[An inflammatory pseudotumor of the appendix].

A 41-year-old male, complaining of an abdominal pain and suspected of having acute appendicitis, underwent examination on hospitalization. Ultrasonography revealed a tumorous lesion of the appendix. Thus, a laparotomy was performed and mass lesions were found in the mid and distal parts of the appendix. A subsequent histological examination revealed an inflammatory pseudotumor consisting of remarkable eosinophilic cell and fibroblastic infiltrations, similar to that seen in a inflammatory fibroid polyp (Helwig). Although such lesions, polypoid in appearance, have been found to occur in the stomach and intestines, to find them in the appendix is extremely rare. In this instance, as the growth of this mass of lesions was more predominant in the wall rather than in intraluminal area, it was decided that pseudotumor was the appropriate term to describe this case.