A meta-analysis of Hashimoto's thyroiditis and papillary thyroid carcinoma risk

Objective: It remains inconclusive whether Hashimoto's thyroiditis (HT) predisposes patients to the development of papillary thyroid carcinoma (PTC). We conducted a meta-analysis of the available data to address this question. Results: Twenty-seven eligible studies were selected, including 18 archival thyroidectomy studies, 6 fine-needle aspiration (FNA) studies, and 3 selective FNA or thyroidectomy studies. A total of 76,281 patients, including 12,476 cases of thyroid cancer, were included in these studies. The mean rate of PTC among patients with HT ranged from 1.12% (selective FNA or thyroidectomy studies) to 40.11% (thyroidectomy studies). All three types of studies supported the correlation between HT and PTC. The overall pooled odds ratio (OR) of the PTC risk for HT (HT versus non-HT) was 2.12 (95% confidence interval [CI]: 1.78-2.52). Methods: We searched all relevant published studies using the citation databases PubMed and Embase. The ORs and corresponding 95% CIs were calculated by the random-effects model for the association between HT and PTC. Conclusions: Our meta-analysis confirmed that HT predisposed patients to the development of PTC.