Imaging-Detected Incidental Thyroid Nodules that Undergo Surgery: A Single-Center Experience Over 1 Year

American Journal of Neuroradiology

Table 1:

Characteristics of benign and malignant ITNs that undergo surgery

	Benign ITN	Malignant ITN	All ITN	P Value
Age^{^a}	58 ± 14	54 ± 13	56 ± 14	.3
Sex
Female	16 (67)	19 (83)	35 (74)	.3^{^b}
Male	8 (33)	4 (17)	12 (26)
Nodule size (in mm)
Imaging^{^a}	22 ± 13	17 ± 7	20 ± 11	.2
Pathology	NA	14 ± 8	NA
Imaging modality on which ITN was detected				.2^{^b,^c}
CT	9 (38)	13 (57)	22 (47)
PET/CT	4 (17)	6 (26)	10 (21)
Ultrasound	7 (29)	2 (9)	9 (19)
MRI	3 (13)	1 (4)	4 (9)
Chest radiograph	1 (4)	0	1 (2)
Echocardiogram	0	1 (4)	1 (2)
Cytology				<.001^{^b,^d}
I—Nondiagnostic or unsatisfactory	2 (8)	1 (4)	3 (6)
II—Benign	2 (8)	0	2 (4)
III—Atypia of undetermined significance/follicular lesion of undetermined significance	10 (42)	1 (4)	11 (23)
IV—Follicular neoplasm/suspicious for follicular neoplasm	8 (33)	1 (4)	9 (19)
V—Suspicious for malignancy	2 (8)	6 (26)	8 (17)
VI—Malignant	0	14 (61)	14 (30)
Total	24	23	47

Note:—Unless otherwise specified, data are numbers of patients, with percentages in parentheses. Percentages may not add up to 100% due to rounding.
↵a Data reported as mean ± standard deviation.
↵b Calculated with Fisher exact test.
↵c For CT versus other imaging modalities.
↵d For diagnostic categories I, II, and II versus IV, V, and VI.

Table 2:

The Duke 3-tiered system for CT, MRI, or PET-detected thyroid nodules

Category	Criteria for Categories	Recommendations
Risk category 1: Highly suspicious for malignancy	PET avid thyroid nodule	Strongly consider work-up with ultrasound for any size nodule
	Suspicious lymphadenopathy^{^a}
	Extrathyroid spread with or without signs of vocal cord palsy on side of nodule
	Lung metastases
Risk category 2: Indeterminate with risk factor of young age	Age <35 years	Consider work-up with ultrasound if ≥1 cm in adults
	Age <35 years	Consider work-up with ultrasound for any size in pediatric patients
Risk category 3: Indeterminate without risk factors	Age ≥35 years	Consider work-up with ultrasound if ≥1.5 cm

Note:—Intended for management of incidental thyroid nodules in low-risk patients.
↵a Suspicious lymph nodes are defined as nodes >10 mm in short axis (with the exception of jugulodigastric lymph nodes, which were permitted to be up to 15 mm in short axis), or nodes that contained either calcifications, cystic components, or irregular margins.