Patients without preoperative treatment and at least one copy of CYP2C8*3, CYP2C9*2, or CYP2C9*3 did not significantly differ with respect to age at diagnosis, invasive tumour size, axillary node status, histological grade, and ER or PR status when compared with the wild-type for each SNP. This evidence concerns the gene CYP2C9 and neoplasm.