Rethinking Malignancy Risk in Indeterminate Thyroid Nodules with Positive Molecular Studies: Southern California Permanente Experience.

Objectives: To recognize that thyroid nodules with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS; Bethesda III) have different risks of malignancy based on genetic mutation and to consider molecular testing of nodules with AUS/FLUS to help avoid unnecessary morbidity or cost.

Study Design: Retrospective cohort study.

Setting: Multiple locations within Southern California Permanente Medical Group.