Ipsilateral Central Neck Dissection Plus Frozen Section Examination Versus Prophylactic Bilateral Central Neck Dissection in cN0 Papillary Thyroid Carcinoma

Background Ipsilateral central compartment node dissection (IpsiCCD) can reduce the morbidity of prophylactic bilateral central compartment node dissection (BilCCD) in papillary thyroid carcinoma (PTC) but it carries the risk of contralateral metastases being overlooked. Frozen section examination (FSE) of removed ipsilateral nodes has been proposed to intraoperatively assess nodal status. We compared IpsiCCD plus FSE and BilCCD in clinically unifocal and node negative PTC. Methods One hundred patients were prospectively assigned to undergo total thyroidectomy (TT) plus BilCCD or TT plus IpsiCCD. In the IpsiCCD group, removed lymph nodes were sent for FSE. If FSE was positive for metastases, a BilCCD was accomplished. Results The two groups included 50 patients each. Overall, occult lymph node metastases were found in 41 patients—20 in the IpsiCCD group and 21 in the BilCCD group. FSE correctly identified occult node metastases in 13 of 20 pN1a patients in the IpsiCCD group (overall accuracy 86 %). Seven node metastases were not detected at FSE—five were micrometastases (≤2 mm). Six of 13 patients in the IpsiCCD group who underwent BilCCD and 6 of 21 BilCCD pN1a patients had bilateral metastases. More patients in the BilCCD group showed transient hypocalcemia (27/50 vs. 18/50, respectively) [p = NS]. No patient experienced recurrent disease. Conclusions FSE of ipsilateral nodes is accurate in determining nodal status, allowing the extension of the central neck clearance to be reliably modulated. Routine IpsiCCD plus FSE of the ipsilateral nodes could be a valid alternative to prophylactic BilCCD since it allows accurate staging and may reduce morbidity.