Ultrasound Risk Categories for Thyroid Nodules and Cytology Results: A Single Institution’s Experience after the Adoption of the 2016 Update of Medical Guidelines by the American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi

Table 3

Distribution of cytologic results according to the ultrasound risk categories of nodules evaluated by fine needle aspiration.

	TIR1	TIR2	TIR3A	TIR3B	TIR4	TIR5
Low risk; (341)	29	276	33	3	0	0	TIR2 versus others < 0.01
	(8.5%)	(80.9%)	(9.7%)	(0.9%)	(0%)	(0%)
Intermediate risk; (489)	51	328	93	11	4	2	TIR2 versus others < 0.01
	(10.4%)	(67.1%)	(19%)	(2.3)	(0.8%)	(0.4%)
High risk; (29)	3	1	3	5	2	15	TIR5 versus others < 0.01
	(10.3%)	(3.5%)	(10.3%)	(17.3%)	(6.9%)	(51.7%)
	NS	Low versus intermediate risk = NS	Low versus intermediate risk < 0.01	Low versus intermediate risk = NS	Low versus intermediate risk = NS	Low versus intermediate risk = NS
		Low versus high risk < 0.01	Low versus high risk = NS	Low versus high risk < 0.01	Low versus high risk < 0.01	Low versus high risk < 0.01
		Intermediate versus high risk < 0.01	Intermediate versus high risk = NS	Intermediate versus high risk < 0.01	Intermediate versus high risk < 0.05	Intermediate versus high risk < 0.01