Malakoplakia and colonic adenoma: a rare association

We report the case of a 73-year-old woman who presented respectively a caecal adenocarcinoma, two high-grade dysplastic tubulo-villous adenomas of the right colon, and a well differentiated adenocarcinoma developed on a high-grade dysplastic tubulo-villous adenoma of the left colon. One of the right colonic adenomas was ulcerated and showed typical foci of malakoplakia in the lamina propria. Malakoplakia is a histiocytic inflammatory response that may be associated with inflammatory and infectious diseases, immunosuppressive therapy, or colorectal carcinoma. Association of malakoplakia with colonic adenoma is rare; only three cases have been described in the literature thus far. To verify if this association is more common than usually suspected, we reviewed 100 colonic adenomas measuring at least 2 cm. No other case of malakoplakia associated with adenoma was found. The patient did not suffer from any other inflammatory or infectious disease and she was not under any medication or immunosuppressive therapy. Our observation confirms the isolated association of malakoplakia and colonic adenomas and the rarity of this association.