Clinicoradiological Predictors of Malignancy in the Atypical Category by the Yokohama System for Reporting Breast Fine-Needle Aspiration Cytopathology.

Introduction: The atypical category (AC) by the Yokohama system is an indeterminate group characterized by predominantly benign cytomorphology of the lesions, with some uncommon features that may be seen in malignancy in breast fine-needle aspiration. The risk of malignancy (ROM) varies from 13% to 25%. Its management depends on the clinical and radiological findings.