Endoscopic Diagnosis of Ampullary Tumors Using Conventional Endoscopic Ultrasonography and Intraductal Ultrasonography in the Era of Endoscopic Papillectomy: Advantages and Limitations

diagnosis of ampullary tumors during screening en-doscopy or radiological imaging studies is increasing. Traditional management for ampullary tumors is surgical resec-tion. However, surgical intervention needs radical excision, including excision of the surrounding organs around the am-pulla of Vater. With the development of endoscopic techniques , endoscopic resection for ampullary tumors has largely replaced classical surgical resection for the treatment of ampullary tumors, as it is a less invasive intervention. 1 However , owing to the inherited limitation of resection depth by using the endoscopic procedure, only ampullary adenoma or very early stage cancer of the ampulla of Vater are indicated for endoscopic resection. 2 Radiologic imaging studies, including cross sectional imaging such as computed tomography or magnetic resonance imaging, have poor accuracy for the T-staging of ampullary cancer. 3,4 Therefore, further investigation with another endoscopic modality in conjunction with duodeno-scopic evaluation is needed to identify ampullary lesions suitable for endoscopic resection. In this issue of Clinical Endos-copy, Okano et al. 5 reports the analyzed accuracy of conventional endoscopic ultrasonography (EUS) and transpapillary intraductal ultrasonography (IDUS) for diagnosing ampulla-ry tumors by focusing on finding early-stage tumors as an indication for endoscopic papillectomy (EP) with a snare. EP was used to treat 35 of 48 patients (72.9%) with ampullary tumors. The authors examined the ampullary tumors with EUS and IDUS before endoscopic resection or surgical excision. The overall diagnostic accuracy was the same (85%) for both EUS and IDUS. Diagnostic accuracies for ampullary adenoma or pTis cancer and T1 early-stage cancer were similar with 97% and 73% for EUS, and 94% and 73% for IDUS, respectively. Extension of the tumor into the bile duct and pancre-atic duct was diagnosed with accuracies of 90% and 92% by using EUS, respectively, and 88% and 88% by using IDUS, respectively. Ito et al. 6 reported the results of a similar study of 40 patients. IDUS was more accurate than EUS for ampullary adenoma and T1 (86% vs. 62%), and the overall accuracy in T-staging (78% vs. 63%). The overall accuracy in the assessment of duc-tal invasion for IDUS (90% in both the bile duct and the pan-creatic duct) was very similar to that of EUS (88% in the bile duct and 90% in the pancreatic duct). Endosonographic evaluation, especially EUS, is now widely available; however, there is still no consensus regarding the indication of EUS and/or IDUS to make a therapeutic decision in patients with …