The Underestimated Impact of Hashimoto Thyroiditis on Thyroid Papillary Carcinoma

It is stated that Hashimoto's Thyroiditis (HT) is a risk factor for the development of Papillary Thyroid Cancer (PTC). However, the effect of HT on the coexistence of HT and PTC is still controversial. In this study, our aim is to investigate the effect of the presence of HT on clinicopathological data in patients with PTC. All 356 patients whose pathology was reported as PTC who were operated between 2015 and 2023 were included in the study. PTC patients were divided into 2 groups as those with and without HT. The effect of HT association on clinicopathological features was investigated. In 356 PTC patients, the rate of HT was 31.2%. PTC patients with HT had less multifocality (p < 0.05), more lymph node metastases (LNM) (p < 0.01) compared to PTC patients without HT. The presence of HT did not affect the bilaterality of the tumor, tumor diameter, lymphovascular invasion, or capsule invasion. While multifocality was observed less frequently in PTC patients with HT, lymph node metastasis rates were higher.