Long-term Tamoxifen Use Linked To Second Breast Cancer

{Tamoxifen 3D - photo left}

Long-term tamoxifen use linked to second breast cancer:
http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20090825/tamoxifen_risk_090825/20090825?hub=Health
From The Canadian Press, “A new study suggests long-term use of tamoxifen is linked to an increased risk of a second type of breast cancer…another rare subtype of the disease increased by more than 400 per cent.”

Adjuvant Hormonal Therapy for Breast Cancer and Risk of Hormone Receptor–Specific Subtypes of Contralateral Breast Cancer
http://cancerres.aacrjournals.org/cgi/content/abstract/0008-5472.CAN-09-1355v1
From Cancer Res 2009;69(17):6865–70, “Compared with the breast cancer risk women in the general population have, breast cancer survivors have a substantially higher risk of developing a second primary contralateral breast cancer. Adjuvant hormonal therapy reduces this risk, but preliminary data indicate that it may also increase risk of hormone receptor–negative contralateral tumors…Compared with women not treated with hormonal therapy, users of adjuvant tamoxifen for 5 years had a reduced risk of ER+ contralateral breast cancer [odds ratio, 0.4; 95% confidence interval (CI), 0.3–0.7], but a 4.4-fold (95% CI, 1.03–19.0) increased risk of ER- contralateral breast cancer. Tamoxifen use for <5>

From U.S. News (HealthBuzz):
http://health.usnews.com/articles/health/2009/08/26/health-buzz-rare-risk-of-cancer-after-taking-tamoxifen-and-other-health-news.html
“The study's lead author (Dr. Christopher Li ) told HealthDay News he does not think women should be afraid to take the drug, stating that its benefits outweigh its risks. Tamoxifen is customarily given only for five years because there's no evidence that longer-term use has additional benefits.”