Gastric inverted hyperplasic polyp composed only of pyloric glands: a rare case report and review of the literature

Inverted hyperplastic polyp (IHP) in stomach is a rare benign gastric polypoid lesion, characterized by downward growth of hyperplastic mucosal glands into the submucosal layer. In most previous reported cases, gastric IHP showed mixtures of fundic-type gland, pyloric-type gland, and foveolar-type epithelium. Also, a case of IHP composed of only one type of gland is extremely rare. This report describes a case of a 70-year-old man with gastric IHP, composed only of pyloric-type gland. It was removed completely by endoscopic submucosal dissection, and patient showed no recurrence over 2 years after treatment.