Imaging studies of intraductal tubulopapillary neoplasms of the pancreas: 2-tone duct sign and cork-of-wine-bottle sign as indicators of intraductal tumor growth

Objective: The objective of this study was to describe the imaging findings for intraductal tubulopapillary neoplasms of the pancreas. Methods: Eleven pancreatic tumors pathologically confirmed as intraductal tubulopapillary neoplasm were retrospectively collected. The dynamic contrast-enhanced computed tomography (CT), magnetic resonance (MR) imaging including MR cholangiopancreatography (MRCP), ultrasound, and endoscopic retrograde cholangiopancreatography (ERCP) results were reviewed. The 2-tone duct sign and cork-of-wine-bottle sign were reviewed as indicators of intraductal tumor growth on CT/MR and MRCP/ERCP images, respectively. Results: A 2-tone duct sign was noted on the dynamic CT images (7/10, 70%) and on the MR imaging (5/8, 63%). The distal main pancreatic duct was dilated in all the patients except one, who had a branch duct lesion. A cork-of-wine-bottle sign was observed on the MRCP image (3/8, 38%) and on the ERCP image (3/6, 50%). Conclusions: Intraductal tubulopapillary neoplasms are rare tumors showing characteristic imaging findings such as the 2-tone duct sign and the cork-of-wine-bottle sign that represent their intraductal growth.