SHIMURA Hiroki

Hiroki SHIMURA

Department of Laboratory Medicine, Fukushima Medical University

キーワード :

In Japan, ultrasound diagnostic criteria for thyroid nodule were firstly published in 1991，and the second edition of the criteria was published in 1999 from Japan Society of Ultrasonic in Medicine. In order to revise this, members of The Japan Association of Breast and Thyroid Sonology（JABTS）organized a multicenter study.
In this study, the significances of ultrasonographic characteristics of thyroid nodules were evaluated with ultrasonograms from 53 patients by 17 investigators from 15 centers. Univariate analyses showed that border character, shape, and internal echo level are highly significant parameters. A multiple logistic regression showed border character, shape, and internal echo level were recognized as the most important predictors of pathologic diagnosis. The diagnostic criterion with border character and internal echo level yielded 93％sensitivity and 92％specificity. In contrast, strong echoes and marginal hypoechoic zone exhibited lower sensitivity and specificity than others.
Based on this multicenter study, we published the third edition of criteria in 2011，in which ultrasound findings were divided into“primary”and“secondary”findings. ""Primary"" findings include shape, boundary zone sharpness/properties, and internal echoes（echo intensity and homogeneity）, and fine strong echoes and boundary zone hypoechoic bands constitute“secondary”findings. This issue of the criteria is focusing not only papillary carcinoma but also other pathological types of malignancy.
JABTS members are currently performing multicenter studies to investigate the significances of the depth/width ratio and Doppler findings of thyroid nodules. Further revision is expected in the near future.