Dermatofibrosarcoma protuberans: a clinicopathological, immunohistochemical, genetic (COL1A1-PDGFB), and therapeutic study of low-grade versus high-grade (fibrosarcomatous) tumors

J Am Acad Dermatol. 2011 Sep;65(3):564-575. doi: 10.1016/j.jaad.2010.06.020. Epub 2011 May 12.

Abstract

Background: Dermatofibrosarcoma protuberans (DFSP) is an uncommon cutaneous tumor, usually low grade, except for the fibrosarcomatous variant (DFSP-FS).

Objectives: We sought to compare the clinicopathological, immunohistochemical, genetic, and therapeutic features between DFSP and DFSP-FS.

Methods: The clinicopathological features were reviewed in 63 DFSP and 12 DFSP-FS. Immunohistochemistry and multiplex reverse transcriptase-polymerase chain reaction were carried out using formalin-fixed, paraffin-embedded tissue, using specific primers for collagen type I alpha 1 (COL1A1) and platelet-derived growth factor beta (PDGFB).

Results: DFSP-FS was associated with tumor history longer than 5 years (P = .009), tumor size greater than 4 cm (P = .001), more stages of modified Mohs micrographic surgery (P = .005), expansive subcutaneous infiltration (P = .005), muscular invasion (P = .0001), absence of CD34 staining (P = .018), p53 positivity (P = .006), and increased proliferative activity (P = .004) compared with DFSP. The COL1A1-PDGFB fusion transcript was found in 100% DFSP-FS and 72% DFSP. No association was found between the different COL1A1-PDGFB fusion transcripts and the different histologic subtypes. Wide local excision (2 cm) was performed in 47% of cases and modified Mohs micrographic surgery in 53%. After a mean follow-up of 73 months (range 21-235), 6 patients had local recurrence (5 DFSP, 1 DFSP-FS) and one died of disease (DFSP-FS). The only factor related to local recurrence was the type of surgery (17% wide local excision vs 0% modified Mohs micrographic surgery) (P = .006).

Limitations: Our study is retrospective. Prospective studies are necessary to confirm our results.

Conclusions: DFSP-FS reflects tumor progression in DFSP, with larger size, particular invasive patterns, p53 expression, and increased proliferative activity. However, as in low-grade DFSP, appropriate surgery permits a tumor-free excision. COL1A1-PDGFB is a useful tool for diagnosis of DFSP and particularly for DFSP-FS.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antigens, CD34 / analysis
  • Dermatofibrosarcoma / genetics
  • Dermatofibrosarcoma / pathology*
  • Dermatofibrosarcoma / surgery
  • Female
  • Humans
  • Immunohistochemistry
  • Ki-67 Antigen / analysis
  • Male
  • Middle Aged
  • Mohs Surgery
  • Oncogene Proteins, Fusion / analysis*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Skin Neoplasms / genetics
  • Skin Neoplasms / pathology*
  • Skin Neoplasms / surgery
  • Tumor Suppressor Protein p53 / analysis
  • Young Adult

Substances

  • Antigens, CD34
  • COLIA1-PDGFB fusion protein, human
  • Ki-67 Antigen
  • Oncogene Proteins, Fusion
  • Tumor Suppressor Protein p53