Cecum malakoplakia: a tumor-like lesion with coexistent adenocarcinoma.

We report the case of a 75-year-old Caucasian male who presented with acute abdomen and fecal leakage from his old appendectomy scar and required exploratory laparotomy. A large cecal mass was found and a right colectomy was performed. At pathology, the neoplastic mass was identified as malakoplakia with a small area corresponding to a moderately differentiated colonic adenocarcinoma. Occurrence of malakoplakia in the cecum, associated with adenocarcinoma, is extremely rare if we take into account the limited number of the reported cases of its coexistence with colonic cancer; our case is the second report of such an entity in the cecum. The unusual presence of fistula to the appendectomy scar may be related to the infiltrative nature of the histiocytes constituting this process. Immunochemical studies can assist in the histopathologic differentiation of malakoplakia from other entities that might represent with this tumor-like configuration.