Anastrozole for breast cancer prevention
Postmenopausal women were offered an alternative to Tamoxifen
Copper news based on the materials of Queen Mary University of London:
Drug cuts breast cancer cases by more than 50 per cent in high risk womenLarge-scale staged clinical trials of the drug Anastrozole, conducted by Queen Mary University of London under the auspices of Cancer Research UK, have shown that a five-year preventive course of the drug reduces the chances of developing breast cancer in postmenopausal women from the high-risk group by more than half.
The results obtained show that Anastrozole is more effective and safer than the drug Tamoxifen, which is usually used for preventive purposes. The trial report is published in The Lancet (Cuzick et al., Anastrozole for prevention of breast cancer in high-risk postmenopausal women (IBIS-II): an international, double-blind, randomized placebo-controlled trial).
"Anastrozole" belongs to the class of aromatase inhibitors – an enzyme contained in muscles and fat deposits, thanks to which, in postmenopause, androgen produced by the adrenal glands is converted into estrogen – into estrone and then into estradiol. Anastrozole, which reduces the concentration of circulating estradiol, has long been used for the therapy, but not for the prevention, of estrogen-dependent breast cancer in postmenopause.
Tamoxifen belongs to the class of selective estrogen receptor modulators (SERM), whose action is based on the ability to connect with hormonal receptors on the surface of tumor cells and block their binding to natural estrogen, thereby suppressing the stimulating effect exerted by the hormone on the tumor. Tamoxifen is usually prescribed to premenopausal women who have undergone estrogen–dependent breast cancer to minimize the risk of relapse of the disease, as well as to pre- and postmenopausal women who are at high risk as a means of prevention.
Almost four thousand postmenopausal women aged 40 to 70 years from 18 countries of the world were selected to participate in a double-blind, randomized, placebo-controlled study that lasted nine years (from 2003 to 2012), the purpose of which was to determine the degree of preventive effectiveness of a five-year course of Anastrozole. All participants were at high risk of developing estrogen–dependent breast cancer - they had either several benign, but potentially capable of degeneration, breast tumors, or a family history of breast cancer (two or more blood relatives with the disease). Half of the participants received 1 milligram of Anastrozole daily for five years, and the rest received a placebo.
As a result, after this period in the group taking Anastrozole, breast cancer developed in 2 percent (40 cases), and in the group taking placebo – in 4 percent (85 cases) of participants. At the same time, the side effects usually accompanying the use of estrogen-reducing drugs in the "anastrozole" group were relatively poorly expressed.
"The results obtained suggest that Anastrozole should become the drug of choice for the prevention of breast cancer in postmenopausal women with a high risk of the disease," said the leader of the research group, head of the Cancer Prevention Center at Queen Mary University, Professor Jack Cuzick. "This drug is more effective for this segment of patients than Tamoxifen and, most importantly, has fewer side effects."
Kazik's group intends to conduct additional studies in order to test the possibility of expanding the range of patients who could be prescribed a preventive course of Anastrozole. But, according to him, scientists are already planning to propose to the British National Institute of Health and Quality of Medical Care (National Institute for Health and Clinical Excellence, NICE) to include a five-year preventive course of "Anastrozole" for postmenopausal women with a high risk of breast cancer in the recommendations for the National Health System of Great Britain (NHS). Since June 2013, similar recommendations have been in effect in the UK for Tamoxifen.
Portal "Eternal youth" http://vechnayamolodost.ru17.12.2013