f tamoxifen (or placebo) treatment, women in the tamoxifen group experienced higher rates of deep-vein thrombosis and pulmonary embolism, but this difference disappeared after tamoxifen was stopped.
“These updated results from the IBIS-I trial provide further confirmation that tamoxifen reduces the risk of ER-positive breast cancers in high-risk women,” the authors write. “More importantly, they provide the first randomized evidence that the benefits of tamoxifen extend beyond the active treatment period, but the side effects largely do not.”
In the second study, Trevor J. Powles, Ph.D., of The Royal Marsden Hospital in London, and colleagues analyzed more than 13 years of data from 2,471 women enrolled in a clinical trial at the hospital. The women were randomly assigned to take 20 mg/day of tamoxifen or a placebo daily for 8 years. In their initial analysis in 1998, the researchers reported that there was no difference in breast cancer rates between the two groups, when using about 6 years of follow-up data.
In the new analysis with a 20 year follow-up, the researchers again found that overall invasive breast cancer rates were not statistically different (82 breast cancer cases among 1,238 women on tamoxifen, and 104 cases among 1,233 women on placebo). However, when the researchers looked specifically at ER-positive breast cancers, they found that tamoxifen reduced the risk of ER-positive breast cancer by 39 percent. This reduction occurred for the most part in the later follow-up period.
“We found that…a highly statistically significant risk reduction was found that could be attributed principally to a reduction in the risk of ER-positive breast cancers,” the authors write. “This reduced risk appears to be increasing with longer follow-up.”
In an editorial, Umberto Veronesi, M.D., of the European Institute of Oncology in Milan, Italy, and colleagues put the new results in context with other long-termPage: 1 2 3 Related medicine news :1
. Letrozole Beats Tamoxifen in Breast Cancer Therapy2
. Tamoxifen does not adversely affect the brain3
. Tamoxifen reduces breast cancer risk 4
. Tamoxifen reduces breast cancer risk 5
. Aromatase Inhibitors drug Femara after Tamoxifen therapy protects from breast cancer recurrence6
. Tamoxifen Ineffective In Presence Of Genetic Variation in Breast Cancer7
. New Drug More Effective than Tamoxifen in Preventing Breast Cancer Relapse8
. Raloxifene Better Than Tamoxifen For Breast Cancer9
. Aromatase Inhibitors Better Than Tamoxifen For Treating Receptor-Positive Early Breast Cancer10
. Study Identifies Mechanism Which May Help Tamoxifen Work Better11
. Tamoxifen Discontinuation Rates Surprisingly High