To examine the potential impact of low-frequency CDMs in breast carcinogenesis and targeted therapeutics, in previous work, we used ACB-PCR to quantify five hotspot CDMs (PIK3CA H1047R, KRAS G12D, KRAS G12V, HRAS G12D, and BRAF V600E) in human breast invasive ductal carcinomas (IDCs; [7]), and six hotspot CDMs (PIK3CA H1047R, PIK3CA E545K, KRAS G12D, KRAS G12V, HRAS G12D, and BRAF V600E) in the normal human breast [7,11]. This evidence concerns the gene PIK3CA and invasive ductal breast carcinoma.