Lateral neck multilevel fine‐needle aspiration cytology and thyroglobulin estimation in papillary thyroid carcinoma

Abstract

Objective To assess the accuracy of preoperative ultrasound‐guided multilevel fine‐needle aspiration (FNA) cytology and thyroglobulin (Tg) estimation in mapping metastatic levels in the lateral neck, in patients with papillary thyroid carcinoma (PTC). Methods Patients with PTC clinically metastasizing to the lateral neck who were initially treated at the Peking University Cancer Hospital from June 2018 to September 2020 were included. FNA was performed preoperatively in each suspicious neck level; cytological examination (FNA‐C) and Tg measurement of the needle‐washout fluid (FNA‐Tg) were combined to determine metastasis. FNA‐Tg cutoff value was calculated, and the accuracy of FNA at different levels were evaluated. Results In total, 111 patients underwent 124 lymph node dissections. The best cutoff value of FNA‐Tg for the diagnosis of metastatic level was 1.0 ng/mL. Multilevel FNA showed sensitivity, specificity, positive predictive value, and negative predictive value in predicting single‐level metastasis of 100%, 61.0%, 43.9%, and 100%, respectively. In 64 (51.6%) cases, the involved levels diagnosed by FNA were consistent with that diagnosed by postoperative pathology. Conclusion FNA‐Tg improves the diagnostic performance of FNA‐C in lateral neck lymph node metastases. However, limited accuracy was obtained for preoperative multilevel FNA in predicting the extent of metastasis in the lateral compartment.

Surgeon‐performed fine‐needle aspiration for lymph nodes behind the big cervical vessels in papillary thyroid cancer

“…Despite the small size of retrovascular lymph nodes, US‐guided FNA provided satisfactory adequacy and diagnostic accuracy. According to our recent research, in which all aspirated lymph nodes were resected and analyzed, when FNA cytology was combined with FNA‐Tg, the sensitivity, specificity, PPV, NPV, and accuracy for predicting lateral neck metastasis were 85.6%, 90.1%, 96.4%, 66.7%, and 86.7%, respectively 13 . In another surgeon‐performed US‐guided lymph node FNA study with at least 6 months of follow‐up as the standard of benign lymph node, the sensitivity and specificity in diagnosing nodal metastasis were 92% and 89%, respectively 9 .…”

“…Before FNA, radiologists performed a neck ultrasound on all patients, assessing the central and lateral neck compartments for possible metastasis and recording the results. The criteria for prompting biopsy included: the maximum diameter ≥ 0.5 cm, hyperechogenicity, cystic changes, unbalanced inner echo, calcification, or a roughly round shape (long/transverse diameter ratio < 1.5) 11–13 . Retrovascular lymph node was defined as the entire or most of the targeted lymph node between the medial margin of the common carotid artery and the lateral margin of the internal jugular vein.…”

“…All the operation processes of FNAs were recorded as pictures or videos to confirm their locations and needle paths. As previously reported, a Tg washout concentration of 1 ng/ml was used as the cutoff value 13 . Cytopathologic and Tg test reports were obtained within 1–2 days.…”

“…The criteria for prompting biopsy included: the maximum diameter ≥ 0.5 cm, hyperechogenicity, cystic changes, unbalanced inner echo, calcification, or a roughly round shape (long/transverse diameter ratio < 1.5). [11][12][13] Retrovascular lymph node was defined as the entire or most of the targeted lymph node between the medial margin of the common carotid artery and the lateral margin of the internal jugular vein. Computed tomography (CT) was not routinely performed before FNA, but it was recommended before subsequent neck dissection if the FNA result was positive.…”

“…As previously reported, a Tg washout concentration of 1 ng/ml was used as the cutoff value. 13 Cytopathologic and Tg test reports were obtained within 1-2 days. The data was used to finalize the surgical strategy.…”