CYP2C19 2 predicts substantial tamoxifen benefit in postmenopausal breast cancer patients randomized between adjuvant tamoxifen and no systemic treatment.

ABSTRACT: Estrogen catabolism is a major function of CYP2C19. The effect of CYP2C19 polymorphisms on tamoxifen sensitivity may therefore not only be mediated by a variation in tamoxifen metabolite levels but also by an effect on breast cancer risk and molecular subtype due to variation in lifelong exposure to estrogens. We determined the association between these polymorphisms and tamoxifen sensitivity in the context of a randomized trial, which allows for the discernment of prognosis from prediction. We isolated primary tumor DNA from 535 estrogen receptor-positive, stages I-III, postmenopausal breast cancer patients who had been randomized to tamoxifen (1-3 years) or no adjuvant therapy. Recurrence-free interval improvement with tamoxifen versus control was assessed according to the presence or ab

SUBMITTER: Beelen K 

PROVIDER: S-EPMC3695326 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature