SAT-330 Thioredoxin and Tetraspanin 30 (CD63) as Potential Biomarkers for Angioinvasion in Papillary Thyroid Cancer: Screening and Prognostic Implications

Abstract Disclosure: A. Buczynska: None. M. Kościuszko: None. A. Popławska-Kita: None. A. Kretowski: None. Papillary thyroid cancer (PTC) is the most common thyroid malignancy and is generally associated with a favorable prognosis. However, a subset of patients exhibits a more aggressive disease course, frequently characterized by angioinvasion, which significantly increases the risk of local invasion, recurrence, and distant metastases, ultimately leading to poorer clinical outcomes. The identification of reliable biomarkers for angioinvasion is crucial for improving risk stratification and facilitating more precise clinical decision-making, potentially guiding the implementation of more aggressive therapeutic strategies, such as extended surgical resection and early radioiodine therapy (RAI). Among the emerging biomarkers with potential relevance to tumor progression and angiogenesis, thioredoxin (Thx) and tetraspanin 30 (CD63) have garnered significant interest. Thx, a redox-regulating protein, promotes tumor aggressiveness, immune modulation, and metastasis, while CD63, a tetraspanin family protein, facilitates tumor-endothelial interactions and vascular invasion. As oxidative stress correlates with poorer prognosis in angioinvasive PTC, Thx and CD63 may serve as novel biomarkers for angioinvasion, providing insights into tumor vascular invasion mechanisms. A total of 45 patients with angioinvasive PTC (study group) and 45 patients without angioinvasion and characterized by a very low risk of cancer progression (reference group) after thyroidectomy were included. Serum levels of Thx and CD63 were quantified and analyzed for their association with angioinvasion, followed by an assessment of their screening performance using the area under the curve (AUC) evaluation. Serum Thx and CD63 levels were significantly higher in the angioinvasive group comparing to reference group (both, p<0.001). Logistic regression confirmed a strong association with angioinvasion, supporting their role in tumor angioinvasion. Thx (AUC = 0.85) and CD63 (AUC = 0.83) demonstrated clinical screening significance. Their strong association with angioinvasion, confirmed by logistic regression, highlights their relevance in identifying aggressive PTC subtypes. A combined Thx-CD63 panel further improved angioinvasion screening accuracy (AUC = 0.93). Further studies are needed to validate their clinical utility and explore their role in personalized treatment. Presentation: Saturday, July 12, 2025