High-Score US-Suspicious Subcentimeter Thyroid Nodules: What Factors Affect Adequate Sampling of US-Guided Fine-Needle Aspiration Biopsy?
Table 2
Adequate sample rate in relation to nodule-related factors.
Variable
No. of adequate sampling cases
Total no. of cases
Adequate sample rate (%)
P value
Nodule size (mm)
0.007
3–6
80
110
72.7
7–10
203
239
84.9
Nodule location
0.916
Right
141
172
82.0
Isthmus
8
10
80
Left
134
167
80.2
Composition
0.312
Solid
269
329
81.8
Mixed
14
20
70
Shape
0.244
Ovoid to round
84
110
76.4
Taller than wide
56
65
86.2
Irregular
143
174
82.2
Margin
0.589
Defined
100
121
82.6
Ill-defined
183
228
80.3
Echogenicity
0.705
Hypoechoic
248
304
81.6
Isoechoic
25
33
75.8
Hyperechoic
10
12
83.3
Calcification
＜0.001
None
96
106
90.6
Microcalcification
148
182
81.3
Macrocalcification
39
61
63.9
aA statistically significant difference in diagnostic yield between nodules without calcification and nodules with either microcalcification () or macrocalcification () and nodules with microcalcification and macrocalcification ().
