Gastrointestinal System, Pancreatobiliary Tract and Liver

Esophageal adenocarcinomas are believed to follow the intestinal metaplasia–dysplasia–carcinoma pathway. The metaplastic glandular epithelium is lined by a layer of periglandular myofibroblastic cells which regulate many aspects of the epithelial cells like in the intestine (refer to the intestine section for more detailed discussion) [4]. Due to the presence of the periglandular myofibroblastic sheath, benign intestinal epithelial proliferations have a characteristic serrated appearance. Except for the rare serrated adenocarcinomas in the colon which possess other easily discernible characteristic features, genuine serration is rarely seen in gastrointestinal epithelial malignancies. This important feature can be very useful in the diagnosis of well-differentiated carcinomas where invasion is insidious and desmoplasia is not evident.