Accuracy of preoperative T-staging of gallbladder carcinoma using MDCT

OBJECTIVE. The objective of our study was to evaluate the performance of MDCT in the preoperative T-staging of gallbladder cancer and to determine whether adding multiplanar reconstruction ( MPR) images to axial images can improve the accuracy of MDCT for the T-staging of gallbladder cancer. MATERIALS AND METHODS. Two abdominal radiologists retrospectively reviewed by consensus axial images of portal phase MDCT scans of 118 patients who had pathologically confirmed gallbladder cancers; they then reviewed the axial and MPR images from 53 of the 118 patients who had undergone MPR imaging. Local disease spread was evaluated according to the TNM system, and the results were compared with the pathologic findings using the McNemar test. The MDCT performance to differentiate each T-stage was evaluated using Fisher's exact test. RESULTS. The sensitivities of the ability to differentiate the <= T1 versus >= T2 lesions, <= T2 versus >= T3 lesions, and <= T3 versus T4 lesions were 79.3%, 92.7%, and 100%, respectively; the specificities were 98.8%, 86%, and 100%, respectively ( p < 0.0001). The overall accuracy for the T-stage was 83.9%. In the 53 patients with MPR images, the combined reading of the axial and MPR images increased the diagnostic accuracy compared with axial image reading only from 71.7% to 84.9%, a statistically significant degree ( p = 0.0233). CONCLUSION. MDCT provided 83.9% accuracy in the diagnosis of the local extent of gallbladder carcinomas, thereby showing acceptable sensitivity and specificity. The addition of MPR images to the axial CT data increased the accuracy.