Polypoid tumors of the major duodenal papilla: preoperative staging with intraductal US, EUS, and CT - A prospective, histopathologically controlled study

Background: An adenoma-carcinoma sequence also applies to adenomas of the m ajor duodenal papilla. Therefore accurate preoperative diagnosis and tumor staging are essential to select the appropriate patients for adequate treat ment. In a prospective, histopathologically controlled study of tumors of t he main duodenal papilla, the preoperative diagnostic value of ultrasound ( US) catheter probes applied during endoscopic retrograde cholangiopancreato graphy (ERCP) was investigated. Methods: Intraductal US was compared with conventional endoscopic ultrasono graphy (EUS) and computed tomography (CT). In 27 consecutive patients with benign polypoid tumors of the major duodenal papilla (n = 12) and carcinoma s of the papilla (n = 15), respectively, the value of these imaging procedu res in determining tumor visualization, tumor diagnosis and tumor staging a ccording to the TNM classification was assessed. Every patient underwent su rgical resection; histopathologic evaluation of resected specimens served a s the reference standard. Results: Intraductal US was significantly superior to EUS and CT in terms o f tumor visualization (100% vs 59.3% vs 29.6%, respectively). Sensitivity a nd specificity rates for intraductal US and EUS were 100% versus 62.5% and 75% versus 50%, respectively. Overall accuracy rate in tumor diagnosis for intraductal US (88.9%; 24 of 27) was significantly (p = 0.05) superior to E US (56.3%; 9 of 16). The latter did not depict 4 adenomas and 7 carcinomas. Neither intraductal US nor EUS is suitable for detection of distant metast ases. Conclusion: Intraductal US appears to be the most effective imaging method in visualizing, diagnosing and staging tumors of the major duodenal papilla . Combining ERCP with catheter probe sonography offers a new diagnostic mod ality that has some potential advantages for local staging of small tumors of the main duodenal papilla. Consequently, minimally invasive techniques f or resection of seemingly benign tumors of the papilla or, even more so, of small carcinomas should preferably be based on intraductal US.