / weeks since PVE) were calculated. Postoperative complications and liver failure were correlated with DH, measured GR, and estimated GR (eGR) derived from a formula based on body surface area. Results Eligible patients underwent 93 right hepatectomies, 51 extended right hepatectomies, 4 left hepatectomies, and 5 extended left hepatectomies. Major complications occurred in 44 patients (28.7%) and liver failure in 6 patients (3.9%). Non-parametric regression showed that post-embolization FLR% correlated poorly with liver failure. ROC curves showed that DH and GR were good predictors of liver failure (AUC=0.80, p=0.011, and AUC=0.79, p=0.015) and modest predictors of major complications (AUC=0.66, p=0.002, and AUC=0.61, p=0.032). No patient with GR >2.66%/wk developed liver failure. The predictive value of measured GR was superior to eGR for liver failure (AUC 0.79 vs 0.58, p=0.046). Conclusions Both DH and GR after PVE are strong predictors of post-hepatectomy liver failure. GR may be a better guide for the optimum timing of liver resection than static volumetric measurements. Measured volumetrics correlated with outcomes better than estimated volumetrics.
    Journal of the American College of Surgeons 10/2014; · 4.45 Impact Factor
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    ABSTRACT: Background Residual disease (RD) at definitive resection of incidental gallbladder cancer (IGBCA) influences outcome, but its clinical relevance with respect to anatomic site is incompletely characterized. Study Design Consecutive patients with IGBCA undergoing re-exploration from 1998-2009 were identified; those submitted to a complete resection were analyzed. Demographics, tumor- and treatment-related variables were correlated with RD and survival. Cancer-specific survival was stratified by site of RD [local (gallbladder bed); regional (bile duct, lymph nodes); distant (discontiguous liver, port site, peritoneal)]. Results Of the 135 patients submitted to re-exploration, RD was found in 82 (61%) overall and in 63 (54%) of 116 patients submitted to resection; the most common site was regional (N=27, 43%). T stage of the gallbladder specimen was the only independent predictor of RD (T1b=35.7%,T2=48.3%,T3=70%,p=0.015). The presence of RD at any site dramatically reduced median disease-free survival (DFS) (11.2 vs. 93.4 months, p<0.0001) and disease-specific survival (DSS) (25.2 months vs. not reached, p<0.0001) compared to no RD, respectively. DSS did not differ according to RD location, with all anatomic sites being equally poor (p=0.87). RD at any site predicted DFS (HR 3.3, 95% CI 1.9-5.7, p=0.0003) and DSS (HR 2.4, 95% CI 1.2-4.6, p=0.01), independent of all other tumor-related variables. Conclusions Survival in patients with RD at local or regional sites was not significantly different than that seen in stage IV disease, with neither subgroup clearly benefiting from reoperation. Outcome was poor in all patients with RD, regardless of location.
    Journal of the American College of Surgeons 09/2014; · 4.45 Impact Factor
  • Vinod P. Balachandran, Ronald P. DeMatteo
    Advances in Surgery. 09/2014;
  • Journal of the American College of Surgeons 09/2014; 219(3):S24. · 4.45 Impact Factor
  • Vinod P Balachandran, Ronald P DeMatteo
    Annals of Surgical Oncology 08/2014; · 3.94 Impact Factor
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    ABSTRACT: Background The reliable prediction of hepatocellular carcinoma (HCC) recurrence patterns potentially allows for the prioritization of patients for liver resection (LR) or transplantation.Objectives The aim of this study was to analyse clinicopathological factors and preoperative Milan criteria (MC) status in predicting patterns of HCC recurrence.Methods During 1992–2012, 320 patients undergoing LR for HCC were categorized preoperatively as being within or beyond the MC, as were recurrences.ResultsAfter a median follow-up of 47 months, 183 patients developed recurrence, giving a 5-year cumulative incidence of recurrence of 62.5%. Patients with preoperative disease within the MC had better survival outcomes than those with preoperative disease beyond the MC (median survival: 102 months versus 45 months; P < 0.001). Overall, 31% of patients had preoperative disease within the MC and 69% had preoperative disease beyond the MC. Estimated rates of recurrence-free survival at 5 years were 61.8% for all patients and 53.8% for patients with initial beyond-MC status. Independent factors for recurrence beyond-MC status included preoperative disease beyond the MC, the presence of microsatellite or multiple tumours and lymphovascular invasion (all: P < 0.001). A clinical risk score was used to predict survival and the likelihood of recurrence beyond the MC; patients with scores of 0, 1, 2 and 3 had 5- year incidence of recurring beyond-MC of 9.0%, 29.5%, 48.8% and 75.4%, respectively (P < 0.0001).Conclusions Regardless of initial MC status, at 5 years the majority of patients remained disease-free or experienced recurrence within the MC after LR, and thus were potentially eligible for salvage transplantation (ST). Incorporating clinicopathological parameters into the MC allows for better risk stratification, which improves the selection of patients for ST and identifies patients in need of closer surveillance.
    HPB 08/2014; · 2.05 Impact Factor
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    ABSTRACT: Readmission rates have been targeted for cost/reimbursement control. Our goal was to identify causes for readmission and delineate the pattern of early and late readmission.
    Annals of Surgical Oncology 07/2014; · 3.94 Impact Factor
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    ABSTRACT: Background Current pre-operative staging methods for gallbladder cancer (GBC) are suboptimal in detecting metastatic disease. Positron emission tomography (PET) may have a role but data are lacking.Methods Patients with GBC and PET assessed by a hepatobiliary surgeon in clinic between January 2001 and June 2013 were retrospectively reviewed. Computed tomography (CT)/magnetic resonace imaging (MRI) were correlated with PET scans and analysed for evidence of metastatic or locally unresectable disease. Medical records were reviewed to determine if PET scanning was helpful by preventing non-therapeutic surgery or enabling resection in patients initially deemed unresectable.ResultsThere were 100 patients including 63 incidental GBC. Thirty-eight patients did not proceed to surgery, 35 were resected and 27 patients were explored but had unresectable disease. PET was positive for metastatic disease in 39 patients (sensitivity 56%, specificity 94%). Five patients definitively benefitted from PET: in 3 patients PET found disease not seen on CT, and 2 patients with suspicious CT findings had negative PET and successful resections. In a further 12 patients PET confirmed equivocal CT findings. Three patients had additional invasive procedures performed owing to PET avidity in other sites. Utility of PET was higher in patients with suspicious nodal disease on CT [odds ratio (OR) 7.1 versus no nodal disease, P = 0.0004], and in patients without a prior cholecystectomy (OR 3.1 versus post-cholecystectomy, P = 0.04).Conclusion Addition of PET to conventional cross-sectional imaging has a modest impact on management pre-operatively particularly in patients without a prior cholecystectomy and to confirm suspicious nodal disease on CT.
    HPB 07/2014; · 2.05 Impact Factor
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    ABSTRACT: The role for neoadjuvant systemic therapy in resectable pancreas adenocarcinoma remains undefined.
    Annals of Surgery 07/2014; 260(1):142-148. · 7.19 Impact Factor
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    ABSTRACT: BACKGROUND The validity of the KRAS mutation as a predictor of recurrence-free survival (RFS) or overall survival (OS) is unclear. The current study investigated whether the presence of the KRAS mutation decreased RFS or OS in patients with colorectal cancer who underwent liver resection.METHODS Patients with resected colorectal liver metastases who received adjuvant hepatic arterial infusion plus systemic therapy and for whom KRAS data was available were evaluated. Correlation between KRAS and clinical factors was done using the Fisher exact test. Kaplan-Meier methods were used to estimate the median RFS and OS.RESULTSA total of 169 patients were evaluated, 118 of whom had KRAS wild-type (WT) and 51 had KRAS mutated (MUT) tumors. The 3-year RFS rate was 46% for patients with KRAS WT (95% confidence interval [95% CI], 35%-56%) and 30% (95% CI, 16%-44%) for patients with KRAS MUT (P =.005). The 3-year OS rate was 95% (95% CI, 87%-98%) and 81% (95% CI, 62%-95%), respectively, for patients with KRAS WT and KRAS MUT (P =.07). On multivariate analysis, KRAS remained a significant predictor of RFS (hazard ratio, 1.9). The 3-year cumulative recurrence rate by site of metastases was as follows: 2% versus 13.4% for bone (P≤.01), 2% versus 14.5% for brain (P =.05), 33.2% versus 58% for lung (P≤.01), and 30% versus 47% for liver (P =.10) in patients with KRAS WT versus KRAS MUT.CONCLUSIONS In the current study, among patients with resected colorectal liver metastases who were treated with adjuvant hepatic arterial infusion plus systemic therapy, patients with KRAS MUT were found to have a significantly worse 3-year RFS (30%) compared with KRAS WT (46%) p=.005. The cumulative incidence of bone, brain, and lung metastases was significantly higher for patients with KRAS MUT compared with those with KRAS WT. Cancer 2014. © 2014 American Cancer Society.
    Cancer 07/2014; · 5.20 Impact Factor

Publication Stats

12k Citations
1,841.91 Total Impact Points


  • 2000–2014
    • Memorial Sloan-Kettering Cancer Center
      • • Department of Surgery
      • • Department of Pathology
      • • Hepatopancreatobiliary Service
      New York City, New York, United States
  • 2010–2013
    • Emory University
      • Department of Surgery
      Atlanta, Georgia, United States
    • Weill Cornell Medical College
      New York City, New York, United States
    • University of Ottawa
      • Department of Surgery
      Ottawa, Ontario, Canada
    • University of Manitoba
      • Department of Surgery
      Winnipeg, Manitoba, Canada
    • National and Kapodistrian University of Athens
      • Division of Surgery V
      Athens, Attiki, Greece
  • 2012
    • University of Colorado
      • Department of Surgery
      Denver, CO, United States
    • Helsinki University Central Hospital
      • Department of Oncology
      Helsinki, Province of Southern Finland, Finland
  • 2011
    • San Antonio Military Medical Center
      Texas City, Texas, United States
    • University of Illinois at Chicago
      • Department of Surgery (Chicago)
      Chicago, IL, United States
    • Naval Hospital Camp Pendleton
      Camp Pendleton North, California, United States
    • Boston University
      • Department of Surgery
      Boston, MA, United States
    • Lenoir Memorial Hospital
      North Carolina, United States
    • Universität Heidelberg
      • Department of General, Visceral and Transplantation Surgery
      Heidelberg, Baden-Wuerttemberg, Germany
  • 2010–2011
    • University of Texas Southwestern Medical Center
      • Division of Surgical Oncology
      Dallas, TX, United States
  • 2009
    • Robert Wood Johnson University Hospital
      New Brunswick, New Jersey, United States
    • Houston Methodist Hospital
      Houston, Texas, United States
  • 2008
    • University of Wisconsin–Madison
      • Department of Surgery
      Madison, Wisconsin, United States
    • Indiana University Bloomington
      • Department of Surgery
      Bloomington, IN, United States
  • 2007
    • The University of Edinburgh
      Edinburgh, Scotland, United Kingdom
  • 2006
    • San Giovanni Hospital Complex
      Roma, Latium, Italy
    • Indiana University-Purdue University Indianapolis
      • Department of Surgery
      Indianapolis, IN, United States
    • Massachusetts General Hospital
      • Division of Surgical Oncology
      Boston, MA, United States
  • 2005
    • Yale University
      • Department of Surgery
      New Haven, CT, United States
  • 2004
    • Brigham and Women's Hospital
      • Department of Medicine
      Boston, MA, United States
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States
  • 2003
    • University of Louisville
      Louisville, Kentucky, United States