Table 1.
Accepted Thyroid FNA Classification Schemes
| Suggested Categories | Alternate Category (s) terms* | Risk of Malignancy** |
| Benign | <1% | |
| Follicular lesion of undetermined significance | Atypia of undetermined significance | 5–10% |
| R/O Neoplasm | ||
| Atypical follicular lesion | ||
| Cellular Follicular Lesion | ||
| Follicular Neoplasm | Suspicious for follicular neoplasm | 20–30% |
| Suspicious for Malignancy | 50–75% | |
| Malignant | 100% | |
| Non-diagnostic | Unsatisfactory |
*These terms can be used instead of the suggested category terms (based on website responses and NCI meeting attendees); ** Data collected from literature [71-73, 80, 98]