Locally advanced thyroid cancer: can CT help in prediction of extrathyroidal invasion to adjacent structures?
OBJECTIVE
The purpose of this study was to determine the diagnostic accuracy of CT for detecting extrathyroidal invasion of thyroid cancer to adjacent structures.


METHODS
Eighty-four patients (19 men, 65 women; age range, 19-84 years; mean, 54.2 +/- 15.4 years) with 86 malignant tumors of the thyroid with extracapsular extension (37 T3, 49 T4) were retrospectively enrolled in this study. Two radiologists independently evaluated the CT findings of invasion of thyroid cancer into the trachea, esophagus, common carotid artery, internal jugular vein, and recurrent laryngeal nerve. These results were compared with the surgical and histopathologic findings.


RESULTS
The mean sensitivity, specificity, and accuracy of CT were as follows: 59.1%, 91.4%, and 83.2% for tracheal invasion; 28.6%, 96.2%, and 90.7% for esophageal invasion; 75.0%, 99.4%, and 98.8% for invasion of the common carotid artery; 33.3%, 98.8%, and 97.1% for invasion of the internal jugular vein; and 78.2%, 89.8%, and 85.5% for invasion to the recurrent laryngeal nerve. Interobserver agreement was moderate to good in the five categories of extrathyroidal invasion with a mean kappa value of 0.65 (range, 0.49-0.77).


CONCLUSIONS
Although the effectiveness is limited by low sensitivity, CT may be a valuable tool for evaluation of extrathyroidal invasion of thyroid cancer to adjacent structures.
Seo
Young Lan
YL
Department of Radiology, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Republic of Korea.
Yoon
Dae Young
DY
Lim
Kyoung Ja
KJ
Cha
Ji Hyeon
JH
Yun
Eun Joo
EJ
Choi
Chul Soon
CS
Bae
Sang Hoon
SH
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*