Abstract: Objective To analyze the clinicopathologic features of Hashimotos thyroiditis(HT)complicated with papillary thyroid cancer(PTC). Methods A total of 297 patients with PTC treated surgically during Oct. 2013 and Oct. 2015 were divided into 2 groups: experimental group(PTC complicated with HT, n=49, 5 males and 44 females, aged 24-67 years, 27 cases < 45 years), and control group(PTC only, n=248, 60 males and 188 females, aged 17-76 years, 97 cases < 45 years). The clinical data of the 2 groups were compared and analyzed statistically, including gender, age, diffusely enlarged thyroid gland, level of serum autoimmune antibody, capsular invasion, tumor size, intraoperative frozen pathology, and TNM staging. Results There were statistically significant differences between the 2 groups in gender, age, diffusely enlarged thyroid gland, level of serum autoimmune antibody and central lymph node metastasis(all P<0.05), but no statistical differences in capsular invasion, tumor size, intraoperative frozen pathology and TNM staging(all P>0.05). Conclusion HT complicated with PTC is more common in female patients, especially young women. It usually manifests as diffusely enlarged thyroid, increased serum autoimmune antibody and early lymph node metastasis. HT patients should check regularly for timely diagnosis and treatment.

Key words: Hashimotos thyroiditis, Papillary thyroid cancer, Pathologic features