Over a 6-month period, 210 consecutive examples of dermatofibroma were enrolled in this study. Sections cut from paraffin fixed biopsy specimens were cut and stained with hematoxylin and eosin. The sections were analyzed by two dermatopathologists for the presence or absence of induction, for the type of change induced in the epidermis, and for features associated with these findings.

The types of epithelial changes above dermatofibromas were classified as presented in Table 1. The dermatofibromas were categorized into fibrohistiocytic (fibrocytes and histiocytes), fibrocytic (mostly fibrocytes, few histiocytes), and sclerotic (cell poor), these manifestations considered to be subsequent stages in the development of the lesion.