Several chromosomal regions are found to be consistently amplified in human breast cancers. For two of these regions, 8p 12 and 10q26, we previously reported the amplification of genes encoding FGF receptors, FGFR1/FLG and FGFR2/BEK, in about 12% of breast tumors. The PLAT gene, encoding the tissue‐type plasminogen activator, is also located close to or within the 8p 12 region. In the present study, we show that both FGFR1 and PLAT can be amplified in breast as well as ovarian carcinomas. FGFR1 amplification was detected in 14.5% of breast and 7.8% of ovarian tumors, whereas PLAT was found to be amplified in 15.6% and 19.4% of the tumors, respectively. Each gene could be amplified independently of the other. These data raised the question of which gene is selected for amplification at 8p 12. In most cases, the levels of expression of FGFR1 and PLAT in breast tumors were comparable to their level of expression in normal mammary tissue. However, FGFR1 was expressed above the normal level in a certain number of cases. This gene could be a good candidate as “driver” of the 8p 12 amplification, but it cannot account for all complex molecular events taking place in this region. © 1993 Wiley‐Liss, Inc.