Cellular digital fibroma is a distinctive CD34-positive benign lesion of the distal fingers and toes whose diagnosis requires correlation of the tumor’s clinical morphology and the pathologic features in order to exclude other acral tumors in the differential diagnosis such as superficial acral fibromyxoma and acquired digital fibrokeratoma |
Cellular digital fibroma presents as a slow-growing, typically asymptomatic, erythematous or flesh-colored, small (usually less than 5 mm), solitary papule that is located either on the dorsal, lateral, or ventral side of a digit or the digit’s nail fold |
Cellular digital fibroma shows a dense collagenous dermal stroma with a prominent cellular proliferation of spindle-shaped fibroblasts extending from the papillary dermis into the upper reticular dermis; the overlying epidermis shows compact orthokeratosis and acanthosis—with or without an epithelial collarette extending into the dermis and surrounding the tumor |
Cellular digital fibroma shows diffuse and strongly positive CD34 staining, positive vimentin staining, and focal positive factor XIIIa staining; they do not stain with epithelial membrane antigen (EMA), S100, desmin, muscle-specific actin, smooth muscle actin, and tryptase |
The treatment of cellular digital fibroma is conservative complete excision; however, recurrence has not been observed even after partial tumor removal |
Introduction
C | Agea (yr) | Dur (mo) | Pain | Sizeb (mm) | Sitec | CD99 | EMA | Factor XIIIa | S100 | Recurd (mo) | Ref |
---|---|---|---|---|---|---|---|---|---|---|---|
1 | 27 | 12 | Slt | 10 | FR2 | NP | NP | NP | NP | NS | 1 |
2 | 38 | 6 | None | 5 | HR2 | – | NP | NP | – | No (18) | 2 |
3 | 42 | NS | NS | NS | HR3 | NP | e | +f | e | g | 3C8 |
4 | 47 | NS | NS | NS | HR1 | NP | e | +f | e | g | 3C7 |
5 | 51 | NS | NS | NS | HLh | NP | e | +f | e | g | 3C5 |
6 | 53 | 2 | NS | 5 | FRi | NP | NP | – | – | NS | 4 |
7 | 55 | 24 | NS | NS | HR2 | +j | – | NP | – | No (18) | 5 |
8 | 56 | NS | NS | NS | HRk | NP | e | +f | e | g | 3C4 |
9 | 60 | 10 | None | 5 | HR2 | NP | – | – | – | No (18) | 6 |
10 | 61 | 18 | None | 5 | FL1 | NP | – | +l | – | No (5) | CR |
11 | 67 | NS | NS | NS | HR3 | NP | e | +f | e | g | 3C1 |
12 | 82 | NS | NS | NS | FL1 | NP | e | +f | e | g | 3C12 |
Case | Agea | Siteb | References |
---|---|---|---|
1 | 33 years | Foot, Left: 1 | 3, case 6 |
2 | 37 years | Foot, Left: 2 | 3, case 2 |
3 | 40 years | Hand, Right: 4 | 3, case 11 |
4 | 45 years | Foot, Right: 2 | 3, case 9 |
5 | 50 years | Foot, Leftc | 3, case 10 |
6 | 53 years | Hand, Right: 2 | 3, case 13 |
7 | 77 years | Hand, Left: 1 | 3, case 3 |
8 | 83 years | Hand, Right: 3 | 3, case 14 |
Discussion
History
Nomenclature
Epidemiology
Duration
Symptoms
Location
Locationa | Men | Women | Total | Total | ||||
---|---|---|---|---|---|---|---|---|
Site | Digit | Left | Right | Left | Right | Left | Right | |
Foot | 1 | 2 | – | 1 | – | 3 | – | 3 |
Foot | 2 | – | 1 | 1 | 1 | 1 | 2 | 3 |
Foot | 3 | – | – | – | – | – | – | – |
Foot | 4 | – | – | – | – | – | – | – |
Foot | 5 | – | – | – | – | – | – | – |
Foot | Other | – | 1b | 1c | – | 1 | 1 | 2 |
Total | 2 | 2 | 3 | 1 | 5 | 3 | 8 | |
Hand | 1 | – | 2 | 1 | – | 1 | 2 | 3 |
Hand | 2 | – | 2 | – | 1 | – | 3 | 3 |
Hand | 3 | – | 2 | – | 1 | – | 3 | 3 |
Hand | 4 | – | – | – | 1 | – | 1 | 1 |
Hand | 5 | – | – | – | – | – | – | – |
Hand | Other | 1c | 1d | – | – | 1 | 1 | 2 |
Total | 1 | 7 | 1 | 3 | 2 | 10 | 12 | |
Total | 3 | 9 | 4 | 4 | 7 | 13 | 20 |
Clinical Presentation
Pathology
Hematoxylin and Eosin Staining
Mucin Staining
Immunoperoxidase Staining
Cluster of Differentiation 34 (CD34)
Cluster of Differentiation 99 (CD99)
Vimentin
Factor XIIIa
Epithelial Membrane Antigen
S100
Diagnosis
Differential Diagnosis
Clinical
Feature | Cellular digital fibroma | Superficial acral fibromyxoma | Acquired digital fibrokeratoma |
---|---|---|---|
Morphology | Papule (dome-shaped) | Nodule | Papule (filiform) |
Clinical location | Side of digit | Subungual | Side of digit |
Periungual nail fold | Periungual nail fold | ||
Bony erosion | Never | Occasionally | Never |
Pathology location | Dermis | Dermis; can extend into subcutaneous fat | Dermis |
H&E | Spindled fibroblasts | Spindled fibroblasts | Fibroblasts and dense collagen vertically oriented to the overlying epidermis |
Lack stellate cells | Stellate cells in dermis | ||
Slight myxoid stroma | Marked myxoid stroma | ||
Variable dense collagen | Sparse dense collagen | ||
CD34 | Diffuse and strongly positive staining | Diffuse and strongly positive staining | Focally positive or negative |
CD99 | Positive or negativea | Usually positive | ?b |
Vimentin | Positive | Positive | Positive |
Factor XIIIa | Focally positive | Focally positive | Focally positive |
EMA | Negative | Usually positive | Negative |
S100 | Negative | Negative | Negative |