Effect of Hashimoto’s Thyroiditis on Efficacy of <sup>131</sup>I Ablation Therapy in Intermediate- and High-Risk of Thyroid Papillary Carcinoma

Abstract

Objective: The purpose of this study was to investigate the effect of Hashimoto’s thyroiditis on efficacy of 131I ablation in intermediate- and high-risk of thyroid papillary carcinoma patients. The findings will help to develop a personalized treatment plan for patients with thyroid papillary carcinoma complicated with Hashimoto’s thyroiditis. Material and Methods: From January 2016 to December 2020, patients who were diagnosed with intermediate- and high-risk PTC with lymph node metastasis were analyzed retrospectively, excluding patients with incomplete clinical data, distant metastasis, positive TGAb, TSH 131I on patients outcome. Results: A total of 525 patients (166 males and 359 females) were included in the study, including 368 patients in ER group (70.1%) and 157 patients in NER group (29.9%). Eleven factors including combining Hashimoto’s thyroiditis, pre-ablative Tg levels, sex, tumor diameter, extraglandular invasion, multifocal, bilateral lesions, central lymph node metastasis, lateral lymph node metastasis, lymph node metastasis rate, thyroglobulin were statistically different between ER group and NER group with significance at P 131I treatment in intermediate- and high-risk thyroid papillary carcinoma. Hashimoto’s thyroiditis, high Ps-Tg level and increased number of lateral lymph node metastasis reduce the efficacy of 131I therapy in patients with intermediate and high risk thyroid papillary carcinoma.