Prophylactic Central Neck Dissection for cN1b Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

BackgroundThe value of prophylactic central neck dissection (PCND) for papillary thyroid carcinoma (PTC) with clinically evident lateral cervical lymph node metastases (cN1b) remains unclear. Therefore, a systematic review and meta-analysis was conducted to assess the efficacy and safety of PCND.MethodsA comprehensive systematic search was conducted on PubMed, Web of Science, Cochrane library and Embase databases up to September 2021 to identify eligible studies. Controlled clinical trials assessing therapeutic effects and safety of PCND for cN1b PTC patients were included. The risk of bias for each cohort study was assessed using the Newcastle-Ottawa Scale (NOS). The primary outcomes were indexes related to the locoregional recurrence (LRR) and surgical complications. Review Manager software V5.4.0 was used for statistical analysis. A fixed effects model was adopted for the data without heterogeneity, otherwise a random effects model was used.ResultsWe included 4 retrospective cohort studies, which comprised 483 PTC patients. There was no statistically significant difference in the central neck recurrence (CNR) (10.2% vs. 3.8%, relative risk (RR) = 1.82; 95%CI 0.90–3.67; P = 0.09), lateral neck recurrence (LNR) (5.1% vs. 7.7%, RR = 0.47; 95% CI 0.13–1.74; P = 0.26), and overall recurrence (OR) (18.9% vs. 16.9%, RR = 0.77; 95%CI 0.34–1.76; P = 0.54), between LND + PCND group and LND group. Simultaneously, PCND increased the risk of permanent hypoparathyroidism (11.4% vs. 4.5%, RR = 2.70, 95%CI 1.05–6.94; P = 0.04) and overall complications (17.0% vs. 5.3%, RR = 3.28; 95%CI 1.37–7.86; P = 0.008).ConclusionsThis meta-analysis showed that PCND did not have any advantage in preventing LRR for cN1b PTC. Meanwhile, PCND may result in the increased rate of surgical complications. However, the current evidence is limited and more clinical trials are still needed to further clarify the true role of PCND.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/, CRD42021281825.

The Effect of Prophylactic Central Neck Dissection During Hemithyroidectomy on Locoregional Recurrence in Patients With Papillary Thyroid Carcinoma: A Meta-Analysis

Objectives. Hemithyroidectomy is commonly performed in patients with low- to intermediate-risk papillary thyroid carcinoma. The purpose of this meta-analysis was to evaluate the effect of prophylactic central neck dissection on locoregional recurrence in patients undergoing hemithyroidectomy.Methods. A meta-analysis was performed of full-text publications published in English retrieved from the Embase database.Results. The rate of regional recurrence in the central compartment after hemithyroidectomy, with or without prophylactic central neck dissection, was 0.17% and 1.78%, respectively. This difference was statistically significant. Recurrence in the lateral compartment or contralateral thyroid was not affected by prophylactic central neck dissection; the overall rate of recurrence was 1.3% and 5.4%, respectively.Conclusion. Prophylactic central neck dissection significantly reduced the risk of recurrence in the central compartment in patients undergoing hemithyroidectomy.