title: Cryptic t(X;18), ins(6;18), and SYT-SSX2 gene fusion in a case of intraneural monophasic synovial sarcoma.
abstract: A 54-year-old male presented with a spontaneous peroneal nerve palsy and a diagnosis of monophasic synovial sarcoma (SS) was rendered by histologic examination. Cytogenetic analysis revealed a complex abnormal karyotype without evidence of the typical t(X;18)(p11;q11) associated with SS. Subsequent reverse transcriptase polymerase chain reaction analysis showed the presence of an SYT/SSX2 fusion transcript, confirming the presence of a cyptic t(X;18). In light of -X, -18 and marker chromosomes evident in the G-band karyotype, it was suspected that a cryptic chromosomal rearrangement involving the marker chromosomes would harbor an X;18 fusion. Multi-colored karytotyping (M-FISH) revealed a previously unrecognized t(X;18) and t(5;19) in the marker chromosomes as well as unrecognized ins(6;18) and t(16;20). The addition of M-FISH analysis in this case led to the identification of complex inter-chromosomal rearrangements, thus providing an accurate karyotype.
authors.affiliation: Department of Pathology and Laboratory Medicine, British Columbia Cancer Agency, BC, Vancouver, Canada. vlestou@bccancer.bc.ca
authors.forename: Valia S
authors.initials: VS
authors.lastname: Lestou
authors.forename: John X
authors.initials: JX
authors.lastname: O'Connell
authors.forename: Marc
authors.initials: M
authors.lastname: Robichaud
authors.forename: Charis
authors.initials: C
authors.lastname: Salski
authors.forename: Joan
authors.initials: J
authors.lastname: Mathers
authors.forename: John
authors.initials: J
authors.lastname: Maguire
authors.forename: Ilse
authors.initials: I
authors.lastname: Chudoba
authors.forename: Poul H B
authors.initials: PH
authors.lastname: Sorensen
authors.forename: Wan
authors.initials: W
authors.lastname: Lam
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Horsman
mesh_terms: D002869:Chromosome Aberrations; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D041321:Chromosomes, Human, X / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013584:Sarcoma, Synovial / Q000235:genetics* / Q000473:pathology; D014178:Translocation, Genetic / Q000235:genetics
chemical_list: D015514:Oncogene Proteins, Fusion; C116512:SYT-SSX fusion protein