(Figure 5.2A, B) - Common benign fibrohistiocytic tumor often on the leg
- Presents as pigmented or pink firm, dome-shaped papule with central induration, + dimple sign (dimpling of skin with inward compression of lesion)
- Histology: poorly circumscribed nodular proliferation in dermis of spindle-shaped fibroblasts with storiform pattern, hyalinized collagen at periphery of lesion (“keloidal collagen”) with fibroblasts around collagen (“collagen trapping”), epidermal hyperplasia ± flattened (“tabled”) rete ridges, ± basal layer hyperpigmentation
- Variants: atrophic DF, cellular DF, xanthomatous DF, hemosiderotic DF
| | | | | | Multiple DFs seen in LE, atopic dermatitis, and immunosuppression | | | | | |
|
| | Figure 5.2
A: Dermatofibroma
(Courtesy of Dr. Paul Getz)
B: Dermatofibroma
C: Pearly penile papules |
|
