The incidence and risk factors for central lymph node metastasis in cN0 papillary thyroid microcarcinoma: a meta-analysis

Abstract

Although there have been many studies identifying clinical and pathologic factors that may predict central lymph node metastases (CLNM) in papillary thyroid microcarcinoma (PTMC) patients without clinically cervical lymph node metastasis (cN0), the results were inconsistent. And whether prophylactic central lymph node dissection (pCLND) should be performed in cN0 PTMC remains controversial. The EMBASE, PubMed, MEDLINE and the Cochrane Library were searched until Oct 2015 to identify relevant studies. Primary outcomes were clinical and pathologic factors for CLNM. Secondary outcomes included CLNM rate, surgical complications of hypocalcaemia and recurrent laryngeal nerve(RLN) injury and neck recurrences. Statistical analysis was performed using Stata 12.0. Fourteen eligible studies enrolling 4573 patients were included in this meta-analysis. The overall incidence of CLNM was 33 % (95 % CI 29-37). An elevated risk of CLNM was significantly associated with male gender (OR 2.33, 95 % CI 1.71-3.17), age <45 years (OR 1.27, 95 % CI 1.08-1.48), tumor size >5 mm (OR 2.16, 95 % CI 1.87-2.50), multifocality (OR 1.73, 95 % CI 1.45-2.05), extrathyroidal extension (OR 1.99, 95 % CI 1.66-2.37) and lymphovascular invasion (OR 3.87, 95 % CI 1.64-9.10), but not with thyroid bilaterality (OR 1.41, 95 % CI 0.89-2.22) and chronic lymphocytic thyroiditis (OR 0.98, 95 % CI 0.66-1.47). The pooled frequency of permanent hypocalcaemia, permanent RLN injury and neck recurrences was 1.1, 0.5 and 2.8 %, respectively. cN0 PTMC patients have a considerable CLNM rate and have a low pooled incident of surgical complications and neck recurrences with pCLND. Six unfavorable clinical and pathologic factors, which were significantly associated with CLNM, were identified. These findings may help guide the application of pCLND or subsequent treatment in cN0 PTMC.

Prediction of central lymph node metastasis in patientswith thyroid papillary microcarcinoma

“…Another study by Siddiqui et al (28) showed that younger age (age < 45 years), multifocality, and extrathyroidal extension were predictors of CLNM. Our data showed that male sex and tumor size were not predictive for CLNM, in contrast to findings by others (18,29,30). In addition, Siddiqui et al reported that the risk of lymph node metastasis in incidental PTMC was not significantly different compared with known/suspected PTC (28).…”

“…Central lymph node metastasis is still a risk in patients with PTC or PTMC; we found that 29.5% of all patients had CLND. Despite the fact that many studies have shown that lymph node metastasis in PTMC is one of the main predictors of recurrence (18)(19)(20), there is no consensus as to whether prophylactic neck dissection should be routinely included in the surgical treatment. The American Thyroid Association guidelines recommend inclusion of neck dissection for PTC only in the setting of clinically evident lymph node metastasis (21).…”

Expression of cytokeratin-19 (CK19) in the classical subtype of papillary thyroid carcinoma: the experience of one center in the Silesian region

“…In turn, papillary thyroid carcinoma (PTC) is the most common thyroid malignancy, accounting for 80-90% of all thyroid malignant tumors [7][8][9]. As with thyroid carcinomas in general, the prognosis of PTC is favorable, and the ten-year survival rate of the classical subtype of PTC (CSTPTC) is over 90% [9].…”

The synergic effect of BRAF^V600E mutation and multifocality on central lymph node metastasis in unilateral papillary thyroid carcinoma

“…Multifocality also frequently exhibits in PTC. Certain studies have indicated that multifocal carcinoma in PTC is positively associated with the incidence of CLNM [14,15], while other studies have argued that there is no association between multifocality and CLNM [16]. In addition, multifocality has found to significantly increase the incidence of recurrence [17].…”