Impact of Ultrasonographic Features Indicative of Malignancy on Tumor Advancement in Thyroid Cancer—A Single-Center Study

Background: Ultrasonography is frequently used preoperatively to assess thyroid nodules. Hypoechogenicity, microcalcifications, high vascularity, or irregular tumor shape suggest malignancy. Methods: This is a retrospective analysis of 724 patients from 2008 to 2024 who underwent surgery for TC. Preoperative data, ultrasonographic findings, and histopathological results were collected. Ultrasonographic features indicative of possible malignancy included hypoechogenicity, microcalcifications, high vascularity, and irregular tumor shape. These were correlated with histopathologically seen extrathyroidal extension, capsular and vascular invasion, and lymph node metastasis. Results: A statistically significant association was seen for each of the evaluated ultrasonographic features (p < 0.05). More advanced TC had a greater number of suspicious ultrasonographic features averaging 3.05 to 3.12. Microcalcifications, high vascularity, and irregular tumor shape showed a strong correlation (r > 0.7) with all histopathological features. Hypoechogenicity had a strong correlation with lymph node metastasis and a moderate correlation (r = 0.5–0.7) with other features. Conclusions: Ultrasonographic features predict the likelihood of histopathological extrathyroidal extension, capsular and vascular invasion, and lymph node metastasis.