Detection of the synovial sarcoma translocation t(X;18) (SYT;SSX) in paraffin-embedded tissues using reverse transcriptase-polymerase chain reaction: a reliable and powerful diagnostic tool for pathologists. A molecular analysis of 221 mesenchymal tumors fixed in different fixatives

Hum Pathol. 2001 Jan;32(1):105-12. doi: 10.1053/hupa.2001.21130.


Synovial sarcoma (SS) is a relatively rare sarcoma, which may be confused with several other mesenchymal and nonmesenchymal lesions. It bears the t(X;18) (SYT;SSX) translocation, which seems to be specific for this tumor type and can be detected in paraffin-embedded tissue, using reverse transcriptase-polymerase chain reaction (RT-PCR). However, the specificity and sensitivity of this detection method have rarely been examined in a large series. Using RT-PCR, we examined 250 mesenchymal and nonmesenchymal, benign and malignant, paraffin-embedded lesions for the SS t(X;18) (SYT-SSX) translocation. PCR products were obtained from 221 tumors (88.5%). There were 135 non-SS tumors, 22 biphasic, and 64 monophasic spindle/round cell SS, of which 10 were cytogenetically confirmed as t(X;18)-positive. SYT-SSX gene fusion transcripts were detected in the SS tumor category only (100% specificity), including 100% of the biphasic SS and 86% of monophasic spindle/round cell SS. Nine tumors originally diagnosed as SS were t(X;18) (SYT-SSX)-negative. Following reassessment, only 3 of these tumors showed clinicopathologic, immunohistochemical, and/or ultrastructural features consistent with that diagnosis, thus raising the overall detection sensitivity to 96%. With regard to the potential adverse effect of the fixatives used, PCR products were obtained in 100%, 91.5%, 90.5%, and 0% of tumors fixed with AFA, buffered formalin, Holland Bouin, and conventional Bouin's fluid, respectively. This study shows that the detection of the SS t(X;18) (SYT-SSX) in paraffin-embedded tissue is feasible with a 100% specificity and an overall 96% sensitivity, provided non-Bouin's fluid fixation is used.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers, Tumor
  • Chromosomes, Human, Pair 18 / genetics*
  • DNA, Complementary / genetics
  • Female
  • Fixatives
  • Humans
  • Male
  • Middle Aged
  • Neoplasms, Connective and Soft Tissue / genetics
  • Neoplasms, Connective and Soft Tissue / pathology
  • Oncogene Proteins, Fusion / genetics*
  • Paraffin Embedding
  • Pathology, Clinical
  • RNA, Neoplasm / genetics
  • Reproducibility of Results
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sarcoma, Synovial / genetics
  • Sarcoma, Synovial / pathology*
  • Translocation, Genetic*
  • X Chromosome / genetics*


  • Biomarkers, Tumor
  • DNA, Complementary
  • Fixatives
  • Oncogene Proteins, Fusion
  • RNA, Neoplasm
  • SYT-SSX fusion protein