Preoperative local staging of colosigmoideal cancer: air versus water multidetector-row CT colonography.

PURPOSE

The authors sought to evaluate the diagnostic accuracy of multidetector-row computed tomography (MDCT) performed with two different hypodense endoluminal contrast agents for the preoperative staging of colosigmoideal cancer.

MATERIALS AND METHODS

Seventy consecutive patients with an endoscopically and histologically proven diagnosis of colosigmoideal cancer underwent MDCT examination. Thirty-five patients were evaluated with water MDCT colonography and the remaining 35 with air MDCT colonography. Patients were randomly assigned to the air or water groups for staging. Transverse images and multiplanar reconstructions (MPR) were retrospectively examined by two blinded expert radiologists in order to assess T and N parameters, and the results were compared with histological findings.

RESULTS

The overall diagnostic accuracy of MDCT was 68.6% for water and 62.8% for air colonography. In the evaluation of the T parameter, the accuracy values were 88.6% for water and 80% for air colonography. In staging of the N parameter, the accuracy values were 77.1% and 74.3% for water and air MDCT colonography, respectively.

CONCLUSIONS

MDCT examination can be proposed for the local staging of colosigmoideal cancer. Water is more accurate than air in evaluation of the T parameter, whereas the kind of endoluminal contrast material does not influence the definition of the N parameter.