Myxoid liposarcoma with heterologous components: dedifferentiation or metaplasia? A FISH-documented and CGH-documented case report.
Heterologous differentiation in myxoid liposarcoma is a rare phenomenon. Few cases have been reported thus far, often without molecular assays, and the concept of "dedifferentiated" myxoid liposarcoma remains controversial. We describe a primary myxoid liposarcoma with chondroid and osseous components affecting the right thigh of a 27-year-old woman. We wondered whether these areas represented dedifferentiated components or simply metaplasia, and performed fluorescent in situ hybridization and array comparative genomic hybridization assays in the myxoid liposarcoma component and chondroid component. Fluorescent in situ hybridization analysis demonstrated a DDIT3 gene rearrangement in both components; array comparative genomic hybridization analysis did not detect any gain or loss of DNA regions in both components. Our results, demonstrating that both components have the same molecular alterations, suggest that heterologous components seen in some myxoid liposarcomas reflect a metaplastic phenomenon and not a real dedifferentiation phenomenon, challenging the concept of "dedifferentiated" myxoid liposarcoma.
*Department of Pathology, University Hospital §Department of Pathology, Centre Paul Strauss, Strasbourg †Department of Pathology, Institut Bergonié, Bordeaux ‡Department of Oncology, Centre Léon Bérard, Lyon, France.
Noëlle
N
Weingertner
Agnès
A
Neuville
Frédéric
F
Chibon
Isabelle
I
Ray-Coquard
Luc
L
Marcellin
Jean-Pierre
JP
Ghnassia
D000328:Adult; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D055028:Comparative Genomic Hybridization; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018208:Liposarcoma, Myxoid / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008679:Metaplasia; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D013848:Thigh / Q000473:pathology; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism
C497249:DDIT3 protein, human; D009363:Neoplasm Proteins; D051742:Transcription Factor CHOP