Value of the Cervical Compartments in the Surgical Treatment of Papillary Thyroid Carcinoma

Abstract

In the treatment of papillary thyroid carcinoma (PTC), supplementary lymph node dissection (LND) is not well standardized. The purpose of this study was to evaluate the significance of the cervical compartments in the lymphatic spread of PTC and the impact of modified radical neck dissection (MRND) as an additional surgical procedure to thyroid resection. From 1999 to 2002, LND of the central compartment (compartment A) was performed in 39 patients. Among this group, additional MRND of the ipsilateral compartment (compartment B) and the contralateral compartment (compartment C) was performed in 29 and 15 patients respectively, who met the selection criteria. The mean number of nodes resected was 11 (5-22) in compartment A, 23 (8-37) in compartment B, and 22 (10-31) in compartment C. Histopathologic findings revealed node invasion of compartment A in 25 patients (64.1%), of A and B in 20 patients (51,2%) and of A, B, and C in 13 patients (33.3%). From the 25 patients with metastases in compartment A, 80% (20 patients) already had metastases in compartment B and 52% (13 patients) had metastases in all three compartments. All patients free of metastasis (M0) in compartment A were also metastasis free in both lateral compartments. Postoperative whole-body scanning I(131) in M0 patients showed no uptake at all. Mapping of the cervical anatomy in compartments seems to be a useful taxonomy for clarifying the lymphatic spread of PTC. Patients having PTC without metastasis in compartment A are almost certainly disease free at the time of operation. Lymph node metastasis in the central compartment appears to be a valuable indicator of lymphatic invasion of the lateral compartment and a strong indication for performance of a unilateral or bilateral MRND to complete the surgical removal of tumor.

Correlation between Central and Lateral Neck Dissection in Differentiated Thyroid Carcinoma

“…Some studies have compared the results of CND and LND status, but the indication for LND remains theraeutic [7,8,10,16]. The mediastinal subsite of the CND was included in the lateral compartment in the study by Machens [8], making it difficult to compare the results of this study with those of other studies.…”

“…A very low percentage of positive LND with negative CND was observed, while a high risk of lateral metastases was observed in the case of positive CND. The low percentage of "skip" metastasis (2.17% of patients) compared to other studies (6 to 19.7%) [6,8,26,27] is probably due to the fact that LND was performed systematically, in contrast with other studies in which LND was only performed in the case of suspected lymph node involvement on preoperative examination [7,8,10]. The only case of "skip" metastasis in the present series concerned a patient with lateral cervical lymph node that was already positive at fine-needle aspiration cytology for metastasis of papillary thyroid carcinoma revealing the cancer.…”

“…However, "skip" metastases (positive nodes in the LND, and negative nodes in the CND) have been reported in the literature in 6% to 19.7% of papillary carcinomas [6][7][8] and 4.2% to 5.5% of micropapillary carcinoma [9]. This rate may also be underestimated, as it includes patients undergoing therapeutic rather than prophylactic LND [7,8,10,11]. Various types of neck dissection were performed in previous series [11] and, in the study by Machens [8], the mediastinal subsite was included in the LND and the criteria for lateral lymph node clearance were not well defined [8].…”

Is central neck dissection a safe procedure in the treatment of papillary thyroid cancer? Our experience

“…In line with these observations, some operators have underlined the advantage of routinely combining CND and primary thyroidectomy [6,12,14,[18][19][20]. This approach has also been included in the guidelines of the American Thyroid Association [21].…”

Predictive Factors for Different Subgroups of Central Lymph Node Metastasis in Unilateral Papillary Thyroid Carcinoma

“…However, there are higher morbidity rates associated with CLND, along with higher rates of transient hypoparathyroidism and vocal cord palsy [23,24]. The rates of permanent hypoparathyroidism after LN dissection in differentiated thyroid cancer patients have been reported to range from 3 to 4%, and the rates of transient vocal cord paralysis have been reported to range from 3 to 6% [20,25]. In this study, permanent hypoparathyroidism occurred in 4/184 patients, and transient hypoparathyroidism occurred in 48/184 patients.…”