Gastric Heterotopia in the Gallbladder

Lee, Sang In; Kim, Young Soo; Cho, Sung Won; Hahm, Ki Baik; Kim, Jin Hong; Kim, Myung Wook; Joo, Hee Jae

Abstract

Heterotopia (of Ectopia) is defined as the occurrence of normal tissue in an abnormal location. Heterotopic gastric mucosa has been found throughout the length of the gastrointestinal tract from oral cavity to the rectum. Curiously, it is extremely rare in the gailbladder, but when it occurs, it tends to cause symptoms of acute cholecystitis in patients under 20 years of age, and chronic cholecystitis and gallstones in older patients. The heterotopic mucosa results in an intramural mass, a polyp or multiloculated gallbladder. A firm diagnosis of gastric heterotopia is based on the presence of fundic or pyrolic mucosa replete with parietal and chief cells. A clear distinction from intestinal rnetaplasia should be made, but at times may be difficult. Potential complications include mucosal ulceration, obstruction, and hemorrhage. Treatment is cholecystectomy. We report a case of gastric heterotopia in the gallbladder of a 35-year-old-man. Ultrasonography showed fatty change of liver with a 1.5 cm-sized polypoid lesion in the gallbladder. Endoscopic retrograde cholangiography showed a small filling defect, revealed by pooling of the dye in the center, in the body of gallbladder. Laparoscopic cholecystectomy was performed. A sessile polypoid leision with central umbilication was seen in the upper body of gallbladder, without gallstones. The microscopic finding of polypoid lesion consisted of gastric pyloric glands with parietal and chief cells. The surrounding mucosa revealed ordinary gallbladder epithelium without any metaplastic change. We report a case of this condition in which there was a separate loculus lined by gastric epithelium.