A case of flat elevated type adenoma of the duodenum

A 48-year-old woman, was diagnosed to have a flat elevated type polyp in the descending part of the duodenum by upper gastrointestinalendoscopy. The lesion, about 15mm in diameter, had two different colors, white and pink. Magnified endoscopy disclosed a foliar pattern in white willi, and a reticular or sulciform pattern in pink villi on the lesion. Endoscopic mucosal resection was performed. Histological examination revealed that the lesion was tubulovillous adenoma in the white villi and tubular adenoma in the pink villi, and indicated that accumulation of absorbed lipids in absorptive cells at the tip of the villi made the villous color whiter. Case reports of flat elevated adenoma of the duodenum are rare. This case would be valuable because of the variation of microscopic mucosal pattern on one lesion, which was observed by magnifying endoscopy.