The most frequent genomic variants in both DCIS and IBC were noted to be PIK3CA, TP53, KMT2C, MAP3K1, GATA3 and SF3B1, with KMT2C being more frequent in DCIS and TP53 and MAP3K1 more frequent in IBC, though the numbers are too small for definitive conclusions. This evidence concerns the gene PIK3CA and ductal breast carcinoma in situ.