Benign thyroid nodules classified as ACR TI-RADS 4 or 5: Imaging and histological features

Jiamin Chen; Dalin Ye; Shuhui Lv; Xuefeng Li; Feile Ye; Yongquan Huang; Zhongzhen Su; Yuhong Lin; Ting Xie; Xin Wen

doi:10.1016/j.ejrad.2023.111261

Benign thyroid nodules classified as ACR TI-RADS 4 or 5: Imaging and histological features

Eur J Radiol. 2023 Dec 14:175:111261. doi: 10.1016/j.ejrad.2023.111261. Online ahead of print.

Authors

Jiamin Chen¹, Dalin Ye², Shuhui Lv², Xuefeng Li², Feile Ye², Yongquan Huang³, Zhongzhen Su⁴, Yuhong Lin⁵, Ting Xie⁶, Xin Wen⁷

Affiliations

¹ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: chenjm268@mail2.sysu.edu.cn.
² The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China.
³ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: huangyq39@sysu.edu.cn.
⁴ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: suzhzh3@mail.sysu.edu.cn.
⁵ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: Linyh97@mail.sysu.edu.cn.
⁶ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: xieting@mail.sysu.edu.cn.
⁷ The Fifth Affiliated Hospital Sun Yat-Sen University, Zhuhai 519000, China. Electronic address: wenxin7@mali.sysu.edu.cn.

PMID: 38493559
DOI: 10.1016/j.ejrad.2023.111261

Abstract

Background: American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) being most widely applied in clinical practice, there is an overlap in US imaging manifestations between benign and malignant thyroid nodules.

Objectives: To analyze the imaging and histological characteristics of pathological benign thyroid nodules categorized as American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) 4 or 5, and to explore the correlation between the suspicious sonographic signs resulting in the misdiagnoses and the histopathological features.

Materials and methods: Overall, 227 benign thyroid nodules (215 patients) in ACR TI-RADS 4 or 5 sampled through surgical excision were analyzed between December 2020 and August 2022. We retrospectively reread the ultrasound (US) images of the pathological discordant cases, after which we performed a systematic analysis focusing on the histopathological characteristics of thyroid lesions and recorded the findings. Qualitative US features and pathological significance of the thyroid nodules were analyzed using the chi-square and Fisher's exact tests.

Results: The pathological type of 227 thyroid nodules (n = 103 in ACR TI-RADS 4 and n = 124 in ACR TI-RADS 5) was nodular goiter together with other histopathological features, namely, fibrosis (n = 103, 45.4 %), calcification (n = 70, 30.8 %), adenomatous hyperplasia (n = 31, 13.7 %), follicular epithelial hyperplasia (n = 23, 10.1 %), Hashimoto's thyroiditis (n = 18, 7.9 %), and cystic degeneration (n = 16, 7.1 %). Fibrosis was the most common histopathological feature in both ACR TI-RADS 4 (n = 42, 40.8 %) and 5 (n = 61, 49.2 %) categories of benign thyroid nodules. Thyroid nodules with fibrosis demonstrated sonographic features of "taller than wide" (p < 0.05), while lesions with follicular epithelial hyperplasia were likely to be detected with irregular and/or lobulated margins and very hypoechoic on US (p < 0.05 for both).

Conclusion: Benign thyroid nodules with histopathological findings such as fibrosis are associated with suspicious US features, which may give inappropriately higher TIRADS stratification.

Keywords: ACR TI-RADS; Benign thyroid nodule; False-positive; Histopathology; Sonographic imaging.