A Case of Xanthogranulomatous Appendicitis Difficult to Differntiate from an Appendiceal Tumor

Abstract

A 67-year-old woman was admitted with abdominal pain. Laboratory data on admission showed a high inflammatory response. CT showed wall thickness of the appendix with a poor contrast-enhanced, 4-cm mass at the apex and right hydronephrosis. She was diagnosed as having an appendiceal tumor and right hydronephrosis associated with ureteral stenosis. Colonoscopy showed no apparent mass at the orifice of the appendix. Because an appendiceal malignancy could not be completely excluded, ileocecal resection with D3 lymph node dissection was performed. The tumor showed inflammatory cell infiltration consisting mainly of foamy histiocytes and xanthogranulomatous inflammatory lesions composed of granulation tissue. The tumor was finally diagnosed as xanthogranulomatous appendicitis. Although there are many reports of xanthogranulomatous change occurring in the gallbladder and kidneys, such change in the appendix is rare. Therefore, this case of xanthogranulomatous appendicitis that was difficult to differentiate from an appendiceal tumor is reported.