Morbidity Outcomes of Prophylactic Central Neck Dissection with Total Thyroidectomy versus Total Thyroidectomy Alone in Patients with Node Negative Papillary Thyroid Cancer: A Meta-Analysis of Observational Studies

Abstract

Objective: The primary objective of this meta-analysis is to compare locoregional recurrence, vocal cord paralysis, and permanent hypoparathyroidism in patients with thyroid papillary carcinoma without neck node metastases, after total thyroidectomy with and without prophylactic central neck dissection.
 Methods: Two independent reviewers performed a detailed literature search of MEDLINE (PubMed), HERDIN and Cochrane Library electronic databases to assess research studies until 2018 for inclusion. The primary endpoints of locoregional recurrence, permanent hypoparathyroidism, and vocal cord paralysis were included in the assessment.
 Design: Meta-Analysis of Retrospective Cohort Studies
 Setting: University Hospitals and Tertiary Referral Centers
 Participants: Patients with node-negative papillary thyroid cancer who underwent either total thyroidectomy alone or total thyroidectomy with prophylactic central neck dissection (either unilateral or bilateral).
 Results: This meta-analysis showed that there is a significantly increased risk for locoregional recurrence in the total thyroidectomy alone group (1.96% TT with pCND VS 2.60% TT, RR=0.62, 95% Cl=0.40-0.95, p=.03), permanent hypoparathyroidism in the total thyroidectomy with prophylactic central neck dissection group (5.72% TT with pCND vs 3.34% TT, RR=2.19, 95% Cl=1.62-2.98, p=.00001) and no significant difference for vocal cord paralysis between the 2 groups (RR=1.56, 95% Cl=0.86-2.84, p=.14).
 Conclusion: This meta-analysis revealed that performing pCND in patients with node-negative PTC increases the risk of morbidity for hypoparathyroidism but not for vocal cord paralysis. More importantly, the incidence of recurrence is decreased in the pCND group, which may have implications on the overall survival of patients. The benefit of performing pCND may outweigh the risk but the role of prophylactic CND in the treatment of patients with PTC with clinically negative lymph nodes is still debatable in terms of overall survival.
 
 Keywords: thyroidectomy, complications; neck dissection; papillary thyroid carcinoma; lymph node dissection; recurrence; vocal cord paralysis; hypoparathyroidism