Elastofibromatous change of the rectum. A lesion mimicking amyloidosis.

We report the case of a 58-year-old woman who had a 7-year history of multiple myeloma and multiple rib fractures and who presented with dysphagia. She underwent thorough gastrointestinal evaluation to rule out the possibility of amyloidosis. Although upper gastrointestinal biopsies were negative, the rectal biopsy was characterized by extensive smudgy eosinophilic deposits in the submucosa that closely resembled amyloid, except that they were not congophilic. Fibers with serrated borders characteristic of those in elastofibroma were identified and confirmed by means of elastic stain and electron microscopy. Elastofibromatous change of the gastrointestinal tract is a rare lesion that has been reported once previously in association with gastric ulcer. This case illustrates that it may occur as a spontaneous or subclinical finding in the absence of other pathologic lesions. The close resemblance between elastofibromatous change and amyloid deposits necessitates the appropriate histochemical and ultrastructural studies.