Extended Duration of Tamoxifen Therapy Enhances Breast Cancer Survival — Physician’s First Watch
Extended Duration of Tamoxifen Therapy Enhances Breast Cancer Survival
Ten years of adjuvant tamoxifen therapy in women with estrogen receptor–positive breast cancer is associated with lower rates of recurrence and breast cancer mortality than 5 years of treatment, according to a Lancet article.
Researchers followed outcomes in some 6800 women with receptor-positive disease who'd completed 5 years of tamoxifen therapy, half of whom were allocated to 5 additional years of treatment.
Recurrences and breast cancer mortality were both significantly lower among those on continued therapy, with reductions being even more pronounced after 9 years. During years 5–14, mortality was 12.2% for those allocated to continue treatment versus 15.0% for controls (absolute mortality reduction, 2.8%). The incidence of pulmonary embolism (but not of death from it) was higher in the continued-treatment group, and the risk of endometrial cancer was also higher with longer treatment, including an absolute increase in mortality risk of 0.2%.
A commentator writes that confirmation of these results by meta-analysis with other tamoxifen trials "should herald a change of practice."