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Updated: Jan 31, 2026

Computer-Aided Three-Dimensional Visualization in the Treatment of Locally Advanced Thyroid Cancer
Published on: June 9, 2023
Adjuvant external beam radiotherapy for locally invasive papillary thyroid cancer
Uchechukwu C Megwalu1, Lisa A Orloff1, Yifei Ma1
1Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, California.
Background:
The goal of this study was to assess the impact of adjuvant external beam radiotherapy (EBRT) on survival in patients with locally invasive papillary thyroid carcinoma.
Methods:
Propensity score analysis was performed on 870 patients with surgically resected T4 papillary thyroid carcinoma, identified in the Surveillance, Epidemiology, and End Results Database between 1988 and 2013.
Results:
EBRT was associated with worse overall survival (OS) (HR 1.60, 95% CI 1.18-2.16) and disease-specific survival (DSS) (HR 1.58, 1.09-2.30). Subset analysis of patients with major extrathyroidal invasion showed that EBRT was associated with worse OS (HR 1.53, 95% CI 1.04-2.25), but not with DSS (HR 1.57, 95% CI 0.99-2.50).
Conclusion:
Adjuvant EBRT, in the initial management of locally invasive papillary thyroid cancer, was not associated with a survival benefit. Future studies are needed to determine which subset of patients may benefit from adjuvant EBRT.
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