text_1: The relationship between a breast cancer patient's capacity to metabolize tamoxifen and treatment outcome is independent of the patient's genetic make-up.
text_2: Compared with extensive metabolizers, there was a significantly increased risk of recurrence for heterozygous extensive/intermediate metabolizers (time to recurrence adjusted hazard ratio [HR], 1.40; 95% confidence interval [CI], 1.04-1.90) and for poor metabolizers (time to recurrence HR, 1.90; 95% CI, 1.10-3.28).