Korean J Pathol.  2010 Oct;44(5):521-527.

Application of Bethesda System for Reporting Thyroid Aspiration Cytology

• Lee K
• Jung CK
• Lee KY
• Bae JS
• Lim DJ
• Jung SL

Abstract

BACKGROUND
The Bethesda classification system for reporting on thyroid fine-needle aspiration (FNA) cytology was recently proposed by the National Cancer Institute, USA. We aimed to report our experience with applying this system for thyroid FNA, with a focus on comparing it with the four categorical system.
METHODS
We retrospectively reviewed the 4,966 thyroid FNAs that were performed at the Seoul St. Mary's Hospital between October 2008 and September 2009. All the FNAs were classified according to the Bethesda system and the four tier system.
RESULTS
The cytologic diagnoses of the Bethesda system included 10.0% unsatisfactory, 67.7% benign, 3.1% atypia of undetermined significance, 0.6% follicular neoplasm, 0.5% follicular neoplasm, Hurthle cell type, 5.1% suspicious for malignancy and 13.0% malignancy. Using four tier system, 10.1%, 67.6%, 9.3%, and 13% were diagnosed as unsatisfactory, negative for malignancy, atypical cells and malignancy, respectively. Of the 4,966 nodules, 905 were histologically confirmed. The specificity of the Bethesda system and the four tier system for diagnosing malignancy was 99.6% and 82.6%, respectively.
CONCLUSIONS
The Bethesda system can classify indeterminate thyroid nodules into more detailed categories and provide clinicians with useful information for management.

Keyword

Biopsy, fine-needle; Thyroid neoplasms; Cytopathology; Diagnostic techniques and procedures

MeSH Terms

Biopsy, Fine-Needle
Diagnostic Techniques and Procedures
National Cancer Institute (U.S.)
Retrospective Studies
Sensitivity and Specificity
Thyroid Gland
Thyroid Neoplasms
Thyroid Nodule