Retrospective Cohort Study
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Sep 6, 2025; 13(25): 105204
Published online Sep 6, 2025. doi: 10.12998/wjcc.v13.i25.105204
Risk factors and outcomes of metastatic poorly differentiated thyroid carcinoma
Chih-Wei Hsu, Chuen Hsueh, Yu-Ling Lu, Chia-Jung Hsu, Richard J Wong, Shu-Fu Lin
Chih-Wei Hsu, Chia-Jung Hsu, Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan
Chuen Hsueh, Department of Pathology, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
Yu-Ling Lu, Shu-Fu Lin, Department of Internal Medicine, New Taipei Municipal TuCheng Hospital, New Taipei City 236, Taiwan
Richard J Wong, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY 10065, United States
Author contributions: Lin SF contributed to study conception; Hsu CW and Lin SF contributed to study design; Hsu CW, Hsueh C, Lu YL, and Hsu CJ contributed to data acquisition and analysis; all authors contributed to data interpretation; Hsu CW, Wong RJ, and Lin SF contributed to manuscript writing; all authors reviewed and revised the manuscript.
Supported by New Taipei Municipal TuCheng Hospital (Built and Operated by Chang Gung Medical Foundation), New Taipei City, Taiwan, No. CORPVVP0031; and the National Science and Technology Council of Taiwan, No. NSTC 112-2314-B-182A-111-MY3.
Institutional review board statement: This study was approved by the Ethics Committee on Research of the Institutional Review Board at Chang Gung Memorial Hospital (No. 202401356B0) and was conducted in accordance with the principles of the Declaration of Helsinki.
Informed consent statement: Informed consent was waived by the Institutional Review Board at Chang Gung Memorial Hospital.
Conflict-of-interest statement: All authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
STROBE statement: Authors have read the STROBE Statement checklist of items, and the manuscript was prepared and revised according to the STROBE Statement checklist of items.
Data sharing statement: The original contributions presented in the study are included in the article and Supplementary materials. Further inquiries can be directed to the corresponding author.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Shu-Fu Lin, MD, Department of Internal Medicine, New Taipei Municipal TuCheng Hospital, No. 2 Jingcheng Road, New Taipei City 236, Taiwan. mmg@cgmh.org.tw
Received: January 15, 2025
Revised: March 31, 2025
Accepted: May 18, 2025
Published online: September 6, 2025
Processing time: 173 Days and 22.6 Hours
Abstract
BACKGROUND

Poorly differentiated thyroid carcinoma (PDTC) is a rare and aggressive form of thyroid cancer. Distant metastasis occurs frequently in PDTC.

AIM

To determine factors associated with distant metastasis and the effects of metastasis, either diagnosed on initial presentation or developing during follow-up, on mortality in PDTC patients.

METHODS

Patients with PDTC diagnosed between January 1, 1985 and July 31, 2022 were identified using a thyroid cancer database at a medical center in Taiwan. Factors associated with distant metastasis and cancer-specific survival (CSS) were analyzed using binary logistic analysis and Cox regression, respectively. Survival analysis was conducted using the Kaplan–Meier method.

RESULTS

The study cohort included 39 patients with PDTC, including 16 with distant metastasis on initial presentation, 5 with metastasis during the follow-up period, and 18 with no evidence of metastasis. Older age (≥ 45 years) was significantly associated with a higher risk of distant metastasis (odds ratio: 5.31; 95% confidence interval: 1.27–22.2; P = 0.018), while sex, tumor size, T stage, and N stage were not associated with distant metastasis. Patients with metastatic PDTC, either diagnosed at presentation or developing during follow-up, had poorer 5-year CSS rates (55.0% and 40.0%, respectively) than those without metastasis (5-year CSS, 93.8%) (P = 0.001 for both comparisons).

CONCLUSION

Older patients with PDTC have an increased risk of distant metastasis. Patients with metastatic PDTC, both diagnosed at presentation and developing during follow-up, have a dismal prognosis.

Keywords: Poorly differentiated thyroid carcinoma; Age; Lymph node metastasis; Distant metastasis; Survival

Core Tip: Poorly differentiated thyroid carcinoma (PDTC) is a rare but aggressive subtype of thyroid cancer. A significant proportion of patients with PDTC have distant metastasis. Patients with metastatic PDTC diagnosed at presentation or developing during follow-up have dismal 5-year cancer-specific survival rates of only 55.0% and 40.0%, respectively. Older age (≥ 45 years) is a risk factor for metastatic PDTC.