Table 1. US Findings and Additional Studies of Thyroid Nodules.
| US Findings | Genetic and Additional Study | |
|---|---|---|
| Benign | ||
| Cyst | Complete cyst | |
| Hyperplastic nodule | Cystic lesion with comet tail artifact | |
| Spongiform cystic nodule | ||
| Intrathyroid thymus | Similar US findings to normal thymus | |
| Malignancy | ||
| Papillary cancer | Suspicious malignant nodule | BRAF |
| Diffusely enlarged gland with numerous microcalcifications | RET/PTC | |
| Diffuse infiltration mimic thyroiditis | ||
| Medullary cancer | Similar to PTC | Calcitonin |
| Follicular cancer | Indeterminate nodule | RAS mutations |
| PAX8/PPARγ rearrangement | ||
| Aneuploidy |
Note.- BRAFV600E mutation = B type raf kinase, PAX8/PPARγ rearrangement = paired box 8-peroxisome proliferator-activated receptor gamma, RAS = rat sarcoma, RET/PTC oncogene = rearranged during transfection/papillary thyroid carcinoma, US = ultrasonography