Case of pediatric traditional serrated adenoma resected via endoscopic submucosal dissection.

Traditional serrated adenoma (TSA) is a type of serrated polyp of the colorectum and is thought to be a precancerous lesion. There are three types of serrated polyps, namely, hyperplastic polyps, sessile serrated adenomas/polyps, and TSAs. TSA is the least common of the three types and accounts for about 5% of serrated polyps. Here we report a pediatric case of TSA that was successfully resected by endoscopic submucosal dissection (ESD). This rare case report describes a pediatric patient with no family history of colonic polyp who was admitted to our hospital with hematochezia. On colonoscopy, we found a polypoid lesion measuring 10 mm in diameter in the lower rectum. We selected ESD as a surgical option for en bloc resection, and histopathological examination revealed TSA. The findings in this case suggest that TSA with precancerous potential can occur in children, and that ESD is useful for treating this lesion.