Acral Fibrokeratoma
Steven D. Billings, MD
Key Facts
Microscopic Pathology
Dome-shaped to elongated silhouette
Epidermis is hyperkeratotic and acanthotic
Relatively hypocellular proliferation of fibroblasts
Vertically oriented thick collagen bundles
Top Differential Diagnoses
Cellular digital fibroma
More cellular than acral fibrokeratoma
Fascicles of spindled cells
Lacks vertically oriented collagen bundles
CD34 positive
Superficial acral fibromyxoma
More cellular
Loose storiform to fascicular growth pattern
Lacks vertically oriented collagen bundles
CD34 positive
Supernumerary digit
Clinically resembles acral fibrokeratoma
Disorganized nerve bundles in dermis
 Acral fibrokeratoma is a protuberant, pedunculated lesion covered by a hyperkeratotic, variably acanthotic epidermis. |
 Acral fibrokeratoma is characterized by a relatively hypocellular fibroblastic proliferation and thickened, vertically oriented collagen bundles  . |
TERMINOLOGY
Synonyms
Acquired digital fibrokeratoma
Acquired periungual fibrokeratoma
Garlic clove fibroma
Subungual fibroma of tuberous sclerosis
Definitions
Benign, dome-shaped, relatively hypocellular mesenchymal tumor that usually presents on digits
ETIOLOGY/PATHOGENESIS
Genetic Syndrome
Subset of cases associated with tuberous sclerosis
Mutation of TSC1 or TSC2
CLINICAL ISSUES
Epidemiology
Incidence
Relatively rare lesions
Age
Present in adults most commonly
Gender
Men more commonly affected
Site
