Basal cell carcinoma overlying long-standing dermatofibromas

Invasive Basal Cell Carcinoma with Metaplastic Bone Formation Associated with a Long‐Standing Dermatofibroma

“…Invasive basal cell carcinoma arising in a long-standing dermatofibroma is a rare event. It has been reported by Detlef et al (1975) and confirmed later by Bryant (1977), as well as by Schoenfeld (1964). Others have reported osteoid formation within dermatofibromas; however, we believe this is the first report of botli entities occurring within a dermatofibroma.…”

Lentiginous Melanocytic Hyperplasia Overlying Dermatofibroma

“…Some authors have considered these features to be a result of regressed hair follicles pushed up against the overlying epidermis by the dermal cellular proliferation (4), whereas others interpret the epidermal changes as a reaction to influences from the underlying fibrohistiocytic proliferation (2,5). At times, this basaloid proliferation may be so extensive that it resembles superficial basal cell carcinoma (6), and in rare instances, invasive nodular basal cell carcinoma develops overlying a dermatofibroma (7,8). Finally, coincidental findings in the epidermis overlying dermatofibromas include focal acantholytic dyskeratosis (9), epidermolytic hyperkeratosis, pale cell acanthoma-like changes (2), squamous cell carcinoma in situ (10), and plate-like sebaceous hyperplasia (11).…”

Adnexal displacement and regression in association with histiocytoma (dermatofibroma)

“…All the literature reviewed, including the references cited (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14), discusses only "induction" of changes in the epidermis overlying histiocytomas. This "induction" is attributed to some chemicals or other "organizers" presumably secreted, excreted or produced by histiocytomas, which affect the epidermis, resulting in production of hair follicle-like tissue.…”