Tuesday 19 June 2012
Definition: Duodenal adenomas can occur sporadically or as part of a polyposis syndrome. Both groups carry malignant potential but this is higher in patients with a polyposis syndrome.
Duodenal adenoma with abundant paneth cells.
The majority of sporadic duodenal adenomas are flat or sessile and occur in the second part of the duodenum.
Sporadic duodenal adenoma is an uncommon finding. In a large series from Germany, only 6.9% of 378 duodenal polyps found at 25 000 upper gastrointestinal endoscopies were adenomatous.
Another series similarly found that only 0.4% of 584 endoscopy patients had duodenal polyps, of which 7% were adenomatous.
Most adenomas were found incidentally at endoscopy but occasionally caused bleeding or obstruction of the duodenum or ampulla of Vater.
The distribution of small bowel adenomas shows a predominance at the ampulla and periampullary region, with decreased numbers proximally in the duodenum and distally in the small bowel, with a small peak in the distal ileum.
Historically duodenal adenomas have been managed by radical surgery, which carried significant mortality and morbidity, or more conservative local surgical excision which resulted in high local recurrence rates.
There is growing evidence for the use of endoscopic mucosal resection (EMR) techniques for treatment of sporadic non-ampullary duodenal adenomas, with good outcomes and low complication rates.
Endoscopic submucosal dissection (ESD) carries greater risk of complications and should be reserved for experts in this technique.
The impact of endoscopic resection on the course of polyposis syndromes such as familial adenomatous polyposis (FAP) needs further study.
duodenal tubulous adenoma
duodenal villous adenoma
duodenal tubulovillous adenoma
benign duodenal tumors