Objective: To investigate and compare the efficacy of using nanocarbon tracer technique and modified endoscopic-assisted thyroidectomy (Miccoli surgery) and their parathyroid protection effects in total thyroidectomy for patients with papillary thyroid carcinoma (PTC).
Methods: The clinical data of 117 PTC patients undergoing total thyroidectomy were retrospectively analyzed. Of the patients, 31 cases underwent nanocarbon mark during operation (nanocarbon group), 56 cases underwent modified Miccoli surgery (Miccoli group), and the other 30 cases underwent conventional surgery (conventional group). The surgical variables, pre- and postoperative serum levels of calcium and parathyroid hormone (PTH), postoperative scores of visual analogue scale (VAS) and numerical scoring system (NSS), and the incidence of transient or permanent superior laryngeal nerve (SLN) and recurrent laryngeal nerve (RLN) injuries, as well as the occurrence of hypoparathyroidism, hypocalcemia and tumor recurrence were compared among the three groups.
Results: The preoperative data were comparable among the three groups. The operative time was significantly prolonged, but the length of incision and intraoperative blood loss and amount of postoperative drainage were significantly reduced in Miccoli group compared with the other two groups (all P<0.05). There were no significant differences in number of lymph node dissected and length of postoperative hospital stay among the three groups (P>0.05), but the number of metastatic lymph nodes detected in nanocarbon group was significantly higher than that in conventional group (P<0.05). On 1 h to 7 d after operation, the serum calcium and PTH levels in both nanocarbon group and Miccoli group were significantly higher than those in conventional group (all P<0.05), while no significant differences were noted between the former two groups (all P>0.05); the VAS scores in Miccoli group were significantly lower than those in the other two groups, and in nanocarbon group were significantly lower than those in conventional group (all P<0.05). There were no significant differences in serum calcium and PTH levels as well as VAS scores among the three group at one month after operation (all P>0.05). At 3 and
6 months after operation, the NSS scores in Miccoli group were significantly lower than those in the other two groups, and in nanocarbon group were significantly lower than those in conventional group (all P<0.05). All patients were followed up for 18 to 41 months. There was no significant difference in incidence of SLN injury among the three groups (P>0.05); the incidence of RLN injury, hypoparathyroidism and hypocalcemia in either nanocarbon group or Miccoli group were significantly lower than those in conventional group (all P<0.05), but all showed no significant differences between nanocarbon group and Miccoli group (all P>0.05). The recurrence rates had no significant differences among the three groups (P>0.05).
Conclusion: The nanocarbon technique and modified Miccoli procedure can both effectively protect the parathyroid function in total thyroidectomy for PTC patients. The nanocarbon technique has better thoroughness in lymph node dissection, while the modified Miccoli procedure is more minimally invasive.