Coexistence of Histologically Confirmed Hashimoto's Thyroiditis with Different Stages of Papillary Thyroid Carcinoma in a Consecutive Chinese Cohort.

Xiaoyun Liu,Lijun Zhu,Erik K Alexander,Meiping Shen,Yunsong Wu,Zhixiao Wang,Huanhuan Chen,Zhihong Zhang,Xiaodong Wang,Yu Duan,Dai Cui,Tao Yang,Jiawei Chen,Rong Rong

doi:10.1155/2014/769294

Abstract

Purpose. To determine the relationship between Hashimoto's thyroiditis (HT) and all stages of papillary thyroid carcinoma (PTC) with or without local lymph node metastasis (LNM). Methods. We conducted a retrospective study of thyroidectomies from 2008–2013 in First Affiliated Hospital of Nanjing Medical University. We categorized patients according to the presence of histopathologically proven HT. The prevalence of mPTC (maximum diameter ≤ 10 mm) and crPTC (clinical relevant PTC) and local LNM rates were compared. Results. We evaluated 6,432 consecutive thyroidectomies. In total, 1,328 specimens were confirmed as HT. The prevalence of PTC in this HT cohort was 43.8%, significantly higher than non-HT group. After adjustment of gender and age, the prevalence of PTC was still higher in HT group. HT was a risk factor for PTC in multivariate analysis with odds ratio 2.725 (95% CI, 2.390–3.109) (P < 0.001). However, no correlation was found between HT and LNM of PTC. Conclusion. HT was associated with an increased prevalence of all stages of PTC, independent of tumor size, gender, and age. In contrast, locally advanced disease defined by LNM was unrelated to HT. These data suggest an association of HT with low risk PTC and a potential protective immunologic effect from further disease progression.

Highlights

Thyroid cancer is the most common endocrine malignancy worldwide, with a significant increase in global incidence [1,2,3,4] over the past decade
To elucidate the uncertainty as to the influence of Hashimoto’s thyroiditis (HT) upon local tumor growth, we conducted a retrospective study trying to clarify the relationship between HT and different stages of papillary thyroid carcinoma (PTC)
Thyroidectomies were performed for the following reasons: (a) worrisome findings from ultrasonography and/or abnormal lymph node enlargement, (b) malignancy suspected from previous thyroid FNA, or inconclusive FNA results, (c) patients with multiple or bilateral nodules or symptoms of neck or throat compression, or enlargement during follow-up, and (d) concerning clinical or physical examination findings warranting consideration for removal

Summary

Introduction

Thyroid cancer is the most common endocrine malignancy worldwide, with a significant increase in global incidence [1,2,3,4] over the past decade. Hashimoto’s thyroiditis (HT) has been postulated to have a causative relationship to PTC, being suggested as a possible risk factor for developing PTC. This link was first proposed in 1955 with several subsequent retrospective studies showing similar results [11,12,13,14,15]. Occult or microscopic PTC (mPTC) is frequently incidentally detected in histologic samples even when benign nodules are assumed It is uncertain whether incidental micro-PTC (mPTC) represents an early stage of overt (or clinically relevant) PTC or is a different subtype of PTC which seldom progresses. To elucidate the uncertainty as to the influence of HT upon local tumor growth (even from a very early stage), we conducted a retrospective study trying to clarify the relationship between HT and different stages of PTC

Methods

Results

Discussion

Conflict of Interests