Amyloidosis of the alimentary canal: radiologic-pathologic correlation of CT findings

Background: The purpose of the study was to describe the computed tomograph ic (CT) findings of the alimentary canal and mesentery in amyloid infiltrat ion of the gastrointestinal (GI) tract and to correlate the CT findings wit h histologic extent and distribution and with amyloid subtype. Methods: Abdominal CT scans performed between 1988 and 1997 on patients wit h pathologically proven amyloidosis of the alimentary canal were reviewed f or abnormalities of the alimentary canal and mesentery. Histology was grade d for extent of mucosal, submucosal, and muscularis propria involvement and for degree of interstitial and vascular distribution. CT findings were cor related with histologic extent, histologic distribution, and amyloid histoc hemical type. Results: Twenty-three patients were included. Four (17%) had bowel wall thi ckening, which was associated with a higher submucosal extent and interstit ial distribution than in patients with normal bowel by CT. Four (17%) patie nts had bowel wall dilatation without thickening, which was not associated with statistically significantly different histology than in patients with normal bowel by CT. There was no statistically significant correlation betw een CT findings and histochemical subtype. Mesenteric soft tissue infiltrat ion was seen in two patients, and mesenteric adenopathy was seen in one pat ient. Conclusions: Normal bowel is a common abdominal CT finding in amyloidosis o f the alimentary canal. When findings are present, GI wall thickening and/o r bowel wall dilatation without wall thickening may be seen. Bowel wall thi ckening on CT correlates with submucosal extent and interstitial distributi on of disease. Soft tissue infiltration and adenopathy are also occasionall y seen.