Most germline and somatic pathogenic or likely pathogenic variants found in IBC patients in this study correspond to proteins involved in DNA damage repair (BRCA1, BARD1, BRCA2, PALB2, RAD51C, MUTYH, ATM, PMS1, PMS2, MSH2, MSH6), cell cycle control (RB1, TP53, CHEK2) and apoptosis (APC, CASP8). This evidence concerns the gene RB1 and inflammatory breast carcinoma.