Supporting Families with Cancer Lifestyle and Cancer Awareness Workshop 3, University of Leicester, 23 February 2013 – Tamoxifen and Breast Cancer by Dr Julian Barwell
For that so what i’m going to talk about is the latest development which came out the consultation period from the national in tubes clinical excellence guidelines series of experts dealing with inherited breast cancer susceptibility and thinking about what steps we take to actually reduce the risk of breast cancer it’s great we’ve got two members of that that
Specialist committee actually in the audience today as joyce says this is open for debate at the moment so theoretically you can go on to the national museum collections guidelines and understand that you can comment yourself if you have strong strong views on this and this is particularly frustrating today on tamoxifen and raloxifene turn to drugs which have
Been shown it was a number of studies to actually help reduce the risk of breast cancer and i’m going to talk about what that means for families living in our region on potentially and from april we will have to to say so what the most is or nearly practically audience is taken directly from that consultation to document think it’s safe to say there’s still a lot
Of unanswered questions as to how this would actually take place in reality and exactly which women may be thinking of taking tamoxifen but basically any drug has side effects really so there’s always pros and cons and when you’re dealing with people who are risk of cancer compared to people who have been diagnosed with cancer clearly that relationship is very
Different because somebody who is a highly zircon sir we’re generally talking about whether they cause of risk of cancer approaching one to two percent per year those sorts of figures when it comes to their what the guidance was looking at was looking at five and ten-year risks for women who are between the ages of 30 and 50 to start off with and the sorts of risk
That they were looking at whereby the benefit my start to outweigh the costs are looking at about three and a half percent risk of developing breast cancer over 10 years or one-point-six percent 1.66 percent over five years so in other words if you’ve got a rumor of a hunt of 90 women then you’re saying that about three per cents of them might develop breast cancer
Over that ten-year period and with regards to what that means for the women in our area we are looking at approximately a thousand women who may be eligible in a population of our size who are at this either high risk or mod requests and here we’ve got the definition as to what hi a moderate maybe so joy said that everyone in the general population now because about
Approximately on one-in-eight chance of developing breast cancer and it does depend partly on a number of factors being it hormonal factors as well as the family history let’s specifically looking at family history you start to become what we call a moderately increased risk around about the 16 1 and 5 and at the high risk between 14 1 and 3 those sorts of figures
And these are the sorts of risks figures that been suggested that the benefits might start to weigh the costs so to put that into context it’s about two to three percent of women in the general population that may be eligible for list and the aim is that people would take it for approximately five years and that would give benefited suggested over approximately
20 years so let’s say you’re a lady user 40 years of age and has been seen in the clinical genetics department has been told that they’re potentially a high risk of breast cancer because of their family history that individual would be eligible to consider taking tamoxifen as a preventative agent of five years and that would potentially reduce their risk 20 now
Rather than if anybody has had some oc’s offend in the audience but it certainly does have side effects it effectively puts women through a menopausal type symptoms so it can be associated with hot flushes and sweats can the first move disturbance libido you can have it obviously risks that people concerned about for blood clots and wound cancer so it’s certainly
Something that needs to be considered with all the facts and we’ve got a few more of them here today in regards to the actual reduction in risk it’s felt that for every thousand women who are taking it then we might see approximately twenty less tumors those sorts of figures that i won’t go into that but that’s just talked about the history of these drugs that’s
Unbelievably small on this projector so world 0 is 0 these are just taken directly from the guidance but what it’s saying is that tamoxifen should be if it’s going to be described patients should have written information and access the rich information a chance to see a specialist the people who are at high risk they will have an opportunity to be seen in clinical
Genetics to talk about this forwarded moderate risk it’s likely that conversation to be able to take place in secondary care so in our region for instance that would be probably in the glen filled with one of the breast care nurses we do have a moderately increased risk clinic for moving between the ages of 40 to 49 but for women that are outside of that age range
It’s not entirely clear yet exactly where that conversation will take place it’s not felt appropriate that that takes place in a primary care with your general practitioner a general practitioner may be the person that does the prescription but it’s not the person that what else to say yes that person should be taking the drug or not based on their family history
Now there was a question from the audience about bracco one in particular now what think about right one is that a very high portion of the tumors and individuals who have inherited an alteration in that gene tend to be hormonal negative it’s felt that the tumors that are prevented by tamoxifen which blocks the estrogen pathway as does raloxifene which is used
For women after the menopause we know about the proper one team is that they eighty percent of hormonal negative and so it’s felt likely that although brighter one carriers are at a much higher risk of cancer overall only a proportion of their risk is actually related to those hormonal tumors so although that stood a reasonable proportion i think overall for
Bradley one carriers that cost benefit analysis is going to be a lot more difficult to define so i think the take-home message is preventing it surgery is the best way of reducing risk particularly for brachle one gene carriers and certainly for bragger two carriers sum up and the people with a strong family history without a gene change tamoxifen may be helpful but
Take-home messages it reduces the risk of cancer by about a third so in the general population and properly bracketing you’re looking at a third reduction so for instance for somebody who has a seventy or eighty percent chance of developing breast cancer we might be able to take out a third of that risk so maybe twenty-five percent less risk so if you’ve got a 100
Women at risk of breast cancer eighty of which maybe go on to the best breast cancer we may be able to actually reduce that by 25 others women would not potentially group agents such as tamoxifen so that still leaves a significant amount so this is not i’m afraid a holy grail reducing or it’s down to nothing but for instance for women who don’t feel that preventive
Surgery may be helpful for them or not helpful in for that at this time then tamoxifen may actually be helpful and really what we need is some improvements in our ability to actually tell men and women wherever not any tumors are actually developing and we’ll be hearing a bit more about that hopefully so in terms of somatic evidence there’s evidence that tamoxifen
Compared to placebo which is no job at all gives a relative risk of point 65 now relative risk is compared to people that don’t take the drugs how what was the proportion of people that go on to develop cancer so point 65 means a thirty-five percent less cancer it doesn’t mean if you’ve got a hundred women at risk of cancer 35 less will develop cancer and that’s
A really important distinction between absolute risk and relative risk because remember the people who have got a family history not everyone goes on to develop a problem and goes on to develop cancer so it’s very important to be aware that relative risk is just a comparison to people that don’t change the drug so it’s mocks then is good at reduced risk of cancer
But it doesn’t reduce it completely we’ve generated or will have all of this on our website and we also will be very happy to send it to to anybody that so that once we have the ability afterwards too if you let us know we can send you the information from the talks i’m still be very happy to do that i said that’s part of our commitment too nice guidance is that
You should have the ability to look at this so we’ve got studies here looking at blood loss that’s from a bullet events wound cancer and lung cancer is actually quite common in women who have been treated with tamoxifen which is very good at reducing the risk of the currency’s for breast cancer it does have a slightly increased risk of of wound cancer cataracts
And coronary artery disease that the figure i draw your attention to is look at the number of patients involved comparing the drugs and the placebo and looking for differences so in here you’ve got one point six percent of patients going on to the bed of blood clots compared to one percent on the placebo so point 5 set 1 in 200 people who take one of these drugs
Are more likely to go on to bed of a blood clot then if they hadn’t have taken it these are all the sorts of discussions that we would have the people in clinic and the general advice would be if somebody’s had wooden cancer if somebody’s had a blood clot perhaps if it’s a very strong history of blood clotting in the family then we would be very cautious about
Prescribing tamoxifen as a preventative agency and we’ve got lots of evidence there about individual cats but i’m not going to go incident in diesel so if we go on to this one here we’ve got some ops baileygates raloxifene raloxifene may be useful for women after the menopause they will be given potentially again i’m not entirely sure they will be given the choice
Or beats a box of bed and your looks being a fake if that doesn’t work if it was some it was my wife and she was postmenopausal you know for raloxifene given a chance it’s more pricey but i think the side effect profile may well be slightly better so that’s something to find on the table if you see me after the so breast cancer in terms of the breast cancer risk
Seems to be the same one-point-seven percent sir no real difference in breast cancer rate but if you look at a wound cancer slightly higher with tamoxifen blood clots slightly higher with tamoxifen not huge differences if you look at the actual figures it was about 9,700 in each arm and you’ve got 141 against 100 it’s a huge difference if you’re one of the 41
People but if member that is over nearly 10,000 individuals but remember we’re talking about prevention these are people who are well you don’t have disease and so when you’re talking about the risks of blood clots and wound cancer we have to take this extremely seriously because these individuals and locations when you thinking about starting this thing but all
This data is available we’d be delighted to to share that and with you and there we have more more information on there the blood clots fractures as well people worry about these drugs because of the risks of osteoporosis now we know that after the menopause women lose about a two percent of their bone density every year and that that’s a bit of an issue for your
Free menopause in your fifties but a massive issue if you go through menopause in your 30s or 40s take the pet preventative surgery or if you begin one of these drugs so we’d be very careful about some thinking about osteoporosis and it’s a very important that if you’ve been treated for breast cancer or thinking about these competitive agents you do ask your doctor
About your bone density because if you got something important when you’re in the 70s and 80s more data there about some of them versus receiver i’m not going to say anymore about tamoxifen or any of these agents today but what i would say is that what would be extremely helpful is that if we could tell women not only their lifetime risk breast cancer but hopefully
In the future what’s actually happening in their body now and with that i’ll hand over to my colleague dr. jackie sure thank you much
Transcribed from video
SFWC Lifestyle and Cancer Awareness Workshop 3 – Tamoxifen and Breast Cancer By ClinicalGenetics
