Risk for malignancy of thyroid nodules: Comparative study between TIRADS and US based classification system

Abstract

Purpose: To compare between TIRADS and thyroid ultrasound classification system proposed by Kim and his colleagues. Methods and materials: Prospective analysis of ultrasound and power Duplex images of 450 patients with thyroid gland disease was conducted. The thyroid lesions were categorized into 5 groups: TIRADS 1, Normal thyroid gland; TIRADS 2, benign in aspects; TIRADS 3, probably benign aspects; TIRADS 4A, low suspicious aspects; TIRADS 4B & TIRADS 5, high suspicious aspects. Next, the detected nodules in 350 patients were divided into solid and partially cystic nodules and rated according to Kim et al., classification. The final diagnosis was done by biopsy (n = 370) and clinical follow-up (n = 80). Statistical analysis in comparison with cytopathological findings was calculated. Results: The odds ratio (OR) was 7 for TIRADS 5, 2 for TIRADS 4B, 0.67 for TIRADS 4A, 0.2 for TIRADS 3 and 0.01 for TIRADS 1 & 2. The PPV of malignancy rises gradually from 0% for TIRADS 1 & 2 to 6.7% for TIRADS 3 & 4A to 20% for TIRADS 4B and reaches 67% for TIRADS 5. TIRADS 5 showed 100% sensitivity, 86% specificity and 89% accuracy. Conclusion: TIRADS classification is reliable, easier and simpler than other classification system for reporting. It has higher sensitivity for prediction of thyroid malignancy.

Keywords

• Ultrasound
• Thyroid
• Tumor
• Malignant
• Benign
• TIRADS