A Novel Aberration Ofcol1a1-Pdgfbfusion As An Insertion In Chromosome 15 In One Case Of Dermatofibrosarcoma Protuberans Involving A Rare Location

Dermatofibrosarcoma protuberans (DFSP) is a rare sarcoma of the skin arising from the dermis. Its location is most commonly presented on the trunk of middle-aged adults and rarely on the face. The characteristic genetic aberration in the form of a reciprocal translocation t(17;22)(q21;q13) or a ring fusing theCOL1A1andPDGFBgenes is found in 90% of DFSP. We present a case of a 42-year-old man who presented with a DFSP on the left cheek with foci of myxoid-fibrosarcomatous transformation. A conventional chromosomal analysis revealed a complex karyotype without a supernumerary ring chromosome or a linear translocation t(17;22). Comparative genome hybridization and fluorescence in-situ hybridization revealed the fusion ofCOL1A1andPDGFBprobes inserted in chromosome 15. This is a unique case of DFSP characterized by a rare body location, unique histopathological features, and novel chromosomeCOL1A1-PDGFBinsertion, and may help guide future diagnostic and patient care modalities.