Elastofibroma. Case report

A case of subscapular elastofibroma in a 61-year-old male was studied by light and electron microscopy. Sixty-two cases of this lesion have been to date reported. At light microscopy, the mass was unencapsulated and consisted of dense collagen bundles with many thick elastinophilic fibers and globules. The ultrastructural examination showed the fibers contained a clear core of mature elastic tissue surrounded by a more electron-dense fibrillar material, which was attributed to newly formed elastin. After elastase digestion, the fibers failed to stain with orcein. The cells were very scanty and identified as fibroblasts. The hypothesis formulated by various authors about the nature of elastinophilic fibers and about the pathogenesis of elastofibroma are reviewed. Our findings seems to support those of most authors, who consider the lesion an abnormally increased reactive production of elastic tissue by fibroblasts in response to a mechanical stimulus.