Tamoxifen approved for preventive treatment in Britain
Why does the European Union - with the exception of one of its Member States - ban the use of tamoxifen for preventive purposes?
Dr. Suzette Delaloge: "Tamoxifen has been the subject of five large randomized, pure prevention trials in middle- to high-risk women. This treatment reduced the risk of breast cancer by 25-50%, the latter referring to a trial conducted by the United States.
European trials were negative in two cases, with a third concluding a 33% reduction in risk. In view of these results, the European Union has always considered that the benefit-risk ratio was not in favour of the prescription of tamoxifen."
What are the specific risks identified for tamoxifen?
Dr. Suzette Delaloge: "Tamoxifen leads to an over-risk of deep vein thrombosis and pulmonary embolism in the order of 2-3% over 5 years. This is infinitely superior to the 3rd generation pills that are currently being debated! It also causes significant cardiovascular over-risk (infarction and stroke), as well as endometrial cancer.
"Tamoxifen also causes weight gain. For all these reasons, it seems very difficult to go back on banning tamoxifen for preventive purposes, if not in the case of women at very high risk of cancer. Yet, even in this case, there is no clear demonstration of benefit to date, as published trials do not distinguish risk groups."
Why do the positions of the United States and Great Britain differ so significantly from those of the European Union on this issue?
Dr. Suzette Delaloge: "In Britain, there is a strong investment in screening and prevention, with less involvement in cancer therapeutics: many drugs are allowed in France or Germany, which are not allowed across the Channel.
"It is also important to remember that the admissibility by the population of prevention practices is very different between our countries!
"For example, in France, a randomized study unique in the world has been open for 4 years (LIBER) [to study the effects of letrozole for women with mutations increasing their susceptibility to breast cancer]: this study will stop in months having included less than a third of the women originally planned! The refusal rate is enormous as we address the most risky populations possible!"
So a reassessment of tamoxifen is not on the agenda on this side of the Channel?
Dr. Suzette Delaloge: "I can't see France coming back to this issue without additional data and in the appalling context of the pills. More generally, in the absence of new data, there is no reason for the European Union to change its recommendations."
Dr. Suzette Delaloge: "Tamoxifen has been the subject of five large randomized, pure prevention trials in middle- to high-risk women. This treatment reduced the risk of breast cancer by 25-50%, the latter referring to a trial conducted by the United States.
European trials were negative in two cases, with a third concluding a 33% reduction in risk. In view of these results, the European Union has always considered that the benefit-risk ratio was not in favour of the prescription of tamoxifen."
What are the specific risks identified for tamoxifen?
Dr. Suzette Delaloge: "Tamoxifen leads to an over-risk of deep vein thrombosis and pulmonary embolism in the order of 2-3% over 5 years. This is infinitely superior to the 3rd generation pills that are currently being debated! It also causes significant cardiovascular over-risk (infarction and stroke), as well as endometrial cancer.
"Tamoxifen also causes weight gain. For all these reasons, it seems very difficult to go back on banning tamoxifen for preventive purposes, if not in the case of women at very high risk of cancer. Yet, even in this case, there is no clear demonstration of benefit to date, as published trials do not distinguish risk groups."
Why do the positions of the United States and Great Britain differ so significantly from those of the European Union on this issue?
Dr. Suzette Delaloge: "In Britain, there is a strong investment in screening and prevention, with less involvement in cancer therapeutics: many drugs are allowed in France or Germany, which are not allowed across the Channel.
"It is also important to remember that the admissibility by the population of prevention practices is very different between our countries!
"For example, in France, a randomized study unique in the world has been open for 4 years (LIBER) [to study the effects of letrozole for women with mutations increasing their susceptibility to breast cancer]: this study will stop in months having included less than a third of the women originally planned! The refusal rate is enormous as we address the most risky populations possible!"
So a reassessment of tamoxifen is not on the agenda on this side of the Channel?
Dr. Suzette Delaloge: "I can't see France coming back to this issue without additional data and in the appalling context of the pills. More generally, in the absence of new data, there is no reason for the European Union to change its recommendations."