Gastric inflammatory fibroid polyps: Endoscopic ultrasonographic analysis in comparison with the histology

Background: Histologic diagnosis of inflammatory fibroid polyp is usually difficult on routine endoscopic examinations. The aim of this study was to describe endoscopic ultrasonographic features of gastric inflammatory fibroid polyps. Methods: Endoscopic ultrasonography was performed in 10 patients with gastric inflammatory fibroid polyps before resection. All lesions were resected by either endoscopic removal or gastrectomy and then confirmed histologically as inflammatory fibroid polyps. To evaluate the diagnostic value of endosonography, endoscopic ultrasonographic images of the lesions were analyzed and compared with resected specimens retrospectively. Results: All lesions were located in the second and/or third sonographic layer of the gastric wall without involvement of the fourth layer. The most frequent endoscopic ultrasonographic features were an indistinct margin (90%), and a hypoechoic (80%), homogeneous (90%) echo pattern. Histologically, inflammatory fibroid polyps developed in the deep mucosa and/or submucosa by proliferation of fibrous tissue, but did not have a capsule. Conclusions: The characteristic endoscopic ultrasonographic attributes of gastric inflammatory fibroid polyps are indistinct margin, hypoechogenicity, homogeneous appearance, and location within the second and/or third layer. These findings correlate very closely to the histologic findings.