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Gudmundsdottir, Hallbera

https://orcid.org/0000-0002-1297-2769

Mayo Clinic

Mayo Clinic

Citations 15

Outcomes of liver resections for neuroendocrine tumor liver metastases in carcinoid heart disease
Ammann, M, Podrascanin, Vanja, Pereyra, David, Dong, Yawen , Connolly, Heidi M. , Schaff, Hartzell V., Warner, Susanne G, Truty, M., Kendrick, Michael L. , Smoot, Rory L., Nagorney, David M. , Ammann, Markus , Santol, Jonas , Dong, Yawen , Halfdanarson, Thorvardur R , Gudmundsdottir, Hallbera , Podrascanin, V. , Santol, Jonas , Pellikka, Patricia A. , Crestanello, Juan A. , Thiels, Cornelius A. , Warner, Susanne G. , Truty, Mark J. , Hálfdánarson, Þorvarður R. , Starlinger, Patrick

Journal of Neuroendocrinology | July 1, 2026 | Volume: 38 | Issue: 7 | Pages: No page available

10.1111/jne.70226 Get It

Abstract Carcinoid heart disease (CHD) is associated with advanced neuroendocrine tumor liver metastases (NETLM) and may preclude surgical cytoreduction. We assessed perioperative and long‐term outcomes of hepatectomy in patients with CHD. We retrospectively analyzed 311 patients undergoing cytoreductive hepatectomy for intestinal NETLM: non‐functional ( n = 163), carcinoid syndrome (CS) without CHD ( n = 110), and CHD ( n = 38), including patients undergoing pre‐hepatectomy valve replacement. CHD patients more frequently had >10 liver metastases (78%) and larger lesions (median 9.5 cm) and required major hepatectomy more often (58%). Major morbidity was higher in CHD (up to 47%), yet 90‐day mortality remained low (≤4%). Median overall survival after hepatectomy was comparable across groups (12.5 vs. 9.1 vs. 11.4 years; p = .19), including matched analyses. With optimal cardiac management, cytoreductive hepatectomy in CHD is feasible and provides long‐term survival comparable to patients without CHD.
International Reference Values for Surgical Outcomes of Total Pancreatectomy
Berchtold, Caroline , Kuemmerli, Christoph, Li, Zhihao , Eden, Janina , Wu, Pengfei , Cecchetto, Sara Nicole, Kendrick, Michael L. , Pecorelli, Nicolò , Guarneri, Giovanni , Farooqui, Waqas , Tschuor, Christoph , Burgdorf, Stefan Kobbelgaard , Mühlhäusser, Julia , Gass, Jörn‐Markus , Koh, Ye-Xin, Seip, Tomas, Santibañes, Martín de , Todeschini, Letizia , Marchegiani, Giovanni, Belfil, Nadiya , Boggi, Ugo, Cappelle, Marie , Koerkamp, Bas Groot , Dutkowski, Philipp , Hackert, Thilo , Truty, Mark J. , Group, Outcomes for Total Pancreatectomy, Valle, Valentina , Giulianotti, Pier Cristoforo , Pessaux, Patrick, Thapa, Prabin , Kuzman, Matta , Pandanaboyana, Sanjay, He, Jin , Kendrick, Michael, Truty, Mark, Li, Zhihao , Groot Koerkamp, Bas , Müller, Philip C , Breuer, Eva , Vallorani, Alessia , Hansen, Carsten Palnæs , Guidetti, Cristiano , Campbell, Brady A. , Cecchetto, Sara Nicole, Gudmundsdottir, Hallbera , Starlinger, Patrick , Goh, Brian K P , Koh, Ye-Xin , Rebelo, Artur , Kleeff, Jorg H. , Marchegiani, Giovanni , Lesurtel, Mickaël , Machado, Marcel Autran C. , Kauffmann, Emanuele F. , Benedetto, Fabrizio Di , Roberts, Keith John , Nevler, Avinoam , Lavu, Harish , Nickel, Felix , He, Jing , Falconi, Massimo , Billeter, Adrian T. , Müller-Stich, Beat Peter , Group, Outcomes for Total Pancreatectomy, Halle-Smith, James Michael , Giannone, Fabio , Pessaux, Patrick , Sánchez‐Velázquez, Patricia , Maharjan, Dhiresh Kumar , Torres, Orlando Jorge Martins

JAMA Surgery | November 12, 2025 | Volume: 161 | Issue: 1 | Pages: 50

10.1001/jamasurg.2025.4941 Get It

Importance Total pancreatectomy (TP) is indicated for advanced pancreatic cancer or multifocal tumors. Furthermore, TP may be performed to avoid the risk of pancreatic fistula in selected patients to improve the perioperative risk profile. Objective To define reference values for TP based on a low-risk cohort treated at expert centers. Design, Setting, and Participants This multicenter study analyzed outcomes from patients undergoing primary TP for malignant or benign lesions from 25 international expert centers from January 2017 to November 2023. Low-risk patients undergoing TP (LR-TP) were without vascular resections or significant comorbidities. Exposures TP. Main Outcomes and Measures Twenty reference values were derived from the 75th or the 25th percentile of the median values of all centers. Outcomes of LR-TP were compared with a cohort of TP with vascular resection, TP due to high-risk pancreatic anastomosis, and the benchmark values for low-risk pancreatoduodenectomy. Results Of 994 patients, 333 (33.5%; median [IQR] age, 66 [58-72] years; 171 male [51.4%]) qualified as the LR-TP cohort. Reference values included blood loss (≤1000 mL), major complications (≤37%), 3-month postoperative mortality (<6%), and retrieved lymph nodes (≥29). Compared with TP with vascular resections, reference cutoffs were not met for major complications (51% vs LR-TP ≤37%) and 90-day mortality (11% vs LR-TP ≤6%). For TP due to high-risk anastomosis, failure to rescue rate (38% vs ≤6%) and 90-day mortality (11% vs LR-TP ≤6%) were not met. Compared with pancreatoduodenectomy, reference values for postoperative mortality were 3 times higher for LR-TP (≤2% vs ≤6%) and less for resected lymph nodes (≥16 vs ≥29). Conclusions and Relevance This case-control study provided global reference values for TP, indicating significantly higher postoperative morbidity and mortality compared with pancreatoduodenectomy. Perioperative morbidity of TP was especially increased in patients with vascular resections. These reference values can serve for quality control of pancreatic surgery.
Evolution of the Indications and Outcomes of Total Pancreatectomy
Antwi, Stella K Adjei, Warner, Susanne G, Smoot, Rory L. , Kendrick, Michael L. , Truty, Mark J. , Smoot, Rory L , Gudmundsdottir, Hallbera , Thiels, Cornelius A. , Warner, Susanne G. , Starlinger, Patrick

Journal of the American College of Surgeons | November 6, 2025 | Volume: 242 | Issue: 2 | Pages: 259-270

10.1097/xcs.0000000000001642 Get It

BACKGROUND: The first total pancreatectomy (TP) resulting in survival past the immediate postoperative period was performed at Mayo Clinic in 1944. Although still uncommonly performed, indications have recently fluctuated. We aimed to evaluate trends in TP use and outcomes over four decades. STUDY DESIGN: Patients who underwent single-stage TP at Mayo Clinic Rochester from 1988 to 2024 were analyzed in two cohorts: early era (EE, 1988 to 2009) and modern era (ME, 2010 to 2024). RESULTS: In total, 437 patients were identified: 118 during EE (mean 8 per year) and 319 during ME (mean 21 per year). Primary indications were adenocarcinoma (42% EE vs 60% ME), intraductal papillary mucinous neoplasm (31% EE vs 17% ME), and chronic pancreatitis (11% EE vs 13% ME; p < 0.001). Concurrent vascular resection was performed in 9.3% (EE; all venous only) vs 53% (ME; venous alone in 20% and arterial with or without venous in 33%; p < 0.001). Multivisceral resection was performed in <1% (EE) vs 24% (ME; p < 0.001). Major complications occurred in 13% (EE) vs 27% (ME; p = 0.018), and 90-day mortality was 3.4% (EE) vs 6.3% (ME; p = 0.35). For adenocarcinoma, 5-year median overall survival from both surgery and diagnosis was significantly improved in ME (p = 0.009 and p < 0.001, respectively). Median last HbA1c was 7.7 (EE) vs 7.3 (ME; p < 0.001). Among patients surviving more than 1 year, insulin pumps were used in 12% (EE) vs 49% (ME; p < 0.001). Conclusions: The use of TP has dramatically increased in recent years, primarily for adenocarcinoma alongside increased use of neoadjuvant therapy and ever-expanding criteria for anatomic resectability. Operative complexity has significantly increased with resultant increased perioperative morbidity. TP remains a higher-risk procedure, specifically with en bloc vascular resections, emphasizing the importance of appropriate patient selection, preoperative patient education, and thoughtful postoperative and long-term management.
Comparative efficacy of systemic therapies in malignant insulinoma
Koch, Regina M. , Vella, Adrian, Shah, Pankaj, Hobday, Timothy J. , Sonbol, Mohamed Bassam, Starr, Jason S. , Eiring, Rachel A. , McKenzie, Travis J. , Sada, Alaa , Koch, Regina , Starr, Jason , Gudmundsdottir, Hallbera , Eiring, Rachel A , McGarrah, Patrick W. , Shah, Pankaj, Starlinger, Patrick , Gudmundsdottir, Hallbera , Hálfdánarson, Þorvarður R.

Endocrine-Related Cancer | May 29, 2025 | Volume: 32 | Issue: 6 | Pages: No page available

10.1530/erc-25-0091 Get It

Abstract Malignant insulinomas are rare pancreatic neuroendocrine tumors characterized by excessive insulin secretion and a high propensity for metastasis, leading to challenging management. This study retrospectively analyzed 57 patients treated for malignant insulinoma at Mayo Clinic sites between 1992 and 2024, focusing on the efficacy of systemic therapies in improving hypoglycemic control and survival outcomes. The most commonly used therapies included somatostatin analogs (SSA), everolimus, capecitabine-temozolomide (CAPTEM), and peptide receptor radionuclide therapy (PRRT). PRRT demonstrated the highest efficacy in controlling hypoglycemia (93%), followed by CAPTEM (68%) and everolimus (62%). SSA, chemotherapy, and streptozocin were less effective, with hypoglycemic improvement seen in 37.5, 33.3, and 28.6% of patients, respectively. Overall survival (OS) was longest with SSA at 84.67 months, followed by CAPTEM at 81.67 months and everolimus at 74.07 months. PRRT demonstrated a median OS of 49.73 months. In contrast, chemotherapy and streptozocin-based therapies had significantly shorter OS times of 15.23 and 8.35 months, respectively. These findings highlight significant variability in systemic therapy efficacy for malignant insulinoma, with PRRT emerging as a promising treatment for refractory hypoglycemia and long survival. Cox regression analysis identified primary tumor resection and a history of benign insulinoma as associated with longer OS. Optimal sequencing of therapies remains unclear, and individualized treatment plans based on hypoglycemic burden and tumor characteristics are critical for improving survival and quality of life in these patients.
Appendectomy vs Right Hemicolectomy for Pediatric Neuroendocrine Tumor of the Appendix in a National Cohort: A Call to Further Decrease Colectomy
Potter, D. Dean , Day, Courtney N. , Raikot, Swathi R. , Potter, Donald Dean, Gudmundsdottir, Hallbera , Polites, Stephanie F. , Allen‐Rhoades, Wendy , Habermann, Elizabeth B.

Journal of the American College of Surgeons | May 5, 2025 | Volume: 241 | Issue: 4 | Pages: 620-625

10.1097/xcs.0000000000001435 Get It

BACKGROUND: Children continue to undergo right hemicolectomy (RHC) for neuroendocrine tumors (NET) of the appendix based on adult guidelines. Appendectomy alone is recommended for the pediatric population; however, there are no data on safety of this approach in the setting of positive margins. This study aimed to determine the association between tumor characteristics and survival in a national cohort, hypothesizing that survival would be excellent despite high-risk features including positive margins on appendectomy. STUDY DESIGN: Patients 18 years of age or younger with NET of the appendix were identified in the National Cancer Database from 2004 to 2022 using ICD-O-3 codes. Characteristics of patients who underwent definitive appendectomy vs RHC were compared using chi-square tests. Five-year survival was determined for appendectomy patients with and without high-risk size, margin, and lymph node (LN) features. RESULTS: Of 1,339 patients, 1,156 (86%) underwent appendectomy and 183 (14%) RHC. Median age in both groups was 15 (13 to 17) years. Patients who underwent RHC had larger tumors (24% vs 4%, greater than 2 cm, p < 0.001), more lymphovascular invasion (31% vs 10%, p < 0.001), and were more likely to undergo LN assessment (82% vs 10%, p < 0.001) with a higher LN positivity rate (31% vs 16%, p = 0.006). There was no difference in margins status (p = 0.76). The 5- and 10-year survival was excellent regardless of tumor characteristics for patients overall (99.9% and 99.4%, respectively) and for those who underwent definitive appendectomy (99.9% and 99.2%). CONCLUSIONS: These data further support appendectomy as definitive management for children with appendiceal NET. Additional resection does not confer a survival benefit even in the setting of positive margins.
Pancreatic Neuroendocrine Tumors—A Descriptive Study of the Presenting Features in a 20-Year Surgical Resection Cohort at a Tertiary Institution
Singh, Jassimran , Kendrick, Michael L. , Truty, Mark J. , Smoot, Rory L. , Nagorney, David M. , Vege, Santhi Swaroop, Smoot, Rory L , Gudmundsdottir, Hallbera , Hálfdánarson, Þorvarður R. , Cleary, Sean P. , Vege, Santhi Swaroop

Pancreas | May 2, 2025 | Volume: 54 | Issue: 5 | Pages: e423-e429

10.1097/mpa.0000000000002452 Get It

Objectives: Pancreatic neuroendocrine tumors (pNETs) are uncommon, comprising 3%–7% of pancreatic tumors. With increasing incidence due to advanced imaging techniques, there is a need for detailed characterization of these tumors. This study aims to describe the clinical features, diagnostic evaluations, and pathology characteristics of pNETs in a large cohort from a single tertiary center, and to compare these findings with other larger cohort studies. Methods: We conducted a retrospective analysis of 866 patients with pNETs who underwent surgical resection at Mayo Clinic, Rochester, from March 2000 to December 2019. Data on demographics, clinical presentation, laboratory tests, imaging, and pathology were extracted and analyzed. Descriptive statistics were used to summarize the data. Results: The cohort had a median age of 57 years. Nonfunctional tumors were much more prevalent (77.5%), with functional tumors primarily being insulinomas (75.9%). Common presenting symptoms included gastrointestinal (45.3%) and nongastrointestinal symptoms (30.7%). Chromogranin A levels were elevated in 57.5% of patients. Imaging revealed enhancing lesions in most cases, with computed tomography scans performed in 90.9% of patients. Endoscopic ultrasound (EUS) identified tumors in 98.1% of cases, with EUS-FNA showing a sensitivity of 82%. Ki-67 index, used in 58.1% of cases, indicated grade 2 tumors as the most common (55.9%). Metastasis was observed in 39.4% of patients at the time of diagnosis, predominantly in the liver. Conclusion: This study provides a comprehensive description of pNET characteristics in a large surgical cohort. Findings highlight the predominance of nonfunctional tumors and the importance of imaging and EUS in diagnosis. The data can aid in inter-institutional comparisons and enhance understanding of pNETs, contributing to improved patient management and future research.
Alternative lengthening of telomeres and Ki‐67 proliferation index provide complementary information on recurrence risk after resection of pancreatic neuroendocrine tumors
Gudmundsdottir, Hallbera , Knudson, Ryan A., Brandt, Colin T., Smoot, Rory L., Truty, Mark J. , Kendrick, Michael L. , Nagorney, David M. , Smoot, Rory L. , Brandt, Carrie A, Smoot, Rory L , Gudmundsdottir, Hallbera , Graham, Rondell P. , Greipp, Patricia T. , Habermann, Elizabeth B. , Starlinger, Patrick , Thiels, Cornelius A. , Warner, Susanne G. , Cleary, Sean P. , Hálfdánarson, Þorvarður R.

Journal of Neuroendocrinology | February 13, 2025 | Volume: 37 | Issue: 4 | Pages: No page available

10.1111/jne.70003 Get It

Abstract Given the heterogeneous clinical behavior of pancreatic neuroendocrine tumors (pNETs), improved prognostic markers are needed to guide management and post‐resection surveillance. Patients who underwent resection of large (≥3 cm) sporadic well‐differentiated pNETs from 2000 to 2019 were identified. The Ki‐67 proliferation index was determined using immunohistochemistry, and alternative lengthening of telomeres (ALT) status was assessed using fluorescence in situ hybridization. Recurrence‐free and overall survival were estimated using Kaplan–Meier analysis. Multivariable Cox regression analysis evaluated factors associated with recurrence‐free survival. A total of 106 patients were identified. ALT was positive in 57 (54%) and negative in 49 (46%). Ki‐67 was ≥3% in 74 (70%) and <3% in 32 (30%). Tumors with Ki‐67 ≥3% were more likely to be ALT positive (61% vs. 38%, p = .046). Stratifying by ALT status and Ki‐67 proliferation index, median recurrence‐free survival was 4.6 years for patients with ALT‐positive/Ki‐67 ≥3% tumors, 3.1 years for patients with ALT‐positive/Ki‐67 <3% tumors, 12.4 years for patients with ALT‐negative/Ki‐67 ≥3% tumors, and 20.2 years for patients with ALT‐negative/Ki‐67 <3% tumors ( p < .001). Initial recurrence was distant in 82% and locoregional in 18%. Across all groups, overall survival was similar ( p = .19). In multivariable analysis, advanced age, ALT positivity, perineural invasion, and lymph node metastases were associated with increased recurrence risk (all p < .05). ALT and Ki‐67 provide complementary information on post‐resection recurrence risk, which can guide subsequent surveillance and management strategies. These data support the incorporation of ALT testing into routine clinical practice.
Gender Differences in Autonomy Granted to Residents and Fellows During Procedural Training: A Systematic Review and Meta-Analysis
Lund, Sarah , Griffeth, Elaine M. , Williamson, Andrea J.H. , Collings, Amelia T. , Gudmundsdottir, Hallbera , Han, Amy , Kearse, LaDonna , Kratzke, Ian M. , Wilkins, Parvathi , Prokop, Larry J. , Cook, David A. , Williamson, Andrea , Collings, Amelia , Prokop, Larry , Kearse, LaDonna E , Gudmundsdottir, Hallbera

Academic Medicine | August 2, 2024 | Volume: 99 | Issue: 8 | Pages: 922-930

10.1097/acm.0000000000005673 Get It

Abstract Purpose Supervisors may be prone to implicit (unintentional) bias when granting procedural autonomy to trainees due to the subjectivity of autonomy decisions. The authors aimed to conduct a systematic review and meta-analysis to assess the differences in perceptions of procedural autonomy granted to physician trainees based on gender and/or race. Method MEDLINE, Embase, CENTRAL, Scopus, and Web of Science were searched (search date: January 5, 2022) for studies reporting quantitative gender- or race-based differences in perceptions of procedural autonomy of physician trainees. Reviewers worked in duplicate for article selection and data abstraction. Primary measures of interest were self-reported and observer-rated procedural autonomy. Meta-analysis pooled differences in perceptions of procedural autonomy based on trainee gender. Results The search returned 2,714 articles, of which 16 were eligible for inclusion. These reported data for 6,109 trainees (median, 90 per study) and 2,763 supervisors (median, 54 per study). No studies investigated differences in perceptions of autonomy based on race. In meta-analysis of disparities between genders in autonomy ratings (positive number favoring female trainees), pooled standardized mean differences were −0.12 (95% confidence interval [CI], −0.19 to −0.04; P = .003; n = 10 studies) for trainee self-rated autonomy and −0.05 (95% CI, −0.11 to 0.01; P = .07; n = 9 studies) for supervisor ratings of autonomy. Conclusions Limited evidence suggests that female trainees perceived that they received less procedural autonomy than did males. Further research exploring the degree of gender- and race-based differences in procedural autonomy, and factors that influence these differences is warranted.
Perioperative Platelet Count Ratio Predicts Long-Term Survival after Left Pancreatectomy and Splenectomy for Pancreatic Adenocarcinoma
Nachmany, Ido , Meiri, Hila, Eidelman, Pavel , Ziv, Ofir, Bear, Lior, Jacoby, Harel , Eshkenazy, Rony, Pery, Ron, Pencovich, Niv , Gudmundsdottir, Hallbera , Nevo, Nadav

Journal of Clinical Medicine | February 12, 2024 | Volume: 13 | Issue: 4 | Pages: 1050

10.3390/jcm13041050 Get It

Background: The value of platelet characteristics as a prognostic factor in patients with pancreatic adenocarcinoma (PDAC) remains unclear. Methods: We assessed the prognostic ability of post-splenectomy thrombocytosis in patients who underwent left pancreatectomy for PDAC. Perioperative platelet count ratio (PPR), defined as the ratio between the maximum platelet count during the first five days following surgery and the preoperative level, was assessed in relation to long-term outcomes in patients who underwent left pancreatectomy for PDAC between November 2008 and October 2022. Results: A comparative cohort of 245 patients who underwent pancreaticoduodenectomy for PDAC was also evaluated. The median PPR among 106 patients who underwent left pancreatectomy was 1.4 (IQR1.1, 1.8). Forty-six had a PPR ≥ 1.5 (median 1.9, IQR1.7, 2.4) and 60 had a PPR < 1.5 (median 1.2, IQR1.0, 1.3). Patients with a PPR ≥ 1.5 had increased median overall survival (OS) compared to patients with a PPR < 1.5 (40 months vs. 20 months, p < 0.001). In multivariate analysis, PPR < 1.5 remained a strong predictor of worse OS (HR 2.24, p = 0.008). Among patients who underwent pancreaticoduodenectomy, the median PPR was 1.1 (IQR1.0, 1.3), which was significantly lower compared to patients who underwent left pancreatectomy (p > 0.001) and did not predict OS. Conclusion: PPR is a biomarker for OS after left pancreatectomy for PDAC. Further studies are warranted to consolidate these findings.
Accuracy of DOTATATE PET imaging in the preoperative planning of small bowel neuroendocrine tumor resection
Zhang, Chi , Gudmundsdottir, Hallbera , Takahashi, Hiroaki , Day, Courtney N. , Glasgow, Amy E. , Wasif, Nabil , Grotz, Travis E. , Smoot, Rory L. , Truty, Mark J. , Kendrick, Michael L. , Nagorney, David M. , Grotz, Travis E , Truty, Mark, Cleary, Sean, Kendrick, Michael, Nagorney, David, Navin, Patrick, Thiels, Cornelius A , Smoot, Rory L , Gudmundsdottir, Hallbera , Takahashi, Hiroaki , Starlinger, Patrick , Warner, Susanne G. , Cleary, Sean P. , Navin, Patrick J. , Hálfdánarson, Þorvarður R. , Thiels, Cornelius A.

Journal of Surgical Oncology | August 2, 2023 | Volume: 128 | Issue: 7 | Pages: 1072-1079

10.1002/jso.27413 Get It

AbstractBackground and ObjectivesWe assessed the accuracy of preoperative gallium‐68 DOTA‐Tyr3‐octreotate (DOTATATE) positron emission tomography (PET) imaging in estimating multifocality and nodal metastases of small bowel neuroendocrine tumors (sbNETs).MethodsA multicenter analysis was performed on patients with sbNETs who underwent preoperative DOTATATE PET imaging and surgical resection, with manual palpation of the entire length of the small bowel, between January 2016 and August 2022. Preoperative imaging reports and blinded secondary imaging reviews were compared to the final postoperative pathology reports. Descriptive statistics were applied.ResultsOne‐hundred and four patients met inclusion criteria. Pathology showed 53 (51%) patients had multifocal sbNETs and 96 (92%) had nodal metastases. The original preoperative DOTATATE PET imaging identified multifocal sbNET in 28 (27%) patients and lymph node (LN) metastases in 80 (77%) patients. Based on original radiology reports, sensitivity for multifocal sbNET identification was 45%, specificity was 92%, positive predictive value (PPV) was 86%, and negative predictive value (NPV) was 62%. For the identification of LN metastases, sensitivity was 82%, specificity was 88%, PPV was 99%, and NPV was 29%.ConclusionsAlthough DOTATATE PET imaging is specific and relatively accurate, sensitivity and NPV are insufficient to guide surgical planning. Preoperative use should not replace open palpation to identify additional synchronous lesions or to omit regional lymphadenectomy.