RESUMEN
BACKGROUND/AIMS: We investigated the efficacy of endoscope guided transabdominal ultrasonography (EGTUS) for the evaluating the depth of colorectal cancer invasion. METHODOLOGY: The subjects were 52 patients with colon cancer and 30 patients with rectal cancer who underwent transabdominal US and curative surgery. During endoscopy, we applied transabdominal US by filling the area around the tumor with de-gassed water. The accuracy of depth invasion assessment using EGTUS was compared with that using endoscopic, computed tomography (CT), surgical or histological findings. RESULTS: The tumor detection rate was 75.6% (62/82), 88.5% (46/52) for colon cancer and 53.3% (16/30) for rectal cancer. The diagnostic accuracies of EGTUS, endoscopic, CT and surgical findings were 87.1% (54/62), 73.2% (60/82), 66.7% (46/69), 65.9% (54/82), respectively. The diagnostic accuracy of EGTUS was 100% (2/2), 66.7% (4/6), and 90.0% (44/49) for T1, T2 and T3 cancer, respectively. CONCLUSION: The results suggest that EGTUS is useful for evaluating preoperative T staging of colorectal cancer.