Coexistence of Hashimoto's thyroiditis with papillary thyroid carcinoma: The influence of lymph node metastasis

Background The aim of this study was to evaluate the influence of coexistent Hashimoto's thyroiditis with papillary thyroid carcinoma on lymph node metastasis. Methods The coexistent Hashimoto's thyroiditis group was defined by the presence of thyroid autoantibodies or pathologic confirmation. The control group did not have autoantibodies, disease, or ultrasound findings of Hashimoto's thyroiditis. Results For the Hashimoto's thyroiditis group, only central lymph node metastasis had a lower frequency and the mean number of central metastatic lymph nodes was lower than in the control group after adjustment. With regard to lateral lymph node involvement, there was no significant difference between the 2 groups. The multivariate analysis showed a negative association between the coexistence of Hashimoto's thyroiditis and central lymph node metastasis. Conclusions Coexisting Hashimoto's thyroiditis in patients with papillary thyroid carcinoma was identified as a negative independent predictive factor for central lymph node metastasis. © 2010 Wiley Periodicals, Inc. Head Neck, 2010