The cancers in which FGFR gene amplifications are most frequent include squamous cell lung cancer (FGFR1), head and neck squamous cell cancer (FGFR1), bladder (transitional cell) cancer (FGFR1), endometrial cancer (FGFR1), gastric adenocarcinoma (FGFR2), breast adenocarcinoma (FGFR1), and prostate adenocarcinoma (FGFR1). Here, FGFR1 is linked to breast adenocarcinoma.