Diagnostic and Therapeutic Approach to Thyroid Nodules

Thyroid nodules are highly prevalent in the adult population, particularly when detected by high-resolution ultrasound, yet only a minority represent clinically significant malignancy. Contemporary management has shifted from routine biopsy or surgery toward a risk-adapted strategy aimed at identifying nodules with meaningful malignant potential, autonomous function, compressive symptoms, or cosmetic impact while avoiding overdiagnosis and overtreatment. Initial evaluation should include clinical history, physical examination, serum thyroid-stimulating hormone, and high-quality neck ultrasonography. Radionuclide scintigraphy is indicated when thyroid-stimulating hormone is suppressed to identify hyperfunctioning nodules, which are rarely malignant and are usually managed according to thyroid functional status. Ultrasound-based risk stratification systems guide the need for fine-needle aspiration according to sonographic pattern and size thresholds. Fine-needle aspiration with Bethesda cytology remains the cornerstone of preoperative diagnosis, although indeterminate cytology continues to represent a major challenge. Molecular testing can refine malignancy risk in selected indeterminate nodules but remains limited by cost, access, local cancer prevalence, and variable impact on patient-centered outcomes. Most benign asymptomatic nodules require observation rather than intervention. Surgery is reserved for malignant, suspicious, symptomatic, compressive, or selected indeterminate nodules. Minimally invasive treatments, including ethanol ablation and thermal ablation, are increasingly used for selected benign symptomatic nodules. This review summarizes the diagnostic pathway, cytologic interpretation, therapeutic options, follow-up strategies, and emerging technologies in thyroid nodule management.