Endocrine Abstracts

Background and Objective: In thyroid cancer (TC) central compartment (CC) neck dissection (CCND) should accompany thyroidectomy in case of clinical and/or cytological suspicion of lymph node (LN) metastases. Cervical ultrasound has been indicated as the first-line examination in the pre-operative staging of TC, although its diagnostic performance in evaluating CC LN is controversial. Proving that cervical ultrasound can accurately identify CC metastases would allow to use this exam to choose surgery extension, avoiding prophylactic CCND and its higher surgical risks. Aim of this study was to evaluate sensitivity (SS), specificity (SP) and diagnostic accuracy (DA) of preoperative cervical ultrasound in detecting CC LN metastases in TC patients referred to a high-volume center for thyroid diseases.

Methods: We enrolled patients undergoing total thyroidectomy and at least unilateral CCND for TC at our center between January 2010 and July 2022; we included only those for whom a preoperative cervical ultrasound aimed at the study of cervical LN was available. Histological examination was considered as the gold standard. The location in which staging ultrasound was performed (our center vs other centers) and the size of primary tumor were taken into consideration as variables potentially impacting study outcomes.

Results: 198 patients were included. Most of them had preoperative ultrasound performed at our center (86%) and had a small tumor (57% T1, 14% T2, 28% T3). On preoperative ultrasound, CC LN were defined as suspicious for metastases in 45% of cases. On definitive histological examination nodal metastases were found in 55.5% of patients. SS, SP and DA of preoperative ultrasound were respectively 60.9%, 75% and 67.2%. SS and DA were higher in the group of patients who had preoperative ultrasound performed at our center (respectively 73% and 73.1%; P < 0.001); SS and DA were inversely correlated with primary tumor size, although this was not statistically significant (Table 1).

Conclusions: Preoperative cervical ultrasound presents some limitations in the correct local staging of TC patients, especially in the evaluation of CC lymphatic involvement. Our data highlight that, given the better SS and DA, it should be preferably performed in high-volume centers specifically dedicated to thyroid diseases; however, especially in case of larger primary tumors, prophylactic CCND should be taken in consideration.