Endoscopic ultrasonography in the diagnosis of depth invasion and lymph node metastasis of carcinoma of the papilla of Vater.

To evaluate diagnostic accuracy of endoscopic ultrasonography (EUS) on the extent of carcinoma of the papilla of Vater, 28 patients were preoperatively evaluated using our EUS grading system. EUS was accurate in diagnosing carcinoma infiltration into the duodenal proper muscle layer (100%) and into the pancreas (75%). When compared with postoperative histologic findings, the overall accuracy of EUS in assessing local infiltration was 89.3%. Misdiagnoses occurred in three cases due to microinfiltration of the carcinoma. Lymph node metastasis around the pancreatic head was accurately diagnosed in nine cases; however, mesenteric lymph node metastasis could not be detected in four cases because the tumor was far from the scanning site.