Investigating the clinical significance of immune and thyroid biomarkers in women with breast cancer and Hashimoto's thyroiditis.

Breast cancer with Hashimoto's thyroiditis (BC-HT) presents a unique immuno-thyroid interplay that remains poorly understood. This study investigates the relationships between thyroid function markers (TSH, T3, T4), immune markers (CD33, CD44), and thyroid autoantibodies (Anti-TPO, Anti-Tg) in BC-HT patients and healthy controls. Normality testing confirmed non-parametric data distribution, necessitating Mann-Whitney U tests for group comparisons. BC-HT patients exhibited significantly elevated TSH, CD33, Anti-TPO, and Anti-Tg levels, alongside reduced T3 and T4, compared to controls, indicating thyroid dysfunction. Spearman's correlation analysis revealed strong negative correlations between TSH and T3/T4 in controls, which were lost in BC-HT, suggesting disruption of normal thyroid feedback mechanisms. Additionally, CD33 and CD44 correlations with thyroid hormones were evident in controls but absent in BC-HT, highlighting altered immune-thyroid interactions. ROC analysis demonstrated high diagnostic performance for TSH, Anti-Tg, and Anti-TPO, with sensitivities exceeding 0.75, whereas CD33 and CD44 showed limited diagnostic utility. These findings suggest a distinct immuno-thyroid dysregulation in BC-HT patients and highlight the potential of thyroid-specific markers for disease stratification. Future research should focus on longitudinal studies and mechanistic investigations to further delineate the role of immune markers in breast cancer pathophysiology within the context of thyroid autoimmunity.