Abstract

Objective

In the management of the pediatric thyroid nodules with atypia of undetermined significance (AUS) cytology, The American Thyroid Association (ATA) pediatric guidelines recommend surgery while The European Thyroid Association (ETA) guidelines recommend fine-needle aspiration biopsy (FNAB) repetition after 6 months. The aim of this study is to determine the markers of malignancy in AUS cases and to discuss the management of pediatric AUS nodules.

Methods

The specimens of the 20 patients who underwent surgery due to AUS cytology were re-evaluated and subcategorized according to the Bethesda 2023 classification. 

Results

On the histological diagnosis of the cases, 11 (55%) were benign; while 9 were malignant (45%). On the subcategorization of AUS, nuclear atypia was present in 14 patients (70%), other atypia in 6 patients (30%). Of the cases with nuclear atypia, 64.3% were malignant (n=9) while no malignancy was detected in the cases with other atypia (p=0.012). Among the cytopathological features, chromatin clearing, nuclear enlargement, and irregular margins were significantly associated with malignancy (p=0.035, p=0.003, p=0.012, respectively).   Adhering to ETA recommendations would delay diagnosis by at least 6 months in 45% of our malignant cases. Conversely, performing lobectomy according to ATA recommendations may lead to unnecessary surgery in 55% of our cases.

Conclusion

Based on the data from our study, lobectomy appears to be a more appropriate approach in AUS cases only with nuclear atypia to avoid diagnostic leap and unnecessary surgery. Guidelines should be updated according to the latest Bethesda.