Table 1 Characteristics of the patients and US according to the BRAF mutation status.

Age

  Mean ± SD (y)

47.4 ± 13.8 (20–84)

42.4 ± 12.3 (10–67)

0.009

  <50/≥50 y

199 (52.5)/180 (47.5)

40 (67.8)/19 (32.2)

0.028

Gender

  Male/female

91 (24)/288 (76)

9 (15.3)/50 (84.7)

0.136

Size on US

  Mean ± SD (mm)

11.8 ± 8.6 (3–84)

11.3 ± 8.4 (3–44)

0.674

  ≤10/>10 mm

219 (57.8)/160 (42.2)

37 (62.7)/22 (37.3)

0.475

Location

  Upper/middle/low/mixed

40 (37.2)/83 (21.9)/27 (7.1)/229 (60.4)

3 (5.1)/15 (25.4)/3 (5.1)/38 (64.4)

0.516

Nodule number

  Single/multiple

136 (35.9)/243 (64.1)

18 (30.5)/41 (69.5)

0.421

Nodule distribution

  Unilateral/bilateral

173 (45.6)/206 (54.4)

27 (45.8)/32 (54.2)

0.987

Capsule contact

  Yes/no

128 (33.8)/251 (66.2)

16 (27.1)/43 (72.9)

0.311

Capsule involvement

  Yes/no

27 (7.1)/352 (92.9)

5 (8.5)/54 (91.5)

0.919

Echogenicity

  Hypo-/iso- or hypergenicity

357 (94.2)/22 (5.8)

53 (89.8)/6 (10.2)

0.323

Internal component

  Solid/cystic-solid

363 (95.8)/16 (4.2)

53 (89.8)/6 (10.2)

0.104

Shape

  Regular/irregular

154 (40.6)/225 (59.4)

19 (32.2)/40 (67.8)

0.218

Margin

  Ill-defined/well-defined

164 (43.3)/215 (56.7)

28 (47.5)/31 (52.5)

0.547

Calcification

  Micro-/macro-/no calcification

210 (55.4)/22 (5.8)/147 (38.8)

42 (71.2)/4 (6.8)/13 (22)

0.045

Ratio of height and width

  Taller than wide/wider than tall

105 (27.7)/274 (72.3)

18 (30.5)/41 (69.5)

0.656

Vascularity

  Absent/slight/rich

135 (35.6)/231 (60.9)/13 (3.4)

21 (35.6)/37 (62.7)/1 (1.7)

0.776

Blood flow distribution

  Absent/internal/peripheral/mixed

135 (35.6)/138 (36.4)/24 (6.3)/82 (21.6)

21 (35.6)/22 (37.3)/4 (6.8)/12 (20.3)

0.996