Total thyroidectomy plus neck dissection in differentiated papillary thyroid carcinoma patients: pattern of nodal metastasis, morbidity, recurrence, and postoperative levels of serum parathyroid hormone

Abstract

Objective: To investigate the pattern of nodal metastasis, morbidity, recurrence rates of papillary thyroid carcinoma (PTC), and parathyroid hormone (PTH) responses following neck dissection (ND) plus total thyroidectomy (TT).

Summary background data: While hypoparathyroidism develops after TT plus ND, little is known of postoperative PTH response.

Methods: Of 155 PTC patients, 82 underwent TT plus bilateral central ND with/without lateral ND, while 73 underwent TT alone. The nodal metastasis pattern was determined and the recurrence, morbidity, and postoperative levels of serum calcium and PTH were compared between 2 groups.

Results: Of the 82 node dissection patients, metastatic nodes were present in the central neck of 51 (62.2%) and the lateral neck of 21 (25.6%) patients, most frequently in the ipsilateral and pretracheal central nodes and lateral jugular nodes. Four regional recurrences (2.6%) were found in 3 patients of the no node dissection group and one of the node dissection group (P = 0.37) during the follow-up lasting a mean 52 months. Overall morbidity and hypocalcemia was higher in the node dissection group than the no node dissection group (41 of 82, 50%; vs. 9 of 73, 12.3%; P < 0.001; 25 of 82, 30.5%; vs. 7 of 73, 9.6%; P = 0.001). Serum PTH levels significantly decreased immediately postoperatively in the node dissection group and remained low for several weeks thereafter.

Conclusions: Serum PTH levels were significantly reduced following ND in PTC patients. Our data suggest that, when performing therapeutic ND plus TT, particular effort should be made to preserve the parathyroid glands and to monitor their function.

FIGURE 1. Changes in total calcium (upper panel) and intact parathyroid hormone (lower panel) levels before and after total thyroidectomy in the with or without neck dissection groups. Values represent mean ± SEM. *t test.

FIGURE 2. Changes in total calcium (upper panel) and intact parathyroid hormone (lower panel) levels before and after total thyroidectomy plus neck dissection in the with or without postoperative hypocalcemia groups. Values represent mean ± SEM. *t test.