Thyroid nodules are a common clinical finding, with a significant increase in its incidence due to the widespread use of ultrasound (US).1 Although over 90% of these nodules are benign, their identification often results in considerable patient anxiety and stress.2 The American Thyroid Association (ATA) guidelines recommend that the follow-up of a benign nodule (Bethesda System for Reporting Thyroid Cytopathology [BSRTC] category II) should include routine physical examinations and US, for which the frequency is determined by the level of suspicion.3 Yet, these recommendations are based on moderate to low-quality evidence alone. Moreover, while existing studies concur that the majority of benign thyroid nodules remain benign over time, their recommendations for adequate follow-up vary greatly, from none to 5 years, with an interval of once a year to every 5 years.4, 5, 6

Therefore, the optimal management of benign nodules remains challenging to date. Despite the generally favorable prognosis for benign thyroid nodules, concerns about potential malignancy often may lead to extensive follow-up and repeated diagnostic procedures, which may not always be necessary. This may result in a significant burden, on both patients and health systems.

The study aims to evaluate the long-term outcomes outcome of benign nodules, regarding risk of malignancy (ROM) and the necessity of repeat fine needle aspiraiton (FNA) biopsies as part of their management. To our knowledge, our study includes the largest cohort of benign thyroid nodules, as well as the longest follow-up period to date, with a rigorous effort to maintain relevant data on all patients including phone interviews, thus reducing missing pertinent data to a minimum.