FGFR1 and ductal breast carcinoma in situ: In summary, we have studied the amplification frequencies of HER2, C-MYC, CCND1 and FGFR1 in a large series of pure DCIS, DCIS associated with invasive carcinoma, and invasive carcinomas, to investigate the role of gene amplification in the progression of DCIS to invasive carcinoma.