Heterotopic Salivary Gland Tissue at the Hepatic Flexure of the Large Intestine: A Case Report

The occurrence of heterotopic tissue in the large intestine is unusual. The most common heterotopic tissue type described is gastric-type mucosa. On the other hand, heterotopic salivary gland tissue in the large intestine is extremely rare. To the best of the authors' knowledge, only five cases of heterotopic salivary gland in the large intestine have been reported, and all cases arose in the left colon. One out of five cases arose in the sigmoid colon, and the four other cases were found in the rectum-anal canal region. Endoscopically, they usually appeared as a polyp. The presentation of the patients was rectal bleeding or asymptomatic. Heterotopic salivary gland tissue in the colon has not been reported in Korea. This paper reports a case of heterotopic salivary gland tissue at the hepatic flexure of the colon and reviews the literature on similar cases. A 55-year-old male underwent large bowel endoscopy for colorectal carcinoma screening. The colonoscopy revealed five polyps. A sessile polyp at the hepatic flexure, 0.6 cm in size, was resected in a piecemeal manner. The histopathologic findings revealed a salivary gland with mixed mucinous-serous features and ducts. The other four polyps all were diagnosed as tubular adenoma with low-grade dysplasia.