HALF OF THE PATIENTS WITH CLINICALLY UNIFOCAL T1B/SMALL T2 NODE NEGATIVE PAPILLARY THYROID CARCINOMA SCHEDULED FOR THYROID LOBECTOMY MAY REQUIRE COMPLETION THYROIDECTOMY IF THE NODAL STATUS IS EVALUATED

AUTHORS:
A. Laurino (Rome, Italy) , F. Pennestrì (Rome, Italy) , A. Martullo (Rome, Italy) , P. Gallucci (Rome, Italy) , F. Prioli (Rome, Italy) , L. Sessa (Rome, Italy) , E.D. Rossi (Rome, Italy) , C. De Crea (Rome, Italy) , M. Raffaelli (Rome, Italy)
Background:
Thyroid lobectomy (TL) should be preferred over total thyroidectomy (TT) for small unifocal, papillary thyroid carcinoma (PTC), in the absence of aggressive features. Despite prophylactic central neck dissection is not usually recommended, occult, non-microscopic (>2 mm), nodal metastases (ONM) may occur in clinically node-negative (cN0) PTC, increasing the risk of recurrence.
Methods:
Among 4216 patients operated for thyroid malignancies (January 2014-Nomber 2023), 110 (2.6%) with unifocal cT1b/small cT2 (<3 cm) cN0 PTCs were scheduled for TL plus ipsilateral central neck dissection (I-CND). Completion thyroidectomy (CT) was accomplished during the same procedure when frozen section examination (FSE) of removed nodes showed ONM and within 6 months in case of aggressive pathologic features at final pathology.
Results:
There were 102 (92.7%) cT1b and 8 (7.3%) cT2 PTC. FSE was positive for ONM in 33 (30%) cases, requiring immediate CT. Median number of removed and metastatic nodes at definitive pathology were 12 and 5, respectively. Multifocality was present in 25 (75.7%) cases, angioinvasion in 25 (75.7%), aggressive variants in 9 (27.3%) and extracapsular extension in 1 (3.0%). Among the remaining 77 patients, 24 (31.2%) were subsequently scheduled for CT, due to ONM/aggressive histopathological features. Overall, 57 (51.8%) patients underwent immediate or delayed CT.
Conclusions:
Half of unifocal cT1b/small cT2 (1-3 cm) cN0 PTC scheduled for TL required CT because of ONM/aggressive features. I-CND and FSE evaluation of the removed nodes allow to intraoperatively modulate the extension of resection, ensuring accurate staging and reducing the risk of recurrence and the need for reoperation.