Detection of COL1A1-PDGFB fusion transcripts and PDGFB/PDGFRB mRNA expression in dermatofibrosarcoma protuberans..     ///    "In addition, the PDGFB gene amplification and PDGFB/PDGFRB mRNA levels were quantified by a real-time PCR system for the samples in which the fusion transcripts had been successfully detected. "