Visceral clear cell sarcoma of soft tissue with confirmation by EWS-ATF1 fusion detection

Ultrastruct Pathol. Jan-Feb 2006;30(1):111-8. doi: 10.1080/01913120500406400.

Abstract

Clear cell sarcoma of soft tissue (CCS-ST) is a rare malignant neoplasm characterized by a tumor-defining translocation [t(12;22) (q13;q12)], resulting in the EWS-ATF1 gene fusion. An extremely limited number of visceral CCS-ST cases have been reported in the literature. Here the authors report a visceral CCS-ST in a Hispanic adolescent male with a large infiltrative mass involving the small bowel. The tumor was evaluated by light microscopy, immunocytochemistry, electron microscopy, cytogenetics, and molecular genetics. The tumor cells were strongly positive for S-100 protein, but negative for HMB-45. Rare premelanosomes were identified only after an extensive search with electron microscopy. Cytogenetics showed a characteristic t(12;22)(q13;q12) for CCS-ST with isochromosome 18q and trisomy 22. An EWS exon 8 sense primer and an antisense ATF1 primer were employed for detection of the CCS-ST tumor-defining EWS-ATF1 translocation, using reverse transcriptase-polymerase chain reaction techniques (RT-PCR), and the fusion gene breakpoint underwent DNA sequencing. This tumor is exceptional, because it is the first visceral CCS-ST that has been confirmed by RT-PCR and DNA sequencing. This case also illustrates the necessity of a multimodal approach to tumor diagnosis, and the utility of cytogenetics and molecular pathology in confirming the diagnosis of CCS-ST and eliminating conventional metastatic or primary visceral malignant melanoma as a consideration.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Anemia, Iron-Deficiency / diagnosis
  • Biomarkers, Tumor / metabolism
  • Cytogenetic Analysis
  • DNA, Neoplasm / analysis
  • Diagnosis, Differential
  • Fatal Outcome
  • Humans
  • Intestinal Neoplasms / genetics
  • Intestinal Neoplasms / metabolism
  • Intestinal Neoplasms / pathology*
  • Male
  • Melanoma / diagnosis
  • Melanoma / secondary
  • Oncogene Proteins, Fusion / genetics*
  • Oncogene Proteins, Fusion / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sarcoma, Clear Cell / genetics
  • Sarcoma, Clear Cell / metabolism
  • Sarcoma, Clear Cell / pathology*
  • Sequence Analysis, DNA
  • Soft Tissue Neoplasms / genetics
  • Soft Tissue Neoplasms / metabolism
  • Soft Tissue Neoplasms / pathology*
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism

Substances

  • Biomarkers, Tumor
  • DNA, Neoplasm
  • EWS-ATF1 fusion protein, human
  • Oncogene Proteins, Fusion
  • Transcription Factors