Thorvardur Halfdanarson

Prof. Thorvardur Halfdanarson

Division of Medical Oncology, Mayo Clinic, Rochester, MN 55902, USA
orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2019 in JAMA Oncology
Verified
Journal Article
Closed access
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YWYucai Wang
Yucai Wang
SZShouhao Zhou
Shouhao Zhou
FYFang Yang
Fang Yang
XQXinyue Qi
Xinyue Qi
XWXin Wang
Xin Wang
MWMichael L. Wang
Michael L. Wang
Importance Programmed cell death (PD-1) and programmed cell death ligand 1 (PD-L1) inhibitors have been increasingly used in cancer therapy. Understanding the treatment-related adverse events of these drugs is critical for clinical practice. Objective To evaluate the incidences of treatment-related adverse events of PD-1 and PD-L1 inhibitors and the differences between different drugs and cancer types. Data Sources PubMed, Web of Science, Embase, and Scopus were searched from October 1, 2017, through December 15, 2018. Study Selection Published clinical trials on single-agent PD-1 and PD-L1 inhibitors with tabulated data on treatment-related adverse events were included. Data Extraction and Synthesis Trial name, phase, cancer type, PD-1 and PD-L1 inhibitor used, dose escalation, dosing schedule, number of patients, number of all adverse events, and criteria for adverse event reporting data were extracted from each included study, and bayesian multilevel regression models were applied for data analysis. Main Outcomes and Measures Incidences of treatment-related adverse events and differences between different drugs and cancer types. Results This systematic review and meta-analysis included 125 clinical trials involving 20 128 patients; 12 277 (66.0%) of 18 610 patients from 106 studies developed at least 1 adverse event of any grade (severity), and 2627 (14.0%) of 18 715 patients from 110 studies developed at least 1 adverse event of grade 3 or higher severity. The most common all-grade adverse events were fatigue (18.26%; 95% CI, 16.49%-20.11%), pruritus (10.61%; 95% CI, 9.46%-11.83%), and diarrhea (9.47%; 95% CI, 8.43%-10.58%). The most common grade 3 or higher adverse events were fatigue (0.89%; 95% CI, 0.69%-1.14%), anemia (0.78%; 95% CI, 0.59%-1.02%), and aspartate aminotransferase increase (0.75%; 95% CI, 0.56%-0.99%). Hypothyroidism (6.07%; 95% CI, 5.35%-6.85%) and hyperthyroidism (2.82%; 95% CI, 2.40%-3.29%) were the most frequent all-grade endocrine immune-related adverse events. Nivolumab was associated with higher mean incidences of all-grade adverse events compared with pembrolizumab (odds ratio [OR], 1.28; 95% CI, 0.97-1.79) and grade 3 or higher adverse events (OR, 1.30; 95% CI, 0.89-2.00). PD-1 inhibitors were associated with a higher mean incidence of grade 3 or higher adverse events compared with PD-L1 inhibitors (OR, 1.58; 95% CI, 1.00-2.54). Conclusions and Relevance Different PD-1 and PD-L1 inhibitors appear to have varying treatment-related adverse events; a comprehensive summary of the incidences of treatment-related adverse events in clinical trials provides an important guide for clinicians.

30 May 2008 in Annals of Oncology
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Journal Article
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Thorvardur HalfdanarsonThorvardur Halfdanarson
Thorvardur Halfdanarson
KRK. G. Rabe
K. G. Rabe
JRJ. Rubin
J. Rubin
GPG. M. Petersen
G. M. Petersen
Background: Pancreatic neuroendocrine tumors (PNETs) are uncommon neoplasms that can present with symptoms of hormone overproduction. We evaluated the incidence, prognosis, and temporal trends of PNETs. Patients and methods: We analyzed all cases of PNETs registered in the Surveillance, Epidemiology, and End Results database from 1973 to 2000. Age-adjusted incidence and survival rates were calculated and survival trends over time were evaluated. Results: We identified 1483 cases of PNETs. The crude annual incidence per 1 000 000 was 1.8 in females and 2.6 in males and increased with advancing age. The incidence increased over the study period. Most patients (90.8%) had nonfunctional tumors. Advanced stage, higher grade, and age were the strongest predictors of worse survival. Patients with functional tumors had better outcomes than patients with nonfunctional tumors in both univariate and multivariate analysis (P = 0.004). Survival time increased over the period from 1973 to 2000. No differences were seen in the distribution of stage or age at diagnosis among time periods. Conclusion: PNETs are uncommon neoplasms but the incidence may be increasing. Age, grade, stage, and functional status predict survival in patients with PNETs. Survival has improved over time, but this is not explained by earlier diagnosis or stage migration.

1 January 2020 in Pancreas
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Journal Article
Closed access
JHJames R Howe
James R Howe
NMNipun B. Merchant
Nipun B. Merchant
CCClaudius Conrad
Claudius Conrad
XKXavier M. Keutgen
Xavier M. Keutgen
JHJulie Md Hallet
Julie Md Hallet
RPRodney F. Pommier
Rodney F. Pommier
This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the surgical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The group reviewed a series of questions of specific interest to surgeons taking care of patients with pancreatic neuroendocrine tumors, and for each, the available literature was reviewed. What follows are these reviews for each question followed by recommendations of the panel.

1 June 2008 in Endocrine-Related Cancer
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Journal Article
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Thorvardur HalfdanarsonThorvardur Halfdanarson
Thorvardur Halfdanarson
JRJ. Rubin
J. Rubin
MFM. B Farnell
M. B Farnell
CGC. S Grant
C. S Grant
GPG. M Petersen
G. M Petersen
Pancreatic endocrine tumors (PETs) are uncommon tumors with an annual incidence <1 per 100 000 person-years in the general population. The PETs that produce hormones resulting in symptoms are designated as functional. The majority of PETs are non-functional. Of the functional tumors, insulinomas are the most common, followed by gastrinomas. The clinical course of patients with PETs is variable and depends on the extent of the disease and the treatment rendered. Patients with completely resected tumors generally have a good prognosis, and aggressive surgical therapy in patients with advanced disease may also prolong survival. The epidemiology, prognosis, and established and novel prognostic markers of PETs are reviewed.

11 June 2018 in Journal of the National Comprehensive Cancer Network
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Journal Article
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MSManisha H. Shah
Manisha H. Shah
WGWhitney Goldner
Whitney Goldner
Thorvardur HalfdanarsonThorvardur Halfdanarson
Thorvardur Halfdanarson
EBEmily Bergsland
Emily Bergsland
JBJordan D. Berlin
Jordan D. Berlin
GZGriselda Zuccarino-Catania
Griselda Zuccarino-Catania
The NCCN Guidelines for Neuroendocrine and Adrenal Tumors provide recommendations for the management of adult patients with neuroendocrine tumors (NETs), adrenal gland tumors, pheochromocytomas, and paragangliomas. Management of NETs relies heavily on the site of the primary NET. These NCCN Guidelines Insights summarize the management options and the 2018 updates to the guidelines for locoregional advanced disease, and/or distant metastasis originating from gastrointestinal tract, bronchopulmonary, and thymus primary NETs.

12 January 2015 in Journal of the National Comprehensive Cancer Network
Verified
Journal Article
Closed access
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MKMatthew H. Kulke
Matthew H. Kulke
MSManisha H. Shah
Manisha H. Shah
ABAl B. Benson
Al B. Benson
EBEmily Bergsland
Emily Bergsland
JBJordan D. Berlin
Jordan D. Berlin
DFDeborah Freedman-Cass
Deborah Freedman-Cass
Neuroendocrine tumors (NETs) comprise a broad family of tumors that may or may not be associated with symptoms attributable to hormonal hypersecretion. The NCCN Clinical Practice Guidelines in Oncology for Neuroendocrine Tumors discuss the diagnosis and management of both sporadic and hereditary NETs. This selection from the guidelines focuses on sporadic NETs of the pancreas, gastrointestinal tract, lung, and thymus. Neuroendocrine tumors (NETs) comprise a broad family of tumors that may or may not be associated with symptoms attributable to hormonal hypersecretion. The NCCN Clinical Practice Guidelines in Oncology for Neuroendocrine Tumors discuss the diagnosis and management of both sporadic and hereditary NETs. This selection from the guidelines focuses on sporadic NETs of the pancreas, gastrointestinal tract, lung, and thymus.