1Department of Surgery, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
2Department of Radiology, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
3Department of Pathology, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
4Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Conflicts of interest
No potential conflict of interest relevant to this article was reported.
Author contributions
Conceptualization: HYP, WHK, HJK, JYP; Data curation: WWK, JHJ, JYP; Formal analysis: WWK, HYP; Methodology: JL; Investigation: WHK, HJK, JYP; Resources: HYP; Software: JYP; Supervision: HYP; Validation: WHK, HJK, JYP; Project administration: WHK; Visualization: RPT; Writing-original draft: WWK; Writing-review & editing: WWK, JHJ, RPT.