Elastosis and elastofibromatous change in the gastrointestinal tract: a clinicopathologic study of 13 cases and a review of the literature.

We describe 13 cases in which the submucosa and muscularis mucosae of the gastrointestinal tract exhibited a focal or diffuse increase of elastin fibers. This elastosis or elastofibromatous change most commonly manifested as a colonic polyp and usually was found during screening colonoscopy. Gastric and small intestinal cases were less frequent and associated with ulcers or an inflammatory process. The literature includes reports of 13 gastrointestinal elastotic lesions with a topographic distribution similar to that in our series. Histologically, elastosis appears as finely granular and/or fibrillar amphophilic material, sometimes with a fibrous component (elastofibromatous change). The changes occasionally appear centered around blood vessels and often are mistaken for amyloid but are negative for Congo red stain and strongly positive for elastin stain. We believe that this lesion might be more underrecognized than rare. In 2 of 26 cases, elastotic lesions also were present in nongastrointestinal sites.