Histogenesis of unique elastinophilic fibers of elastofibroma: Ultrastructural and immunohistochemical studies

Aspiration cytology of elastofibroma dorsi: Case report with ultrastructural and immunohistochemical findings

“…While EM is not necessary for the diagnosis of elastofibroma, a range of morphologic findings have been reported pointing to developmental abnormalities or defects in synthesis of primitive (fetal) elastin material to degenerative changes within the elastic fibers. 2 Frequently, the adjacent fibroblastic cells contain irregular, granular, focally fine fibrillar aggregated electron-dense elastin protein within the rough endoplasmic reticulum, suggesting aberrant synthesis by the fibroblasts, as in the present case. 9,17 Nakamura et al 15 have proposed that elastofibroma arises due to disturbed elastic fibrillogenesis as a result of chronic irritation or trauma.…”

“…Although it is thought to represent a reactive rather than neoplastic process, recent studies suggest altered elastogenesis rather than a degenerative change as an etiologic mechanism. 1,2 It occurs predominantly in elderly females in the lower subscapular area and is often overlooked clinically due to lack of symptoms. Other rare locations include the greater omentum, stomach, mediastinum, breast, and the forepart of the foot.…”

Nuchal-type fibroma

“…[35][36][37] Elastofibroma generally presents as an ill-defined mass involving the infrascapular chest wall of middleaged and elderly adults. 38,39 Microscopically, this process consists of an admixture of intertwining collagen fibers, fragmented elastic fibers, and scattered fibroblasts. The elastic fibers are best seen with an elastic stain (e.g., Verhoeff's or Gomori's stains) and have a characteristic appearance with a central core and peripherally radiating (spokelike) filaments; a structural resemblance to chenille fibers or pipe cleaners has been noted.…”

Elastofibroma dorsi

“…In 1986, Nakamura et al [14] demonstrated biochemically that elastin derived from EFs was only slightly different from normal elastin in its amino acid composition and the interspersed cells were considered to be fibroblasts not myofibroblasts. Fukuda et al [15] concluded that EF fibers appear not to be formed by fiber degeneration but by abnormal elastogenesis, including abnormal arrangement of microfibrils, as observed in an electron-microscopic and immunohistochemical study. Margo et al [16] reported the interesting immunohistochemical finding that most fibroblast-like cells are immunopositive for S-100 protein.…”