Mucin-producing carcinoma of the gallbladder: evaluation by magnetic resonance cholangiopancreatography in three cases.

We report three cases of mucin-producing carcinoma of the gallbladder, along with the magnetic resonance (MR) findings, especially the findings on a MR cholangiopancreatography. In our cases, linear or curvilinear streaks were detected running along the long axis of an enlarged gallbladder (mucus thread sign). When such findings were seen, a mucin-producing carcinoma of the gallbladder should be included as a differential diagnosis. Thus, gadolinium-enhanced MR imaging is mandatory for the precise diagnosis of the mucin-producing carcinoma of the gallbladder.