• US - TC - FNA - Thyroid nodules ≥4 cm - FU

Thyroid nodules constitute a prevalent clinical concern, affecting about half of the population as revealed by neck imaging. The apprehension surrounding thyroid nodules arises from the potential risk of thyroid cancer, with approximately 5-8% of these nodules being associated with malignancy. Neck ultrasound (US) and fine needle aspiration (FNA) represent the major diagnostic tools that physicians use to evaluate the potential risk of malignancy. Current diagnostic guidelines for thyroid cancer endorse the use of FNAB to assess the risk of malignancy. This assessment is founded on a combination of sonographic patterns and the size of the thyroid nodule. The ease of performing US-guided FNAB, coupled with its high sensitivity and specificity exceeding 90%, renders it the most dependable diagnostic method for identifying malignancies in thyroid nodules. This approach boasts a low false-negative rate and minimal complications. Apart from the biopsy findings, the decision to recommend thyroidectomy for a patient is frequently influenced by the size of the nodule. Several research investigations have indicated an elevated risk of malignancy and a higher false-negative rate during FNAB for nodules that are ≥4 cm in size. Certain authors propose a recommendation for the surgical excision of nodules ≥4 cm, irrespective of the cytology results. Conversely, opinions from other sources assert that such intervention may not be imperative. We aimed to conduct a single centre retrospective study on 126 nodules managed trough periodical US and FNAB in our centre in Pisa undergone to surgery (mostly due development of compression-related symptoms and/or cytological results suggestive of malignancy), reporting nodules-associated features (US findings and modifications), age, gender, thyroid function at surgery and patient-related illnesses or clinical conditions such as presence of autoimmune diseases, family history of thyroid carcinoma (first and second degree family members), exposition to radiations and smoke habit. Moreover for every nodule was reported the date of diagnosis and the date of surgery, finding a significant time-reduction between malignant and benign nodules. This finding in our opinion shows how FNAB and US may be effective to early detect thyroid cancer, even in bigger nodules. Furthermore, the number of cytologically benign FNA before surgery and the result of FNA at surgery was investigated, finding also in this case a time-reduction between benign nodules and the malignant cases.
Consequently, the study suggests that the decision to perform resection solely based on the size of thyroid nodules exceeding 4 cm is not warranted to rule out malignancy and US-guided FNA may be reliable in the early detection of thyroid tumour clinically relevant, even in nodules greater than 4 cm.