Table 5.
Non-diagnostic thyroid FNA
| Country | Criteria for non-diagnostic FNA | Incidence of non-diagnostic FNA |
|---|---|---|
| China | TBSRTC | 3.6% at one institution |
| India | TBSRTC | 7.4% (0.5%-25.7%) from 38 studies |
| Different criteria in a study: 10 clusters are needed with each having more than 20 cells; in case of presence of tissue fragments, minimum number of fragments required is 8. | ||
| Royal College of Pathologists guidelines in one study | ||
| Japan | General Rules for the Description of Thyroid Cancer system | 10% according to the Japanese system |
| Japanese system | ||
| Korea | TBSRTC | 12.4% (0%-32.6%) from 12 institutions |
| Philippines | TBRSTC | 1.3% and 23.1% from 2 studies |
| Taiwan | Variable but different from TBRSTCa | 8% at one institution |
| Thailand | TBSRTC | 12.7%-47.6% from three institutions |
FNA, fine-needle aspiration; TBSRTC, the Bethesda System for Reporting Thyroid Cytopathology.
a
Most Taiwan pathologists consider that the specimen is negative, but not non-diagnostic when there are less than six groups but more than 50 follicular cells in total or a degenerative hemorrhagic cyst with scant benign follicular cells.