A Multiplex Quantitative Reverse Transcription Polymerase Chain Reaction Assay for the Detection of KIAA1549-BRAF Fusion Transcripts in Formalin-Fixed Paraffin-Embedded Pilocytic Astrocytomas.


Service de Cytologie et d'Anatomie Pathologique, Département de Biopathologie Moléculaire et de Département de Neuropathologie, Hospices Civils de Lyon, Groupement Hospitalier Est, Lyon, France. [Email]


Genomic duplications and fusion involving BRAF and KIAA1549 that create fusion proteins with constitutive B-RAF kinase activity are a hallmark of pilocytic astrocytomas (PAs). The detection of KIAA1549-BRAF fusion transcripts is of paramount importance to classify these tumors and to identify patients who could benefit from BRAF inhibitors. In a clinical setting, the available material for molecular analysis from these pediatric tumors is often limited to formalin-fixed paraffin-embedded (FFPE) tissue. The aim of the present study was to develop a new method to detect the three most frequent KIAA1549-BRAF fusion transcripts, 15-9, 16-11, and 16-9, where numbers refer to the exons fused together, using a FFPE-compatible multiplex quantitative reverse transcription polymerase chain reaction (qRT-PCR).