Impact of Viral Hepatitis and Thyroid Autoantibodies on Tumor Aggressiveness in Papillary Thyroid Carcinoma

Background and Purpose: To evaluate the impact of chronic viral hepatitis (HBV, HCV) and thyroid autoimmunity on the clinicopathological aggressiveness of papillary thyroid carcinoma (PTC).Methods: This retrospective study included 521 patients with histologically confirmed PTC. Clinicopathological parameters were compared across subgroups stratified by HBV/HCV serostatus, age, gender, and thyroid autoimmunity. Multivariate binary logistic regression was used to identify independent predictors of tumor aggressiveness.Results: Overall, 12 patients (2.3%) were HBsAg-positive and 4 (0.8%) were Anti-HCV-positive. Viral seropositivity was not associated with worse clinicopathological features. In univariate analyses, age < 55 years correlated with central lymph node metastasis. Anti-TPO and anti-Tg positivity increased the risk of extrathyroidal extension (ETE), with anti-TPO positivity also associated with capsular invasion. However, after adjusting for potential confounders in the multivariate model, none of these variables remained statistically significant as independent risk factors for ETE (all p > 0.05).Conclusion: HBV and HCV seropositivity do not worsen the PTC phenotype. Although younger age and thyroid autoimmunity initially correlated with aggressiveness, neither is an independent predictor. PTC aggressiveness is likely driven by multifactorial variables rather than a single serological marker.