Controversy of the Influence of HRTs on Cancer

September 4, 2006

OBGYN.net Conference CoverageFrom 2nd Controversies in Gynecology and Obstetrics, Paris, France - September 2001

Hans van der Slikke, MD: "It's September of 2001, and we're in Paris at the 2nd Controversies Conference. Next to me is Professor Andrea Genazzani from Pisa - welcome."

Professor Andrea Genazzani, MD: "Yes, welcome. Welcome to OBGYN.net."

Hans van der Slikke, MD: "We just had a session about the controversy of the influence of hrts the hormones on cancer, and we learned that Professor Genazzani just had a special conference a few months ago about this topic. Professor Genazzani, could you please tell us something about the results of that conference you had in Pisa?"

Professor Andrea Genazzani, MD: "Yes, this was a workshop on controversial issues in climacteric medicine organized by the International Menopause Society and devoted to HRT and cancer. The conclusion of this nearly four days long meeting where we had more than eighty people coming, chosen by the most distinguished scientists on these topics, was we achieved many results at the end but I can probably give you a resume. First of all, the definition was that estrogen are not carcinogenic but they can promote replication of cells and these can stimulate the fact and that some mutagenic effects can be present and they can be more active on these cells."

Hans van der Slikke, MD: "Is this for HRT as well as for oral contraception?"

Professor Andrea Genazzani, MD: "No, this is in general, in fact, you have to believe if a woman doesn't take oral contraceptives and she has her own estrogens then this will not change so much. Concerning the problem of hormone replacement therapy and cancer, we have divided the topic in different points. They were the breast cancer effect, endometrium cancer, the ovary, and then colon cancer. Concerning the breast cancer, we have seen that certainly the theory is consistent that hormone replacement therapy done after menopause significantly raises the percentage of people affected by more or less 20% in a 5 and 10 years basis but we have seen that the total mortality does not vary significantly. This means that even though we have an increased number of cancers these cancers seem to be less aggressive and the therapy seems to be more efficient. 

In another site we have also seen that the total number of cancer in women - for 1,000 women followed from 15 to 70 years - if they are treated for 5 years the total number of cancer rose to only 2. If they are treated for 10 years, the total number rose to 6 and if they are treated for 15 years, the total number rose to 12 in total on 1,000. This means that even though this can represent a possible risk it is a reduced risk in comparison to the total benefit observed in other areas, and if this is not affecting the mortality this is strongly consistent for the fact that these kinds of tumors can be treated better in comparison to the other ones. 

Then we went to examine the effect on the endometrium and we observed that not only estrogen has to be given to post-menopausal women but also a gestagen - this give a consistent protection against endometrial cancer. We had no reduction of unexpected numbers of endometrial cancer but the increase is absolutely minimal even though it exists. Then we went to examine the effect on ovarian cancer, and ovarian cancer which is by chance a low percentage in women, there are a series of data appearing this year that slightly shows that long-term exposure to hormone replacement therapy can slightly raise the incidence of the ovarian cancer. But concerning the point that we don't yet know if the bias of the selection of population between those who are taking hormones and those who are not taking hormones this can be one of the major factors that can differentiate the two groups of treated and non-treated and for that point we need further studies. However, a very protective effect has been shown concerning the colon cancer. 

Concerning the colon cancer, which is one of the major ones for distribution cancer in women, the hormone replacement therapy gives a protection of nearly a 40% reduction. Then the total point of view of the fact of hormonal replacement therapy and cancer in general for post-menopausal women gives on one side a possible increased risk for breast and a possible increased risk for the ovary even though it's minimal with more or less no effects on the endometrium and a strong protection against colon cancer. But the woman who has to take that kind of therapy should take care of these facts and also take care of the big protection for osteoporosis and for cardiovascular disease. We had another workshop one year ago at the Royal Society of Medicine, which was organized by the International Menopause Society on HRT and cardiovascular disease. The final results were that not for secondary prevention but for primary prevention hormone replacement therapy seems to have a very protective effect in the reduction of the risk of cardiovascular disease. 

Also, the other major point was an absolutely strong and positive effect on the brain, on mood, and behavior. I think for all these characteristics we have to give to the woman all this information, we have to analyze personal risks, family risk, lifestyle, habits, and also give to them a series of suggestions to live longer but certainly not to avoid the possibility that HRT can represent something for the improvement of the quality of life and also for the protection of the woman's body and to also have a longer life."

Hans van der Slikke, MD: "Thank you very much, Professor Genazzani, for what I thought would be an interview but it happens to be a lecture, but thank you very much."

Professor Andrea Genazzani, MD: "I thank all the readers of OBGYN.net and please all take care of that program and also follow all our transmissions. Here, you will have very hot information day by day."

Hans van der Slikke, MD: "Thank you very much again."