As compared to previous reports on Chinese early-stage breast tumors, the mutation rate of PIK3CA was lower (44 vs. 39% from our cohort) and TP53 was higher (45 vs. 79% from our cohort) in metastatic BC (10), and the gene amplification of FGFR1 was only found in metastatic TNBC (0 vs. 13.3% from our cohort) (19), suggesting the molecular distinction between early and metastatic breast tumors. Here, PIK3CA is linked to breast cancer.