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CC BY 4.0 · Surg J (N Y) 2021; 07(04): e307-e313
DOI: 10.1055/s-0041-1736669
Review Article

Risk Benefit Analysis of Routine Thymectomy for Differentiated Thyroid Cancers: A Systematic Review

Pallvi Kaul
1   Department of ENT and Head Neck Surgery, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
,
Priyanka Kaul
2   Department of General Surgery, Government Medical College, Jammu, India
,
Dharma Ram Poonia 
3   Department of Surgical Oncology, All India Institute of Medical Sciences, Jodhpur, India
,
Ashish Jakhetiya
4   Department of Surgical Oncology, Geetanjali Medical College Hospital, Udaipur, Rajasthan, India
,
Vipin Arora 
5   Department of ENT and Head Neck Surgery, University College of Medical Sciences and Guru Teg Bahadur Hospital, University of Delhi, Delhi, India
,
Pankaj Kumar Garg 
6   Department of Surgical Oncology, Shri Guru Ram Rai Institute of Medical and Health Sciences, Dehradun, India
› Author Affiliations Funding Sources None.
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Abstract

Background Central compartment lymph node dissection (CLND) is a part of the surgical management of differentiated thyroid cancer (DTC). Therapeutic CLND is done to address clinically significant central compartment nodes in patients with DTC, while prophylactic CLND is performed in the presence of high-risk features in the absence of clinically significant neck nodes. Removal of thymus—unilateral or bilateral—during CLND to achieve complete clearance of level VI and VII lymph node stations and address thymic metastasis is debatable.

Objective The present systematic review was conducted to summarize the evidence, delineating the role of thymectomy during CLND in patients with DTC.

Methods Electronic databases of PubMed, Embase, and Cochrane were searched from their inception to July 2020 using keywords—thyroid neoplasms or tumors, thyroidectomy, and thymectomy—to identify the articles describing the role of thymectomy during CLND in DTC. A pooled analysis of surgicopathological outcomes was performed using metaprop command in STATA software version 16.

Result A total of three studies and 347 patients—total thyroidectomy (TT) with bilateral thymectomy in 154, TT with unilateral thymectomy in 166, and TT alone in 27 patients with DTC—were included in the systematic review. The pooled frequency of thymic metastasis was a mere 2% in patients undergoing either unilateral or bilateral thymectomy. The routine addition of thymectomy does not result in better lymph node clearance. Unilateral and bilateral thymectomy were associated with high chances of transient hypocalcemia (12.0% and 56.1%, respectively).

Conclusion Routine thymectomy is not warranted during CLND, considering minimal oncological benefit and high risk of postoperative hypocalcemia.

Keywords

Head And Neck Cancer - Thyroid neoplasms - Central compartment node dissection - Thyroidectomy - Thymectomy

Statement of Ethics

All analyses were based on previously published studies. Ethical approval and patient consent forms were not required.


Author Contributions

All authors participated in the study's conceptualization. P.K., P.K.G., and A.J. participated in data collection. P.K., P.K.G., D.P., and V.A. participated in data analysis. All authors participated in writing the original draft; All authors wrote, reviewed, edited, and approved this final manuscript.


Disclosure Statement

The authors have no conflicts of interest to declare.




Publication History

Received: 08 December 2020

Accepted: 25 August 2021

Article published online:
15 December 2021

© 2021. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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