Malignancy rate in thyroid nodules categorized as atypia of undetermined significance or follicular lesion of undetermined significance - An institutional experience.

Introduction: Atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS) of Bethesda system for reporting thyroid cytopathology has emerged as most controversial category due to its heterogeneity and inconsistent usage. Initially associated risk of malignancy was estimated to be about 5-15%, but eventually different results have been obtained across institutions due to variable follow-ups and interpretation. The present study was conducted to evaluate the rate of malignancy along with appropriate management in this category.