We restricted the cohort to women diagnosed with breast cancer after implementation of docetaxel in combination with cyclophosphamide and sometimes epirubicin as guideline chemotherapy in Denmark....Mortality was increased in variant carriers of GSTP1 rs1138272 (HR: 1.30, 95% CI 0.95–1.78) and CYP3A rs10273424 (HR: 1.33, 95% CI 0.98–1.81). SLCO1B1 rs2306283 (encoding OATP1B1) variant carriers had decreased recurrence (HR: 0.82, 95% CI 0.64–1.07) and mortality (HR: 0.77, 95% CI 0.60–0.98)....Docetaxel effectiveness was influenced by SNPs in GSTP1, CYP3A, and SLCO1B1 in premenopausal women with non-distant metastatic breast cancer...