Mucin-producing carcinoma of the gallbladder associated with primary sclerosing cholangitis and ulcerative colitis.

Mucin-producing carcinoma of the gallbladder is very rare. We report here a case of mucin-producing carcinoma of the gallbladder associated with primary sclerosing cholangitis (PSC) and ulcerative colitis (UC). A 74-year-old female had been treated with salazosulfapyridine and ursodesoxycholic acid becase of UC and PSC. After 7 years of treatment, laboratory data showed that the liver function took a turn for the worse, and the patient was admitted to our hospital for further examination. Enhanced computed tomography and ultrasonography showed an enlarged gallbladder associated with wall thickening and diffuse papillary protrusion. Endoscopic retrograde cholangiography showed stenosis and dilatation of the bile duct, which were compatible with PSC. Under the diagnosis of an early carcinoma of the gallbladder, we performed simple cholecystectomy. The tumor showed a papillary growth pattern located diffusely in the gallbladder with a massive amount of mucin filling the gallbladder. Histologically, it was diagnosed as a papillary adenocarcinoma localized in the mucosal layer. To the best of our knowledge, this is the first case of mucin-producing carcinoma of the gallbladder associated with PSC and UC. PSC and UC patients should be regarded as a high-risk group not only for cholangiocarcinoma but also carcinoma of the gallbladder.