Hashimoto's Thyroiditis Minimizes Lymph Node Metastasis in BRAF Mutant Papillary Thyroid Carcinomas

Area of Science:

• Endocrinology
• Oncology
• Pathology

Background:

• Hashimoto's thyroiditis (HT) is an autoimmune condition leading to hypothyroidism.
• HT presents a complex relationship with papillary thyroid cancer (PTC), potentially increasing risk but also influencing progression.
• BRAF mutations in PTC correlate with aggressive disease and poorer outcomes.

Purpose of the Study:

• To investigate the impact of HT on lymph node metastasis (LNM) in patients with BRAF-mutant PTC.
• To determine if HT modifies the aggressive characteristics associated with BRAF mutations in PTC.

Main Methods:

• Retrospective analysis of 427 adult PTC patients diagnosed between 2008 and January 2021.
• Comparison of LNM rates between patients with and without underlying HT, with a focus on BRAF-mutant tumors.
• Statistical analysis to identify independent predictors of LNM.

Main Results:

• Patients with HT showed higher rates of microcarcinoma and less lateral LNM.
• BRAF-mutant PTCs in patients with HT exhibited significantly reduced overall, central, and lateral LNM compared to those without HT.
• HT was identified as an independent protective factor against overall and lateral LNM.

Conclusions:

• Hashimoto's thyroiditis can neutralize the adverse effects of BRAF mutations in PTC.
• HT serves as an independent protective factor against lymph node metastasis in PTC.
• Findings may inform treatment decisions for endocrinologists, oncologists, and surgeons regarding PTC management.