title: The Impact of CYP2D6 Genotyping on Tamoxifen Treatment.
abstract: Tamoxifen remains a cornerstone of treatment for patients with oestrogen-receptor-positive breast cancer. Tamoxifen efficacy depends on the biotransformation, predominantly via the cytochrome P450 2D6 (CYP2D6) isoform, to the active metabolite endoxifen. Both genetic and environmental (drug-induced) factors may alter CYP2D6 enzyme activity directly affecting the concentrations of active tamoxifen metabolites. Several studies suggest that germline genetic variants inCYP2D6influence the clinical outcomes of patients treated with adjuvant tamoxifen. Here, we review the existing data relatingCYP2D6genotypes to tamoxifen efficacy.
authors.affiliation: Department of Medical Oncology, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK. roberta.ferraldeschi@christie.nhs.uk.|Genetic Medicine, St Mary's Hospital, Manchester Academic Health Sciences Centre (MAHSC), University of Manchester, Oxford Road, Manchester, M13 9WL, UK. roberta.ferraldeschi@christie.nhs.uk.
authors.forename: Roberta
authors.initials: R
authors.lastname: Ferraldeschi
authors.affiliation: Genetic Medicine, St Mary's Hospital, Manchester Academic Health Sciences Centre (MAHSC), University of Manchester, Oxford Road, Manchester, M13 9WL, UK. william.newman@manchester.ac.uk.
authors.forename: William G
authors.initials: WG
authors.lastname: Newman
keywords: CYP2D6 genotyping; breast cancer; tamoxifen