The aim of this retrospective study was to determine the diagnostic value of preoperative computed tomography (CT) and magnetic resonance imaging (MRI) in predicting the resectability of papillary thyroid carcinoma around the carotid artery.
Between January 2004 and December 2009, 8 patients presented with papillary thyroid carcinoma for which pathological and surgical findings could be compared. Tumor involvement of the carotid artery around more than 225° of its circumference was used to predict carotid artery invasion. If loss of the intervening fat plane was not presented, no carotid artery invasion was predicted.
Although 6 patients revealed carotid artery invasion radiologically, 3 of these 6 patients had carotid invasion pathologically, an accuracy of 62.5% (5 of 8). The discontinuity of the arterial wall corresponded to the result of pathological tumor invasion.
We conclude that carotid artery invasion on CT and MR images can be accurately diagnosed by discontinuity of its wall regardless of measurement of the tumor circumference of the carotid artery. It is thought that carotid artery invasion is not predicted when small vessels between the tumor and carotid artery are recognized.