PLEOMORPHIC FIBROMA OF THE SKIN, A FORM OF SCLEROTIC FIBROMA - AN IMMUNOHISTOCHEMICAL STUDY

We report anew case of pleomorphic fibroma of the skin arising on the face. The lesion was polypoid and fibrous, located on the dermis, and formed by coarse collagen bundles with sparse cells. It was also chara cterized by the presence of cellular atypia and pleomorphism without m itosis. Immunohistochemistry showed staining for vimentin and actin an d negativity for S-100, CD34, CD68, alpha-1-antichymotrypsin and alpha -1-antitrypsin antigens, supporting a myofibroblastic origin. A few is olated cells also showed granular cytoplasmic detection of factor XIII a. Although the disorder has been previously considered to be a tumour of preferential localization on the trunk or extremities, this does n ot always hold true as four of the 14 reported cases arose on the head . Pleomorphic fibroma is a benign condition and is we believe a varian t of sclerotic fibroma.