The role of carbon nanoparticles in guiding central neck dissection and protecting the parathyroid in transoral vestibular endoscopic thyroidectomy for thyroid cancer

INTRODUCTION: Transoral vestibular endoscopic thyroidectomy (TOET) is sometimes used in young and middle-aged patients with papillary thyroid microcarcinoma (PTMC), but it is still difficult to identify lymph nodes (LNs) and parathyroid glands (PGs). Carbon nanoparticle (CN) is a novel lymph node tracer and has been widely used in open thyroid surgery. AIM: To evaluate the efficacy of CN in identifying LNs and preserving PGs in TOET with central neck dissection (CND). MATERIAL AND METHODS: A total of 72 PTMC patients undergoing TOET with CND were retrospectively enrolled from January 2017 to January 2019. Patients were divided into a CN group (n = 38) and a control group (n = 34). The parameters including pathological characteristics, surgery related indicators, serum Ca(2+) and parathyroid hormone (PTH) levels were compared. RESULTS: No significant differences were found in patient characteristics, operative complications and superior PGs preserved in situ (all p > 0.05). Total LNs and number of LNs less than 5 mm were significantly higher in the CN group than in the control group (p = 0.021, p < 0.01). The number of superior PGs preserved in situ discovered in the CN group was greater than the control group (p = 0.038). Serum PTH and Ca(2+) levels dropped markedly in each group after surgery and gradually recovered in time. The CN group recovered faster than the control group. CONCLUSIONS: CN may be a good choice for TOET for PTMC because of better protection and faster recovery of parathyroid function, and more LNs removed.