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Gudmundsdottir, Hallbera

0000-0002-1297-2769

Mayo Clinic

No affiliation available

Citations 7

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.
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.
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.
Finding the Balance Between Reduced Opioid Prescribing and Patient-reported Pain Management Among General Surgery Patients
Gudmundsdottir, Hallbera , Ubl, Daniel S. , Yost, Kathleen J. , Gazelka, Halena M. , Gudmundsdottir, Hallbera , Habermann, Elizabeth B. , Thiels, Cornelius A.

Annals of Surgery | August 22, 2022 | Volume: 278 | Issue: 2 | Pages: 208-215

10.1097/sla.0000000000005680 Get It

Objective: To compare patient-reported outcomes before and after implementation of evidence-based, procedure-specific opioid prescribing guidelines. Background: The opioid epidemic remains a significant public health issue. Many institutions have responded by reducing opioid prescribing after surgery. However, the impact of this on patient-reported outcomes remains poorly understood. Methods: Opioid-naïve adults undergoing 12 elective general surgery procedures at a single institution prospectively completed telephone surveys at median 26 days from discharge. Patients were compared before (March 2017–January 2018) and after (May 2019–November 2019) implementation of evidence-based, procedure-specific opioid prescribing guidelines. Results: A total of 603 preguideline and 138 postguideline patients met inclusion criteria and completed surveys. Overall, 60.5% of preguideline and 92.5% of postguideline prescriptions fell within recommendations (P<0.001), while refill rates were similar (4.5% vs 5.8%, P=0.50). A statistically significant drop in median morphine milligram equivalent prescribed was observed for 9 of 12 procedures (75%). No opioids were prescribed for 16.7% of patients in both cohorts (P=0.98). While 93.3% of preguideline and 87.7% of postguideline patients were very/somewhat satisfied with their pain control, the proportion of patients who were very/somewhat dissatisfied increased from 4.2% to 9.4% (P=0.039). Conclusions: Prescribing guidelines successfully reduced opioid prescribing without increased refill rates. Despite decreased prescribing overall, there was a continued reluctance to prescribe no opioids after surgery. Although most patients experienced good pain control, there remains a subset of patients whose pain is not optimally managed in the era of reduced opioid prescribing.
Survival and Incidence Patterns of Pancreatic Neuroendocrine Tumors Over the Last 2 Decades: A SEER Database Analysis
Sonbol, Mohamad Bassam , Mazza, Gina L. , Mi, Lanyu , Oliver, Thomas , Starr, Jason S. , Gudmundsdottir, Hallbera , Hobday, Timothy J. , Hobday, Timothy, Sonbol, Mohamad B , Mazza, Gina L , Gudmundsdottir, Hallbera , Oliver, Thomas, Cleary, Sean P. , Hálfdánarson, Þorvarður R.

The Oncologist | February 18, 2022 | Volume: 27 | Issue: 7 | Pages: 573-578

10.1093/oncolo/oyac049 Get It

Abstract Background Pancreatic neuroendocrine tumors (pNETs) are rare cancers with outcomes determined by multiple factors including grade, stage, and clinical presentation. In this study, we aimed to determine the prognosis of patients with pNETs using a large population-based database. Materials and Methods In this population-based study, we identified patients with pNETs from the SEER 18 registry (2000-2016) using a combination of ICD-O-3 and histology codes. We calculated age-adjusted incidence rates using SEER*Stat 8.3.5. In addition, we analyzed overall survival (OS) using the Kaplan-Meier method, and investigated prognostic factors using a multivariable Cox proportional hazards model. Results A total of 8944 pNETs patients were identified. Annual incidence rates increased from 0.27 to 1.00 per 100 000. This was largely explained by an increase in number of patients diagnosed with localized disease in more recent years (2012-2016). Median OS was 68 months (95% CI [64, 73]) and 5-year OS rates in localized, regional, and metastatic disease were 83%, 67%, and 28%, respectively. There was a significant improvement in OS for patients diagnosed between 2009 and 2016 (median OS 85 months) compared with those diagnosed between 2000 and 2008 (median OS 46 months) (HR 0.66; 95% CI [0.62, 0.70]). This improvement in OS was consistent across all stages. Conclusions and Relevance This study shows a steady increase pNETs incidence with notable stage migration to earlier stages in recent years. This increase in incidence is accompanied by a significant improvement in survival across different disease stages.
Multifocality is not associated with worse survival in sporadic pancreatic neuroendocrine tumors
Gudmundsdottir, Hallbera , Graham, Rondell P. , Sonbol, Mohamad Bassam , Smoot, Rory L. , Truty, Mark J. , Kendrick, Michael L. , Nagorney, David M. , Habermann, Elizabeth B. , Hálfdánarson, Þorvarður R. , Sonbol, Mohamad B , Cleary, Sean P. , Smoot, Rory L , Habermann, Elizabeth , Graham, Rondell P , Halfdanarson, Thorvardur R , Gudmundsdottir, Hallbera

Journal of Surgical Oncology | July 26, 2021 | Volume: 124 | Issue: 7 | Pages: 1077-1084

10.1002/jso.26618 Get It

Abstract Background and Objectives Pancreatic neuroendocrine tumors (pNETs) in patients with hereditary cancer syndromes are typically multifocal. In contrast, sporadic pNETs are usually unifocal and the incidence of multifocal sporadic pNETs is unknown. The primary aim of this study was to investigate the incidence of multifocality in sporadic pNETs and any associated effect on recurrence risk and survival. Methods Patients who underwent resection of pNETs at Mayo Clinic from 2000 to 2019 were identified and clinical data were obtained from medical records. Syndromic disease was defined as pNETs arising in the setting of a hereditary cancer syndrome. Statistical comparisons were made using χ 2 , Fisher's exact, and Kruskal–Wallis tests and survival was assessed using the Kaplan–Meier method. Results Six hundred and sixty‐one patients with sporadic pNETs and fifty‐nine with syndromic pNETs were identified. Multifocal disease was present in 4.8% of sporadic patients and 84.7% of syndromic patients ( p < .001). Within patients with sporadic pNETs, clinicopathologic features and recurrence‐free and overall survival were similar between patients with unifocal and multifocal disease. Conclusions Multifocal sporadic pNETs are rare and multifocality is not associated with worse survival or increased recurrence risk. Patients with multifocal sporadic pNETs can likely be safely managed with a combination of resection and observation as indicated for each tumor.