Dermatofibrosarcoma protuberans

Ricardo Baroudi

Editor-in-Chief of the Brazilian Journal of Plastic Surgery

Dear Editor:

To begin with, I would like to congratulate the authors of the work entitled, “Extended resection in the treatment of dermatofibrosarcoma protuberans,” published in the Brazilian Journal of Plastic Surgery (volume 29 number 3, pages 395-403, 2014). The study stands out owing to its clarity in methodology, discussion, and conclusion, as well as study sample and excellent results. However, it would be recommended to note that the main characteristic of this type of tumor is its high rate of local recurrence after surgical excision, especially for head and neck tumors.

History of trauma as the triggering factor is described in 10% to 20% of cases. Several reports, however, describe tumors developing in scars from a previous surgery, burns, and immunization for bacillus Calmette-Guerin, and a rapid growth during pregnancy, a fact attributed to progesterone receptors in tumor tissue¹,².

The indolent behavior of dermatofibrosarcoma and its imprecise characteristics often lead to a delay in its perception by patients, thus delaying its diagnosis. However, when the lesion has progressed, the tumor is not difficult to diagnose owing to its distinctive clinical appearance (Figure 1).

Figure 1
A patient with dermatofibrosarcoma protuberans in deltoid region, which was confused for a keloid lesion because of its location in the deltoid region and the appearance of the tumor.

Dermatofibrosarcoma tumor cells stain positive for CD34 and vimentin by immunohistochemistry, but not for CD44, S-100 protein, and factor XIIIA. On the other hand, dermatofibromas stain strongly positive for CD44 and stromelysine 3 (ST3) and negative for CD34 and vimentin (Figures 2 and 3)³.

Figure 2
Immunohistochemical examination of histological sections of dermatofibrosarcoma protuberans with positive staining for CD34.

Figure 3
Immunohistochemical examination of histopathological sections of dermatofibrosarcoma protuberans with positive staining for vimentin.

The histological tumor margins are usually well beyond the macroscopic margins, because of horizontal dissemination of the tumor. Even apparently small tumors can, in fact, present distant projections interspersed in fat lobules, explaining the high rate of local recurrence. The surgical resection of the tumor must include the skin, subcutaneous tissue, and underlying fascia. Most recurrences are detected within 3 years after the primary excision, but these may appear 10 years after surgery. Owing to the high rate of local recurrence, revaluations are recommended every 6 months, with biopsies of suspected areas⁴.

The more frequent predisposing factors reported for recurrences are age older than 50 years, resection next to positive microscopic margins, fibrosarcomatotic variant of dermatofibrosarcoma, high mitotic rate, increased cellularity, and disease-free surgical margins less than 2 cm ⁵.

Finally, the only way to reduce the incidence of recurrences is by creating a wide initial excision of the tumor. However, for head and neck tumors, the margins tend to be reduced in order to preserve noble structures.

In conclusion, dermatofibrosarcoma protuberans is a locally infiltrative malignant tumor with a high recurrence rate but with a low potential for metastasis. The main differential diagnosis is with dermatofibroma. The possible presence of dermatofibrosarcoma protuberans should always be considered in cases of recurrence of injury with histopathological diagnosis of fibroma. The histopathological diagnosis of dermatofibrosarcoma protuberans may be difficult owing to the absence of nuclear atypia and low mitotic index, requiring an immunohistochemical analysis for a definitive diagnosis.

REFERÊNCIAS

• ¹
  Aoki T, Campaner AB, Ribeiro PAAG, Auge AP, Müller H, Kondo L, et al. Dermatofibrosarcoma protuberans em região inguinal: relato de caso. Rev Bras Ginecol Obstet. 2007;29(3):153-7. DOI: http://dx.doi.org/10.1590/S0100-72032007000300007
  » http://dx.doi.org/10.1590/S0100-72032007000300007
• ²
  Cakir B, Misirlioğlu A, Gideroğlu K, Aköz T. Giant fibrosarcoma arising in dermatofibrosarcoma protuberans on the scalp during pregnancy. Dermatol Surg. 2003;29(3):297-9.
• ³
  Kim HJ, Lee JY, Kim SH, Seo YJ, Lee JH, Park JK, et al. Stromelysin-3 expression in the differential diagnosis of dermatofibroma and dermatofibrosarcoma protuberans: comparison with factor XIIIa and CD34. Br J Dermatol. 2007;157(2):319-24. PMID: 17596171 DOI: http://dx.doi.org/10.1111/j.1365-2133.2007.08033.x
  » http://dx.doi.org/10.1111/j.1365-2133.2007.08033.x
• ⁴
  Kimmel Z, Ratner D, Kim JY, Wayne JD, Rademaker AW, Alam M. Peripheral excision margins for dermatofibrosarcoma protuberans: a meta-analysis of spatial data. Ann Surg Oncol. 2007;14(7):2113-20. DOI: http://dx.doi.org/10.1245/s10434-006-9233-3
  » http://dx.doi.org/10.1245/s10434-006-9233-3
• ⁵
  Macedo JLS, Barbosa GS, Rosa SC. Dermatofibrosarcoma protuberante. Rev Bras Cir Plast. 2008;23(2):138-43.

Publication Dates

• Publication in this collection
  29 May 2023
• Date of issue
  Jul-Sep 2015

History

• Received
  21 Apr 2015
• Accepted
  26 May 2015