Endoscopic ultrasonography assessment in preoperative staging for carcinoma of ampulla of Vater and extrahepatic bile duct.

OBJECTIVE: To evaluate preoperatively the extent of primary tumor, involvement of regional lymph node, and distant metastasis of ampullary carcinoma and extra hepatic bile duct carcinoma.

METHODS: 28 patients with ampullary carcinoma and the 18 patients with extrahepatic bile duct carcinoma were subjected to endoscopic ultrasonography (EUS). The results were compared with those of surgical explorations and pathological findings of the resected specimens for evaluating the accuracy of preoperative staging of EUS. 46 patients underwent surgical explorations. Radical resection with detailed pathological study was done for 22 patients with resectable ampullary carcinoma and 18 patients with extrahepatic bile duct carcinoma. Carcinomas of ampulla of Vater and extrahepatic bile duct were staged according to the tumor, nodes, metastasis (TNM) classification.

RESULTS: The accurate rate of EUS in assessing the extent of cancer invasion was 81.8% for ampullary carcinoma, and 72.2% for extrahepatic bile duct carcinoma. The accuracy of EUS in predicting regional lymph node metastasis was 59% for ampullary carcinoma, and 61.1% for extrahepatic bile duct carcinoma. Invasion of portal vein was correctly predicted by EUS in 2 of 3 patients, but the 3 cases of liver metastasis were not detected by EUS.

CONCLUSIONS: EUS is an effective method for the evaluation of the extent of invasion of ampullary carcinoma and extrahepatic bile duct carcinoma as well as the involvement of regional lymph node before operation. Because of its limited penetration depth, however, EUS is inadequate in the assessment of liver metastasis.