IDF Flashcards
Infantile digital fibroma (IDF)
IDF aka?
Inclusion body fibromatosis
Recurring digital fibrous tumors of childhood
IDF definition
Rare, benign, fibromatous tumors most commonly located on the dorsolateral aspects of fingers and toes
When do IDFs develop?
Usually –> 1st year of life
1/3 cases –> at birth
Rarely –> adulthood
IDF natural course
Start growing slowly –> rapid growth over 10-14 months –> spontaneous regression within 2-3 y
Can reach sizes between 3 - 35 mm
IDF classical appearance
Nodules: single-multiple, smooth, firm, skin-colored to pink on dorsolateral aspects finger/toes, typically sparing thumbs and great toes
IDF Histopathology
Proliferations of spindle shaped myofibroblasts + collagen bundles within the dermis
Eosinophilic inclusions in a perinuclear fashion within myofibroblast cytoplasm (Masson’s trichrome stains them RED, phosphotungstic acidhematoxylin (PTAH) –> PURPLE
IDF Differential Dx
- Periungual fibromas
- Supernumerary digits
- Acral fibrokeratomas
Periungual fibromas?
Skin-colored to pink papules from the proximal nail fold
Pressure on nail matrix –> longitudinal groove in nail plate
Solitary or associated with: Von Recklinghausen disease or Tuberous Sclerosis (Koenen tumors)
Supernumerary digits?
Soft tissue growths with NO skeletal component
Fleshy or verrucous like papules, or larger pedunculated nodules
Often at birth, bilateral, MC location: lateral aspect 5th finger
Acral fibrokeratomas?
Relatively rare, benign skin growths
Skin-colored to pink, faintly keratotic papulonodules
Usually solitary, on fingers/toes of middle age adults, also on palms/soles
IDF management
No consensus yet
Surgical excision as an option, but recurrence is common (rec rate 61-74%). Reserved for symptomatic cases –> pain/functional impairment)
Nonsurgical options: topical steroids, intralesional Triamcinolone, intralesional 5-fluororacil (5-FU)
