Dermatology Online Journal
Superficial acral fibromyxoma: Report of two cases and discussion of the nomenclature
- Author(s): Al-Daraji, WI
- Al-Daraji, U
- et al.
Superficial acral fibromyxoma: Report of two cases and discussion of the nomenclature1. University of Nottingham, School of Molecular Medicine, Division of pathology, UK
Al-Daraji WI MD1, Al-Daraji U2, Al-Mahmoud RMW2
Dermatology Online Journal 14 (2): 27
2. Department of medicine, Jordan University Teaching Hospital2 Amman, Jordan. firstname.lastname@example.org
We recently took an extensive review, as part of an audit, of the archives of one of the District General Hospitals in the UK and Jordan University Hospitals, and all lesions coded as myxoma, benign, NOS were retrieved blindly. Approximately 178 cases were reviewed. From these, two lesions of the new entity described by Fetsch et al (2001) with typical clinical, histological, and immunohistochemical were identified and the diagnosis of superficial acral fibromyxoma was made.
Audit has not been properly conducted by trainees in different specialities with a few exceptions. Since audit is an essential part of patient management, we conducted this study which revealed a new entity with a benign course, but with possible recurrences.
Superficial acral fibromyxoma (SAFM) is a distinct clinicopathological entity recently recognized by Fetsch et al. who presented a series of 37 cases in 2001 . Subsequently, a handful of scattered reports describing the typical histological features of SAFM were published [1-8]. The patients in the original description ranged from 14 to 75 years of age and male predominance was observed. The lesions described by Fetsch et al. were mainly observed in the fingers and palms.
We recently took an extensive review, as part of an audit, of the archives of one of the District General Hospitals in the UK and Jordan University Hospitals, and all lesions coded as myxoma, benign, NOS were retrieved blindly. Approximately 178 cases were reviewed. From these, two lesions of the new entity described by Fetsch et al.  with typical clinical, histological, and immunohistochemical were identified and the diagnosis of superficial acral fibromyxoma was made.
|Figure 1||Figure 2|
|Figure 1. Spindle to stellate cells embedded in a myxoid pattern. Note the presence of mast cells.|
Figure 2. CD34, diffuse positivity of the lesional cells
They describe the tumor contents as a spindle cell and stellate proliferation embedded in fibromyxoid-collagenous matrix together with increased blood vessels, multinucleated cells and mast cells. The immunophenotype of these lesions was CD34 diffuse or focal positivity, focal EMA positivity, and the presence of CD99, S100, HMB45, cytokeratin, SMA, and desmin.
Two cases were identified. One in a 35 year-old male who had a subungual nodule on his right big toe that was painless and present for 5 years. The second patient was a 45-year-old man who had a slightly pigmented painless mass on his right index finger present for 7 years.
|Figure 3. CD99, diffuse membranous staining of the lesional cells|
Histologically, the two cases presented as proliferation of spindle or stellate cells with a storiform and fascicular pattern embedded in a myxoid or collagenous matrix, increased number of blood vessels and mast cells in the stroma and a particular immunophenotype. The lesional cells are CD34, CD99 and EMA positive; these cells are negative for cytokeratin, smooth muscle, skeletal muscle and melanocytic markers (Figs. 1-3).
In conclusion, the diagnosis of myxoma, benign, not otherwise specified, should not be used anymore. This tumor, for example is a distinct clinicopathological entity well known to have a recurrence potential. Hence, appropriate diagnosis, complete surgical removal and close follow-up are recommended by the authors.
References1. Fetsch JF, Laskin WB, Miettinen M. Superficial acral fibromyxoma: 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; 32:704-14. PubMed
2. Abou-Nukta F, Fiedler P, Parkash V, Arons J. Superficial acral fibromyxoma of the distal phalanx of the thumb. J Hand Surg [Br] 2006; 31:619-20 PubMed.
3. Andre J, Theunis A, Richert B, de Saint-Aubain N. Superficial acral fibromyxoma: clinical and pathological features. Am J Dermatopathol 2004; 26:472-4. PubMed
4. Kazakov DV, Suster S, LeBoit PE et al. Mucinous carcinoma of the skin, primary, and secondary: a clinicopathologic study of 63 cases with emphasis on the morphologic spectrum of primary cutaneous forms: homologies with mucinous lesions in the breast. Am J Surg Pathol 2005; 29:764-82. PubMed
5. McNiff JM, Subtil A, Cowper SE et al. Cellular digital fibromas: distinctive CD34-positive lesions that may mimic dermatofibrosarcoma protuberans. J Cutan Pathol 2005; 32:413-8. PubMed
6. Meyerle JH, Keller RA, Krivda SJ. Superficial acral fibromyxoma of the index finger. J Am Acad Dermatol 2004; 50:134-6. PubMed
7. Oteo-Alvaro A, Meizoso T, Scarpellini A et al. Superficial acral fibromyxoma of the toe, with erosion of the distal phalanx. A clinical report. Arch Orthop Trauma Surg 2007. PubMed
8. Quaba O, Evans A, Al-Nafussi AA, Nassan A. Superficial acral fibromyxoma. Br J Plast Surg 2005; 58:561-4. PubMed
© 2008 Dermatology Online Journal