A Large Gastric Inflammatory Fibroid Polyp.

Inflammatory fibroid polyp (IFP) is an unusual benign gastrointestinal subepithelial tumor (SET). The endosonographic (EUS) features of IFPs were sporadically reported on imaging tips or small case series study. However, the differential diagnosis and optimal treatment of gastric IFP is still challenging. We report an unusual case of a large erosioned and prolapsing gastric submucosal lesion, presenting primarily with obstructive symptoms ("ball valve syndrome") and anemia. On EUS examination, a 50 mm SET in the distal antrum was seen, with hypoechoic but heterogeneous echo-pattern, located in the second and third sonographic layers of the gastric wall (deep mucosal and submucosal). The fourth (muscle) layer was intact; no peri-lesional adenopathies were identified. A decision was made to proceed to endoscopic treatment because of the mentioned symptoms. Histopathologic evaluation of the resected specimen with immunohistochemical staining was consistent with the diagnosis of IFP. IFP rarely reach these large dimensions or cause symptoms. Despite its benign etiology, endoscopic resection was important in both establishing a histologic diagnosis and treatment. EUS was crucial in the differential diagnosis. The literature concerning IFP is also reviewed.