A Randomized Comparison of Carbon Nanoparticles in Endoscopic Lymph Node Dissection Via the Bilateral Areola Approach for Papillary Thyroid Cancer

We assess the value of carbon nanoparticles (CNP) staining in patients undergoing endoscopic thyroidectomy and central compartment lymph node (CLN) dissection via the bilateral areola approach [endoscopic thyroidectomy via bilateral areola approach (ETBAA)]. Methods: This was a prospective randomized study. Three hundred two consecutive early-stage thyroid cancer patients eligible for ETBAA were recruited at the Division of Thyroid Surgery, China- Japan Union Hospital, Jilin University, China. CLN were mapped and retrieved under the guidance of stained or unstained CNP. The location, detection rates, positive nodes, and number of stained lymph nodes were compared. Results: ETBAA patients were randomly divided into a CNP group (n=152) and a control group (n= 150). In the CNP group, the imaging of lymphatic flow could be observed in 1016 (95.9%) lymph nodes, whereas 43 (4.1%) were unstained. The mean number of stained lymph nodes in each procedure was 6.68 (range, 3 to 12). The total number of dissected lymph nodes was 1059 in the CNP group and 872 in the control group (P=0.00). There was a significant difference of inadvertent parathyroidectomy between the 2 groups: 0.5% versus 3.9% in lobectomy (P=0.035) and 0.6% versus 5.2% in total thyroidectomy (P=0.012). However, the rates of hypoparathyroidism were not significantly different (P>0.05). There were no cases of CNP-related adverse effects.