J Korean Soc Radiol.  2016 Aug;75(2):126-132. 10.3348/jksr.2016.75.2.126.

Characteristic Sonographic and Follow Up Features of Thyroid Nodules According to Childhood Age Groups

• Nam BD
• Chang YW
• Hong SS
• Hwang JY
• Lim HK
• Lee JH
• Lee DH

• KMID: 2344802
• DOI: http://doi.org/10.3348/jksr.2016.75.2.126

Abstract

PURPOSE
We analyzed the spectrum and the significance of pediatric thyroid nodules depicted on sonography and evaluated the follow-up change according to the age group.
MATERIALS AND METHODS
We retrospectively reviewed the sonographic features of 82 nodules in 69 patients (6.6%) among 1282 children less than 13 years of age without a palpable lesion, from January 2006 to January 2013. Patients were divided into three age groups; infants, preschoolers, and schoolers. Thyroid nodules were evaluated according to their sonographic characteristics (simple cyst, colloid cyst, solid mass, or intrathyroid thymus) and the changes detected at follow-up (disappearance, decrease in size, no change or increase in size) were reported.
RESULTS
There was a significant difference in the nodule patterns among the age groups (p < 0.001). The nodules in infants included a simple cyst (n = 12), a solid mass (n = 12), or an intra-thyroid thymus (n = 9). The preschoolers had a simple cyst (n = 11), a colloid cyst (n = 5), a solid mass (n = 3) or an intra-thyroid thymus (n = 5). However, the schoolers had a simple cyst (n = 2), a colloid cyst (n = 18), and a solid mass (n = 5), but there was no case of intra-thyroid thymus. Follow-up of 38 cases revealed significant differences among the age groups (p = 0.018). The nodules in infants showed findings such as disappearance of nodules (n = 9) and no change (n = 10) on follow-up sonography. In preschoolers, the nodules had disappeared (n = 2), decreased in size (n = 1), and showed no change (n = 11). However, the nodules in schoolers were found to be decreased in size (n = 1), show no change (n = 2), and increased in size (n = 2). The proven pathologic finding was benign in four patients.
CONCLUSION
There were significant differences in the prevalence and the interval change of thyroid nodules among infants, preschoolers, and schoolers. A large series of intrathyroid thymus was seen in infants and preschoolers, and masses did not increase in size in these age groups. The frequency of a colloid cyst could be increased in schoolers, and masses were increased in size in this age group, but none of the patients showed a malignant finding on pathology.

MeSH Terms

Child
Colloid Cysts
Follow-Up Studies*
Humans
Infant
Pathology
Pediatrics
Prevalence
Retrospective Studies
Thymus Gland
Thyroid Gland*
Thyroid Nodule*
Ultrasonography*

Figure

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  Fig. 1 Intrathyroid thymus is defined as a hypoechoic mass with multiple punctuate echogenic foci (arrow), showing same sonographic appearance as the thymus (T). A. Transverse scan. B. Longitudinal scan.

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  Fig. 2 Multiple colloid cysts are evident in the right lower pole of the thyroid in an 11-year-old girl with a clinical history of tonsillitis.

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  Fig. 3 Longitudinal sonogram of thyroid gland shows target-like lesions with an echogenic center and a hypoechoic peripheral rim (arrow). The lesion was disappeared on follow-up ultrasonography (not included in figure).

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  Fig. 4 A. There is circumscribed, oval, hypoechoic solid mass in the right upper pole of the thyroid gland in an 8-year-old boy. B. The mass is increased in size (1.43 mL to 3.00 mL) at the 5-year follow-up examination. The patient underwent a core needle biopsy of the mass. The histological diagnosis was Hurthle cell adenoma.

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