FGFR3 and neoplasm: No copy number gains were detected for FGF3, FGF4, FGFR1, FGFR2, FGFR3, or FGFR4. To investigate whether an FGF19 copy number gain was associated with a response to sorafenib, we analyzed additional tumor specimens from 35 patients who did not respond to sorafenib.