Thyroid Nodule Malignancy Rates Within a Health-Care Region with Centralized Pathology

Introduction: The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) characterizes thyroid fine-needle aspiration cytology (FNAC) into 1 of 6 diagnostic categories, each with a corresponding rate of malignancy (ROM) that may be influenced by factors such as the nodule risk stratification pathway, technical and cytopathology experience, statistical method used to calculate malignancy rates and duration of follow up. The aim of this study was to establish the local ROM for TBSRTC categories in order to guide clinical decision making in Southern Alberta.