Xanthomatous pseudotumor of the small intestine following treatment for Burkitt's lymphoma.

A 9-year-old boy with a large mass in the right lower quadrant of the abdomen was diagnosed as having disseminated Burkitt's lymphoma by pleural fluid aspirate. After 4 months of chemotherapy, he developed acute small-bowel obstruction. A resected ileal segment contained a bright-yellow annular submucosal tumor, histologically a xanthoma, that infiltrated the muscularis propria and serosa. No residual lymphoma was identified. We believe that the small-bowel xanthoma in this child is an unusual, nonneoplastic, treatment-related sequela of lymphoma cell lysis and histiocytic scavenging of lipid-membranous debris.