‘Indeterminate for malignancy’ (Tir3/Thy3 in the Italian and British systems for classification) thyroid fine needle aspiration (FNA) cytology reporting: morphological criteria and clinical impact

Abstract

A five-tiered classification, subdividing the 'indeterminate for malignancy' class into 'follicular proliferations' and 'atypical lesions' could be adopted. As a result of their higher risk of malignancy, surgical management of the atypical lesions would be justified. In future, the introduction of a genetic panel might contribute to their stratification, to the determination of a more accurate risk of malignancy of the atypical lesions and to the verification of follicular proliferations that are benign.