Thyroid Dysfunction After Intensity-Modulated Radiotherapy and PD⁃1 Inhibitor Treatment for Locally Advanced Nasopharyngeal Carcinoma

Kai Shang; Qianyong He; Xinyu Xu; Xunyan Luo; Chaofen Zhao; Lina Liu; Zhuoling Li; Yuanyuan Li; Feng Jin

doi:10.2147/TCRM.S489899

Thyroid Dysfunction After Intensity-Modulated Radiotherapy and PD⁃1 Inhibitor Treatment for Locally Advanced Nasopharyngeal Carcinoma

Ther Clin Risk Manag. 2025 Jan 6:21:15-25. doi: 10.2147/TCRM.S489899. eCollection 2025.

Authors

Kai Shang^#^{1

2}, Qianyong He^#^{1

2

3}, Xinyu Xu², Xunyan Luo², Chaofen Zhao^{1

3}, Lina Liu^{1

2

3}, Zhuoling Li^{1

2

3}, Yuanyuan Li^{1

2

3}, Feng Jin^{1

3}

Affiliations

¹ Department of Oncology, the Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.
² School of Clinical Medicine, Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.
³ Department of Oncology, the Affiliated Cancer Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.

^# Contributed equally.

Abstract

Purpose: Analyze the incidence and risk factors of thyroid dysfunction in patients with advanced nasopharyngeal carcinoma (LA-NPC) after intensity-modulated radiotherapy (IMRT) and PD⁃1 inhibitor treatment and their relationship with treatment efficacy and prognosis.

Methods: Eighty-five LA-NPC patients treated with IMRT and PD-1 inhibitors were retrospectively collected from March 1, 2019, to May 30, 2022. The incidence of thyroid dysfunction after combination therapy was analyzed. The Kaplan-Meier method was used to analyze the relationship between thyroid dysfunction and patient prognosis. Logistic regression analysis was used to screen independent risk factors for thyroid dysfunction.

Results: As of data cutoff (May 31, 2024), the median follow-up time was 27.8 months (range: 25.6 to 32.0 months). The median time of onset of thyroid dysfunction was 8.26 months. The incidence of thyroid dysfunction is 47.06% (40/85), with clinical hypothyroidism being the main cause at an incidence rate of 28.24% (24/85) and clinical hyperthyroidism at an incidence rate of 3.53% (3/85). The incidence of grade 1 thyroid immune-related adverse events (irAEs) was 29.41% (25/85), and the incidence of grade 2 thyroid irAEs was 17.65% (15/85). Patients with thyroid dysfunction had longer overall survival, progression-free survival, and distant metastasis-free survival at both one and two years compared to patients with normal thyroid function, but the difference was not statistically significant (p > 0.05). Multivariate logistic regression analysis showed that pretreatment lactate dehydrogenase (LDH) (p = 0.079) is an independent predictor of thyroid dysfunction after radiotherapy in combination with immunotherapy for LA-NPC.

Conclusion: The study found that the addition of immunotherapy increases the risk and shortens the onset time of thyroid dysfunction in LA-NPC patients treated with chemoradiotherapy. Pretreatment LDH may serve as an independent risk factor for thyroid dysfunction for LA-NPC patients.

Keywords: IMRT; PD-1 inhibitor; nasopharyngeal carcinoma; survival; thyroid dysfunction.

Grants and funding

This research was supported in part by grants from the Guizhou Provincial Science and Technology Projects (grant numbers Qiankehe Fundamentals ZK [2024] General 189 and Qianke Synthetic Fruit LC [2023] 029), the Guizhou Medical University Affiliated Hospital Doctoral Research Initiation Fund Project (grant number gyfybskj-2022-07), the Guizhou Medical University Affiliated Hospital 2023 National Natural Science Foundation Cultivation Project (grant number gyfynsfc-2023-39), and the National Natural Science Foundation of China (grant number 82060556).