Despite FNAB being the critical diagnostic test for thyroid nodules, decisions regarding the extent of thyroid surgery are also influenced by many other clinical factors. With regards to individual BSRTC diagnostic categories, the false negative rate in the benign category was low, and only marginally higher than the expected BSRTC ROM. The false negatives in this group were due to a follicular carcinoma case and a single follicular variant of PTC case. With respect to the AUS/FLUS diagnostic group, five of 17 (29.4%) cancer cases were diagnosed as follicular variant of PTC. In the malignant diagnostic group, 58/59 cases (98%) were malignant by final histopathological assessment. The single case within this group that had a benign pathological diagnosis was described as a ‘follicular adenoma with cytological atypia’ and this diagnosis was confirmed by an external pathology review. Despite the overlap in observations made across several studies, there has been the suggestion that the risk of malignancy in the AUS/FLUS category may be institution-specific due to variability in its utilization and application by cytopathologists . As the majority of thyroid lesions do not undergo an operation, there is really no consistent way to confirm whether or not many of the FNAB diagnoses were actually accurate. This is also true for the recently described benign pathological diagnosis: non-invasive follicular tumor with PTC-like nuclear features (NIFTP). Though reclassifying some of our malignant cases into the NIFTP category would decrease the ROM across all BSRTC groups, NIFTP is a histopathological diagnosis, and would not assist with cytology-based preoperative decision making. However, given efforts to clearly define NIFTP diagnostic criteria, along with its utilization in clinical practice, it is probable that the overall risks of malignancy across all BSRTC categories will decrease. Furthermore, a study limitation arises because some of the cases, especially those with an unsatisfactory, benign or AUS/FLUS BSRTC diagnosis may only be followed clinically, and because they did not undergo an operation, they are not included in our study population. In real-world practice, patient characteristics such as a history of prior neck radiation exposure, or a familial thyroid cancer history, influence the decision to operate and the extent of surgery, and this information is usually not available to reporting cytopathologists. Certainly, study of these variables, in combination with the BSRTC diagnosis, could potentially further augment cancer ROM estimation, and influence treatment.