Xanthogranulomatous Inflammation in Terminal Ileum Presenting as an Appendiceal Mass: Case Report and Review of the Literature
A 52-year-old man visited our unit due to right lower quadrant abdominal pain for 3 months. His blood tests revealed a white blood cell count of 11,900 cells/µL with 82% neutrophils, hemoglobin of 12.8 g/dL, platelet count 389,000 cells/µL, C-reactive protein 7.53 mg/dL (range, 1.0 to 0.8), and carcinoembryonic antigen 4.0 ng/mL (range, 0 to 5.0). All other results were normal. Abdominal computed tomography (CT) demonstrated a 5-cm appendiceal mass with inhomogeneous enhancement, edematous bowel wall thickening of the terminal ileum, and multiple enlarged lymph nodes along the ileocolic mesentery (). Colonoscopy showed multiple erythematous nodular lesions in the terminal ileum and appendiceal orifice (). Multiple biopsies of these lesions were obtained, revealing ulcer with acute and chronic inflammation. However, radiological findings highly suggested appendiceal cancer, for which we decided to perform exploratory laparoscopy. A laparoscopy revealed a 5.5× 3 cm mass in the terminal ileum, and laparoscopic right hemicolectomy was performed. A macroscopic study showed a lobulated golden-yellowish mass-like lesion involving the ileal wall and adjacent mesentery. A brown-colored perpendicular lesion had the strong possibility of penetrating foreign material (). The colonic mucosa was relatively well-preserved, and the appendix was buried in an adjacent mass-like lesion without evidence of appendicitis. Microscopically, the mass-like lesion of the ileum showed nodular aggregation of lipid-laden foamy histiocytes and variable numbers of small lymphocytes, plasma cells, and eosinophils, which mainly involved the submucosa and muscle proper with extension into the mesenteric fat tissue (). There were occasional foci of foreign body type giant cell reactions surrounding calcified food materials (). These histological findings were compatible with XGI mainly involving the terminal ileum.