J Cutan Pathol 2006: 33: 762–763Blackwell Munksgaard. Printed in Singapore

Copyright # Blackwell Munksgaard 2006

Journal of

Cutaneous Pathology

Letter to the Editor

Cellular digital fibromas: what aboutsuperficial acral fibromyxoma?To the Editor,

We greatly enjoyed the article by Jennifer McNiffand coworkers on cellular digital fibromas.1 This isan important observation on a lesion that can easilybe misdiagnosed as dermatofibrosarcoma protuber-ans (DFSP). Thanks to their observation, we reviseda recent report on �DFSP’. The diagnosis of DFSPwas based on a 3-mm punch, but we were puzzledwhen the excision specimen showed only repairchanges with no evidence of residual tumor. This isnot the typical behavior of a DFSP. On the contrary,a complete excision guided by clinical findings oftenextends beyond the surgical margins with subtleinfiltrating strands. Reviewing our experience withsimilar cases, we had also diagnosed an essentiallyidentical case in the past as superficial acralfibromyxoma. The diagnosis in this case was basedon a full excision where the lack of deep infiltratingfeatures was an important finding. The tumor is wellcircumscribed and confined to the upper dermis(Fig. 1) and presents with a storiform patterncomposed of uniform spindle-shaped cells with wavyfeatures and no significant pleomorphism (Fig. 2).The stroma is markedly myxoid. Immunohisto-chemistry was highlighted by strong CD34 expres-sion (Fig. 3), with the lack of factor XIIIa, S100protein or EMA staining. In our opinion, the clinicaland histological presentation is remarkably similarto the cases reported in the article by McNiff.

Superficial acral fibromyxomas were first describedin 2001, with essentially the same attributes as in thecases studied by McNiff. Superficial acral fibromyx-omas were moderately circumscribed, nonencapsu-lated dermal tumors composed of spindle to stellatecells arranged in a loose storiform pattern and

Fig. 1. The tumor is well circumscribed and confined to the upper

dermis.

Fig. 2. The tumor is composed of uniform spindle-shaped cells with

wavy features and no significant pleomorphism.

Fig. 3. Immunohistochemistry was highlighted by strong CD34

expression.

762

embedded in a myxoid stroma.2 Since then, rare caseshave been reported in the dermatology literature.3–5

Awareness of this entity is important because unlesswe determine that these represent different condi-tions, we will add confusion to the nomenclature ofcutaneous mesenchymal tumors.

Joan Guitart, MDJames Ramirez, MD

William B. Laskin, MDDepartment of Dermatology,

Northwestern University Medical School,Chicago, USA

Tel: 11312 695 4174Fax: 11312 695 0664

e-mail: j-guitart@northwestern.edu

References

1. McNiff JM, Subtil A, Cowper SE, Lazova R, Glusac EJ. Cellular

digital fibromas: distinctive CD34-positive lesions that may

mimic dermatofibrosarcoma protuberans. J Cutan Pathol 2005;

32: 413.

2. Fetsch JF, Laskin WB, Miettinen M. Superficial acral fibromyx-

oma: a clinicopathologic and immunohistochemical analysis of

37 cases of a distinctive soft tissue tumor with a predilection for

the fingers and toes. Hum Pathol 2001; 32: 704.

3. Quaba O, Evans A, Al-Nafussi AA, Nassan A. Superficial acral

fibromyxoma. Br J Plast Surg 2005; 58: 561.

4. Mayerle JH, Keller RA, Krivda SJ. Superficial acral

fibromyxoma of the index finger. J Am Acad Dermatol

2004; 50: 134.

5. Kazakov DV, Mentzel T, Burg G, Kempf W. Superficial acral

fibromyxoma: report of two cases. Dermatology 2002;

205: 285.

Letter to the Editor

763