Table 1. Comparison of reporting systems for thyroid fine-needle aspiration cytology.
| Papanicolaou Society of Cytopathology (in 1997) | Japanese Society of Thyroid Surgery (in 2005) | Bethesda system (in 2007, 2017) | Japan Thyroid Association (in 2013) | Japanese Society of Thyroid Surgery (in 2015); Japanese Association of Endocrine Surgery and The Japanese Society of Thyroid Pathology (in 2019) |
|---|---|---|---|---|
| Unsatisfactory for interpretation | Inadequate | Non-diagnostic or unsatisfactory* | Inadequate | Unsatisfactory |
| Benign non-neoplastic lesions* | Normal or benign* | (II) Benign | Normal or benign* | Cyst fluid |
| Cellular follicular lesions | Benign | |||
| Follicular neoplasm | Intermediate | (III) Atypia of undetermined significance or follicular lesion of undetermined significance | Indeterminate B (other tumors) |
Undetermined significance |
| Favor benign | ||||
| Favor malignant | ||||
| Hürthle cell neoplasm | (IV) Follicular neoplasm or suspicious for a follicular neoplasm | Indeterminate A (follicular neoplasm) | Follicular neoplasm | |
| A-1: favor benign | ||||
| A-2: borderline | ||||
| A-3: favor malignant | ||||
| Suspicious for malignancy | Malignancy suspected | (V) Suspicious for malignancy | Suspicious for malignancy | Suspicious for malignancy |
| Malignant | Malignant | (VI) Malignant | Malignant | Malignant |
*, including cyst fluid.