Influence of CYP2D6 polymorphism in the outcome of breast cancer patients undergoing tamoxifen adjuvant treatment.

Intratumoural Cytochrome P450 Expression in Breast Cancer: Impact on Standard of Care Treatment and New Efforts to Develop Tumour-Selective Therapies

“…Genetic variants of CYP2D6 can be classified based on the activity of the enzyme as extensive, intermediate and poor metabolisers and these genotypes have a gene-dose effect on the endoxifen concentrations in patients treated with tamoxifen [ 72 ]. In a study conducted by Blancas et al in 2018, a significantly lower disease-free survival was observed in a set of 87 patients taking adjuvant tamoxifen treatment with slow metabolisers compared to the rapid counterparts [ 73 ]; we refer the reader to in-depth reviews [ 74 , 75 ] of how the variant alleles of CYP2D6 can be used to predict the outcome in tamoxifen-treated breast cancer patients. A recent study conducted with data from Swedish breast cancer cohorts demonstrated a worse prognosis for both rapid and slow metabolisers (compared to normal), which could be due to the occurrence of adverse effects of the treatment [ 76 ].…”

Influence of metabolic profiles on the safety of drug therapy in routine care in Germany: protocol of the cohort study EMPAR

“…Therefore, due to individual differences in drug metabolism, the same dosage can lead to different drug concentrations, efficacy and safety of therapy. [13][14][15][16] In the last years, data on the influence of pharmacogenetic differences with a high degree of evidence from clinical studies and systematic meta-analyses could be used for therapeutic recommendations and Open access guidelines on pharmacogenetic tests. [17][18][19][20][21][22] Such guidelines are provided and constantly updated by the 'Clinical Pharmacogenetics Implementation Consortium' (CPIC) and the Dutch Pharmacogenetics Working Group (DPWG) established by the Royal Dutch Association for the Advancement of Pharmacy.…”