Thyroid Nodules Located in the Lower Pole Have a Higher Risk of Malignancy than Located in the Isthmus: A Single-Center Experience

Table 3

Evaluation of FNAB results according to ultrasonographic features.

Variables	FNAB
	Benign (n = 633)	Malignant (n = 24)
Ecogenicity
Isoechoic	324 (51.2)^a	1 (4.2)^b	<0.001
Hypoechoic	226 (35.7)^a	22 (91.7)^b
Hyperechoic	31 (4.9)^a	0 (0.0)^a
Mixed echoic	52 (8.2)^a	1 (4.2)^a
US findings
Cystic areas	175 (49.9)^a	1 (4.2)^b	<0.001
Necrosis	21 (6.0)^a	2 (8.3)^a
Microcalcification	117 (33.3)^a	10 (41.7)^a
Macrocalcification	14 (4.0)^a	0 (0.0)^a
Border irregularity	8 (2.3)^a	8 (33.3)^b
Intermittent wall calcification	10 (2.8)^a	0 (0.0)^a
Taller than wide	6 (1.7)^a	3 (12.5)^b
Doppler US
No blood flow	71 (12.0)^a	6 (26.1)^b	<0.001
Peripheral blood flow	325 (54.7)^a	3 (13.0)^b
Central blood flow	40 (6.7)^a	8 (34.8)^b
Central and peripheral blood flow	158 (26.6)^a	6 (26.1)^a

Data expressed as n (%). Similar letters on the same line indicate similarity between groups and different letters indicate differences between groups. US: ultrasonography.