Differentiation of branch duct intraductal papillary mucinous neoplasms from serous cystadenomas of the pancreas using contrast-enhanced sonography.

OBJECTIVES: The purpose of this study was to determine whether contrast-enhanced sonography can improve the ability to differentiate branch duct intraductal mucinous neoplasms from serous cystadenomas of the pancreas compared to conventional (unenhanced) sonography alone.

METHODS: Between March 2008 and May 2012, there were 20 patients with branch duct intraductal mucinous neoplasms and 25 with serous cystadenomas in our institute, for whom preoperative conventional and contrast-enhanced sonographic results were available. The final diagnosis was obtained by histopathology. Various conventional and contrast-enhanced sonographic characteristics were retrospectively evaluated by 2 radiologists in consensus. A receiver operating characteristic curve analysis was used to evaluate the diagnostic value of conventional and contrast-enhanced sonography for discriminating between the two entities.

RESULTS: Three conventional sonographic characteristics (microcysts, cysts with internal echoes, and main pancreatic duct dilatation) and 2 contrast-enhanced sonographic characteristics (communication between the lesion and main pancreatic duct and enhancement of mural nodules) significantly improved the ability to differentiate branch duct intraductal mucinous neoplasms from serous cystadenomas. The area under the receiver operating characteristic curve increased from 0.691 with conventional sonography to 0.859 with combined contrast-enhanced and conventional ultrasonography (P = .043).

CONCLUSIONS: In this series of patients, the addition of contrast-enhanced sonography to conventional sonography improved the ability to differentiate branch duct intraductal mucinous neoplasms from serous cystadenomas.