Distance between the esophageal tumor and the aorta measured by using the contrast-enhanced attenuation on computed tomography for predicting this tumor invading aorta.

BACKGROUND AND AIM

Despite remarkable advances in diagnostic modalities, preoperative assessment of the local tumor extent in esophageal cancer is still very difficult. The aim of this study was to evaluate the predictive value of the computed tomography (CT) attenuation value between the tumor and the aorta for esophageal cancer.

METHODS

Consecutive CT values were determined between the center of the tumor and the center of the aorta. The distance between the intersection of the average CT attenuation value of the tumor using the lower CT attenuation value of the inclusion tissues (T-A distance) was determined. The minimal CT attenuation value and the overall circumference of contact area (Picus' angle) were also determined. This study included 101 patients suspected of having a tumor invading the adventitia and evaluated the capacity of these parameters for predicting the aortic invasion.

RESULTS

The T-A distance in patients who were diagnosed without aortic invasion was significantly longer than patients who were pathologically confirmed to have invasion to the aortic wall [pT4(Ao)] (P < 0.05). The minimal CT attenuation value in patients without aortic invasion was significantly lower than pT4(Ao) patients (P < 0.05), although such a difference was not observed for the Picus' angle. The T-A distance (1.3 mm >) is the most reliable feature for predicting the aortic invasion, according to the results of the area under the receiver operating characteristic curve.

CONCLUSIONS

The assessment of the T-A distance is simple and objective, and it can help prevent unnecessary surgery in patients with inoperable tumors.