Table 2.

Clinical and Radiological Features in Patients with Non-Diagnostic Thyroid Nodules^a

Factors	Malignant nodules (n = 15)	Benign nodules (n = 480)	OR [CI]	p
Clinical factors based on 472 patients
Age (years)	49 (39–67)	61 (52.3–70.2)	0.97 [0.94–1]	0.07
Sex (male)	35.7% (5/14)	27.5% (126/458)	0.5 [0.03–3.15]	0.50
Family history of thyroid cancer	16.7% (2/12)	3.4% (14/416)	4.79 [0.7–19.9]	0.52
History of neck radiation	0	7.4% (21/281)		0.19
TSH (mIU/L)	1.4 (0.6–2.3)	1.5 (0.9–2.4)	0.89 [0.39–1.27]	0.69
Ultrasound and pathology factors based on 495 nodules
Initial nodule size (cm)	1.2 (0.8–2.3)	1.95 (1.2–2.9)	0.55 [0.28–0.93]	0.02
Solid nodule	73.3% (11/15)	50.7% (221/436)	2.67 [0.9–9.77]	0.08
Hypoechogenicityb	27.3% (3/11)	33.8% (75/222)	1.81 [0.56–8.0]	0.34
Presence of calcifications	53.3% (8/15)	18.5% (80/432)	5.03 [1.76–14.73]	<0.01
Increased vascularityc	53.3% (8/15)	66.7% (20/30)	1.33 [0.71–1.40]	0.69
Presence of colloid	0 (0/15)	11.3% (54/479)		0.39
Presence of macrophages	26.7% (4/15)	19% (91/479)	1.55 [0.42–4.65]	0.47
Acellular aspirate	6.7% (1/15)	2.5% (12/478)	2.8 [0.15–15.7]	0.40
Bloody aspirate	0 (0/15)	7% (34/479)		0.61

Continuous variables are presented as median with IQR, and categorical variables as percentage (n). Statistically significant values are shown in bold.

^aOnly 472 patients with 495 nodules included in the analysis.

^bEchogenicity was assessed for fully solid nodules.

^cVascularity was assessed in all 15 cancers and 30 controls matched by age and sex at a 1:2 ratio.

OR, odds ratio; CI, confidence interval.