Table 1.

TBSRTC: recommended diagnostic categories [4]

Number	Name of the category
I	Nondiagnostic or unsatisfactory
	Cystic fluid only
	Virtually acellular specimen
	Other (obscuring blood, collecting artifacts, etc.)
II	Benign
	Consistent with a benign follicular nodule (includes adenomatoid nodule, colloid nodule etc.)
	Consistent with lymphocytic (Hashimoto) thyroiditis in the proper clinical context
	Consistent with granulomatous (subacute) thyroiditis
	Other
III	Atypia of undetermined significance or follicular lesion of undetermined significance
IV	Follicular neoplasm or suspicious for a follicular neoplasm
	Specify if Hurthle cell (oncocytic type)
V	Suspicious for malignancy
	Suspicious for papillary carcinoma
	Suspicious for medullary carcinoma
	Suspicious for metastatic carcinoma
	Suspicious for lymphoma
	Other
VI	Malignant
	Papillary thyroid carcinoma
	Poorly differentiated carcinoma
	Medullary thyroid carcinoma
	Undifferentiated (anaplastic) carcinoma
	Squamous cell carcinoma
	Carcinoma with mixed features (specify)
	Metastatic carcinoma
	Non-Hodgkin’s lymphoma
	Other