Endocrine Abstracts

Background: There are two types of thyroid nodule biopsy: fine-needle aspiration (FNAB) and core-needle (CNB). Multiple studies mainly from Eastern Asia demonstrate safety and efficacy of CNB, however it is very rarely used in Europe.

Methods: Retrospective analysis of the first 281 CNBs performed in Romania, including 8 lymph nodes and 3 thyroid bed lesions. We used the Korean Thyroid Association reporting system (KTA-CNB) for histology reports.

Results: Of 281 CNBs, there were only 3 non-diagnostic results (1.1%), 21 category III results (7.5%) and 22 category IV results (7.8%). Categories IIIa and IVa were almost exclusively benign (n=17, of them 6 underwent surgery, 5 were confirmed benign, 1 NIFTP). Out of 7 patients with category IVc results, 6 underwent surgery, 4 of them had malignant results postoperatively. All category V (n=5) and VI (n=18) results were confirmed to be malignant on postoperative histology. Two of thyroid bed lesions were malignant, one benign (all confirmed on postoperative histology). One of 8 lymph nodes was malignant. There was one case of Hurthle cell carcinoma diagnosed preoperatively based on invasion observed at one of the passes, and one case of the lung adenocarcinoma metastasis diagnosed based on IHC. There were 2 cases of papillary microcarcinoma with confirmed extrathyroidal extension which lead to more curative surgical approach, and patients could avoid second surgery or radioiodine therapy. We performed on average 2.2 passes per lesion. There were no major complications, some minor adverse events were limited to bruising, perithyroidal hematoma and pain during or after procedure. Two patients had intrathyroidal hematoma.

Conclusion: The CNB is a safe and reliable diagnostic procedure for thyroid nodules, thyroid bed lesions and cervical lymph nodes. It offers very low chance of non-diagnostic results, lower chance of inconclusive results with a better stratification of risk between different subcategories (III a-d, IV a-c), among them the highest chance of malignancy was observed in category IVc in our study. CNB is a procedure which improves patient experience by reducing the number of procedures needed to make a clinical decision. It also offers possibility to use IHC and observe extrathyroidal extension.