FGFR1 Signature

The gene encoding fibroblast growth factor receptor 1 (FGFR1) amplification is associated with poor prognosis in estrogen receptor positive (ER+) breast cancer, and thus represents a potential therapeutic target. Fluorescent in situ hybridization (FISH) has been used as the gold standard methodology for detection of FGFR1 amplification, but it is a relatively long labor-intensive procedure and not efficient to process a large number of patient samples, especially formalin fixed paraffin embedded (FFPE) samples. This study sought to identify genes discriminative at the mRNA level for FGFR1 amplification and to construct a multi-gene test to facilitate efficient screening for FGFR1 amplified ER+ breast tumors. 64 Pre-Operative Letrozole and Z1031 patients found to be FGFR1 amplified by aCGH were analyzed for their gene expression patterns. This study involves one new sample and 63 previously submitted samples. After applying a quality control filter, the new and reprocessed data are linked to the Series record.