Use of color Doppler ultrasonography for the prediction of malignancy in follicular thyroid neoplasms: systematic review and meta-analysis.
OBJECTIVE
The purpose of this systematic review was to obtain summary estimates of the diagnostic accuracy of color Doppler ultrasonography (CDU) in predicting malignancy in thyroid follicular neoplasms (FNs).


METHODS
We searched Medical Subject Headings together with the search terms "follicular," "thyroid," and "Doppler" in the MEDLINE, Web of Science, and Excerpta Medica databases as well as the Latin American and Caribbean Health Sciences Literature database, after which we performed manual searches of the reference lists to locate additional studies. There were no language restrictions. We included studies that assessed the diagnostic accuracy of CDU in identifying malignancy in thyroid FNs. The assessments of the quality and extraction of data were performed by 3 independent reviewers.


RESULTS
We included 4 studies, which collectively evaluated 457 thyroid FNs, 67 of which had been classified as malignant based on the evaluation of surgical biopsy samples. Moderate, rich, predominant, or exclusive internal flow on CDU of thyroid FNs was considered indicative of malignancy. The overall sensitivity of CDU was 85% (95% confidence interval [CI], 74%-93%), with an overall specificity of 86% (95% CI, 82%-89%). The overall prevalence was 14.7%, and the positive and negative predictive values were 51% and 97%, respectively. The positive likelihood ratio was 6.07, and the negative likelihood ratio was 0.18.


CONCLUSIONS
Predominant internal flow seen on CDU is associated with malignancy of thyroid FNs. Absence of internal flow or predominantly peripheral flow indicates a low probability of thyroid FN malignancy.
Iared
Wagner
W
Department of Internal Medicine, Brazilian Cochrane Center, São Paulo, Brazil. wagneriared@gmail.com
Shigueoka
David Carlos
DC
Cristófoli
Júlio Cesar
JC
Andriolo
Regis
R
Atallah
Alvaro Nagib
AN
Ajzen
Sérgio Aron
SA
Valente
Orsine
O
D018263:Adenocarcinoma, Follicular / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D015995:Prevalence; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D018615:Ultrasonography, Doppler, Color / Q000706:statistics & numerical data*