Metabolizing Tamoxifen

yoyojody
yoyojody Member Posts: 3
edited March 2014 in Breast Cancer #1
I had Estrogen Positive Breast Cancer; Stage 1; Node negative (thank god). Because I was under 50 years of age and it was infiltrating ductal with lympho-vascular invasion, it was recommended that I do chemo and radiation. I did the chemo ( 4 cycles of AC and Cytoxin), 37 radiation treatments and then started tamoxifen. fast forward 3 years...I just found out today that I have a specific gene that does not allow Tamoxifen to metabolize and I'm a little FREAKED OUT to say the least. My oncologist said since I'm still not completely in menopause, my only options are having my ovaries removed and take an aromatase inhibiter, or take Lupin shots monthly ( which shut down my ovaries and take an aromatase inhibiter. Has anyone heard of this? I am so crazed...I feel like I've lost 3 years of preventative care and now my chances of a recurrence are increased 50%. What should I do? What would you do?

Comments

  • KristyKay
    KristyKay Member Posts: 1
    #2
    tamoxifen
    How did you find out that your body wasnt metabolizing the tamoxifen....I have been taking it for about a year and reading your post concerned me.....thanks for you help.
  • Joycelouise
    Joycelouise Member Posts: 482
    #3
    KristyKay said:

    tamoxifen
    How did you find out that your body wasnt metabolizing the tamoxifen....I have been taking it for about a year and reading your post concerned me.....thanks for you help.

    I also would like to know as
    I also would like to know as I have been hearing about this also. Remember, with a cancer like yours (no nodes)chances are that they got the whole beast when they did surgery. Chances are you don't have anything left for the tamoxifin to affect one way or another. Please do not freak out too much. I know that these charts and odds can be scary sometimes. There is someone on this board who has also mentioned a problem with tamoxifin metabolizing. Hopefully she will see your post and write. love, Joyce
  • yoyojody
    yoyojody Member Posts: 3
    #4
    metabolizing Tamoxifen
    Kristy - My oncologist ran this test from a blood sample. It's a fairly new test and the information that is gained is still unclear as to what you do with the information you get. A lot of oncs won't run it but my doctor wants to know everything she can and work with what what we get. Ask your oncologist to run the DNA test for the CYP2D6 enzyme gene. If they won't, you can but the test on-line through DNADirect.com (I think that's the web site). It's like $300. I'm glad I know, I just don't know what to do at this point. Just think of all the women, all of these years, who took Tamoxifen for 5 years and never knew that they didn't get any benefit. It's scary. Well after speaking with my onc tonight I decided to stop the Tamoxifen for a month. If my side effects (hot flashes etc.) continue, we'll know that it was just little old me going through menopause and the Tamoxifen wasn't really doing anything. If the side effects stop, at least I'll know that I was getting some benefit. That's really the only way they can measure the benefit at this point. They are working on identifying the amount of benefit that one gets when they are a "poor metabolizer". I hope this helped. Good luck and be well.
  • phoenixrising
    phoenixrising Member Posts: 1,508
    #5
    yoyojody said:

    metabolizing Tamoxifen
    Kristy - My oncologist ran this test from a blood sample. It's a fairly new test and the information that is gained is still unclear as to what you do with the information you get. A lot of oncs won't run it but my doctor wants to know everything she can and work with what what we get. Ask your oncologist to run the DNA test for the CYP2D6 enzyme gene. If they won't, you can but the test on-line through DNADirect.com (I think that's the web site). It's like $300. I'm glad I know, I just don't know what to do at this point. Just think of all the women, all of these years, who took Tamoxifen for 5 years and never knew that they didn't get any benefit. It's scary. Well after speaking with my onc tonight I decided to stop the Tamoxifen for a month. If my side effects (hot flashes etc.) continue, we'll know that it was just little old me going through menopause and the Tamoxifen wasn't really doing anything. If the side effects stop, at least I'll know that I was getting some benefit. That's really the only way they can measure the benefit at this point. They are working on identifying the amount of benefit that one gets when they are a "poor metabolizer". I hope this helped. Good luck and be well.

    Hi There, I also took the
    Hi There, I also took the initiative to have my p450 2D6 checked for Tamoxifen metabolism and found out I was an intermediate metabolizer which means I only have one path instead of two paths working. I had mine done by Genelex in Washington and all I did was send in a buccal swab. (cheek)

    For those that are interested, there are four categories that are used to define how you metabolize tamoxifen. Extensive Metabolizers are normal people and do well with the standard dosage. Intermediate Metabolizers may require a lower dosage to prevent adverse drug rx's.
    Poor metabolizers are at increased risk of drug induced side effects. And Ultra-Extensive metabolizers may require an increased dosage as it's processed through their system too quickly (to achieve a steady rate).

    Many other drugs (they say 20-25%) of all our prescription drugs are processed through this pathway. Codeine and metoclopramide (Maxeran) are a couple that can be given during chemo.
    Maxeran is given for nausea. There are also many drugs that can inhibit the pathway and the most controversial right now is the SSRI antidepressants.

    I have heard that if you are experiencing side effects than it is assumed it is working. My side effects with the drug are growing and I've been on it for a little over a year. I keep thinking that it is the parent drug building up in my system. Who knows........I just get weary trying to figure all this stuff out.

    It's hard to find good info about this as it is so new and few oncs know how to deal with the results. Ask them what the side effects would be if you have only the parent drug circulating and I'm sure they wouldn't know. I have tried to find info about re-dosing based on these test results and there is no literature available. My onc couldn't help me with this and I also asked about taking 10mg/day instead of 20mg/day. There is no research so she can't say.

    You're right! What about all those women taking it faithfully for 5 years and putting up with the se and not getting any benefit. Hopefully this test will become standard procedure for all women thinking about tamoxifen.

    In the meantime I've been offered an Aromatase Inhibitor and will choose between that and decreasing my tamoxifen dosage to 10mg/day. One thing about the AI's is I don't believe they need to be metabolized. Perhaps that is what makes them seem superior. The poor metabolizers have success too.

    And for everyone's info, my onc says if you have osteoporosis you are still a candidate for the AI's. She states that research has shown that bone loss happens only with the normal and osteopenic patients. Doesn't seem to effect those who already have osteoporosis. Hmmmmm.
    First time I've heard of that but she is suppose to be a "world leader".

    Yoyojody and Kristy, do a p450 search at the top right hand side of your page and you will access the past conversations about it.

    Hope I've been helpful and good luck to you
    jan
  • yoyojody
    yoyojody Member Posts: 3
    #6
    phoenixrising said:

    Hi There, I also took the
    Hi There, I also took the initiative to have my p450 2D6 checked for Tamoxifen metabolism and found out I was an intermediate metabolizer which means I only have one path instead of two paths working. I had mine done by Genelex in Washington and all I did was send in a buccal swab. (cheek)

    For those that are interested, there are four categories that are used to define how you metabolize tamoxifen. Extensive Metabolizers are normal people and do well with the standard dosage. Intermediate Metabolizers may require a lower dosage to prevent adverse drug rx's.
    Poor metabolizers are at increased risk of drug induced side effects. And Ultra-Extensive metabolizers may require an increased dosage as it's processed through their system too quickly (to achieve a steady rate).

    Many other drugs (they say 20-25%) of all our prescription drugs are processed through this pathway. Codeine and metoclopramide (Maxeran) are a couple that can be given during chemo.
    Maxeran is given for nausea. There are also many drugs that can inhibit the pathway and the most controversial right now is the SSRI antidepressants.

    I have heard that if you are experiencing side effects than it is assumed it is working. My side effects with the drug are growing and I've been on it for a little over a year. I keep thinking that it is the parent drug building up in my system. Who knows........I just get weary trying to figure all this stuff out.

    It's hard to find good info about this as it is so new and few oncs know how to deal with the results. Ask them what the side effects would be if you have only the parent drug circulating and I'm sure they wouldn't know. I have tried to find info about re-dosing based on these test results and there is no literature available. My onc couldn't help me with this and I also asked about taking 10mg/day instead of 20mg/day. There is no research so she can't say.

    You're right! What about all those women taking it faithfully for 5 years and putting up with the se and not getting any benefit. Hopefully this test will become standard procedure for all women thinking about tamoxifen.

    In the meantime I've been offered an Aromatase Inhibitor and will choose between that and decreasing my tamoxifen dosage to 10mg/day. One thing about the AI's is I don't believe they need to be metabolized. Perhaps that is what makes them seem superior. The poor metabolizers have success too.

    And for everyone's info, my onc says if you have osteoporosis you are still a candidate for the AI's. She states that research has shown that bone loss happens only with the normal and osteopenic patients. Doesn't seem to effect those who already have osteoporosis. Hmmmmm.
    First time I've heard of that but she is suppose to be a "world leader".

    Yoyojody and Kristy, do a p450 search at the top right hand side of your page and you will access the past conversations about it.

    Hope I've been helpful and good luck to you
    jan

    Tamoxifen metabolizing
    Thanks for the info, Jan. The problem I am facing is that I haven't finished going through menopause so AI's are not an option. Unless and it's a BIG UNLESS..I have my ovaries removed or take a shot of lupron monthly to suppress my ovaries and then I can take AI's. Seems like a very big deal to me. So I spoke to my onc last night and she wants me to stop taking Tamoxifen and wait a month to see if I have the side effects I have been having for the past 2 1/2 years. If I have symptoms, then we'll know that It's just my body going thru menopause and the tamoxifen did absolutely no good. If I have no symptoms, then we'll know that I got some benefit out of it. We just don't know how much. Side effects are the only barometer they have to gauge if the meds are working. They are trying to develop a test for us "poor mets" and "inter mets" to see exactly what the % is that we are getting. That would be great. In the mean time, I'm just going to wait and see.Thanks and be well, Jody
  • Sandylmt
    Sandylmt Member Posts: 2
    #7
    yoyojody said:

    Tamoxifen metabolizing
    Thanks for the info, Jan. The problem I am facing is that I haven't finished going through menopause so AI's are not an option. Unless and it's a BIG UNLESS..I have my ovaries removed or take a shot of lupron monthly to suppress my ovaries and then I can take AI's. Seems like a very big deal to me. So I spoke to my onc last night and she wants me to stop taking Tamoxifen and wait a month to see if I have the side effects I have been having for the past 2 1/2 years. If I have symptoms, then we'll know that It's just my body going thru menopause and the tamoxifen did absolutely no good. If I have no symptoms, then we'll know that I got some benefit out of it. We just don't know how much. Side effects are the only barometer they have to gauge if the meds are working. They are trying to develop a test for us "poor mets" and "inter mets" to see exactly what the % is that we are getting. That would be great. In the mean time, I'm just going to wait and see.Thanks and be well, Jody

    Hello!
    Hello, my name is Sandy and I just joined yesterday. I joined because I too am concerned about whether my Tamoxifen is working. I should say, I'm actually a little freaked out as well. But here's the thing with me, I have had absolutely no side effects whatsoever. Not one hot flash, still get my periods and am sleeping like a log. I actually feel better. When I went in for my 3mo check-up with my oncologist and told him these things, I think I stumped him. He is baffled as to what to do with me and it is freaking me out that we are now playing this guessing game. He told me about the test but I have no idea why he wouldn't order it. I suspect it is because as you all mentioned, what would we do with the information and the 2 options I have my oncologist did not advise. It is really bothering me and I am at a loss as to what to do now and where to go. He decided I should take it for another 6mo but I hate taking pills if I don't need to. Luckily they are generic and not expensive. I am relieved to hear there are others going through this although a little freaked that I haven't heard of anyone who, like myself, have not had one single side effect. I am sure the meds aren't working so I'm really confused on where to go from here. Doesn't sound like there's much we can do other than I could demand to have the test done. Thanks for listening. Sandy
  • TKMomma
    TKMomma Member Posts: 54
    #8
    Sandylmt said:

    Hello!
    Hello, my name is Sandy and I just joined yesterday. I joined because I too am concerned about whether my Tamoxifen is working. I should say, I'm actually a little freaked out as well. But here's the thing with me, I have had absolutely no side effects whatsoever. Not one hot flash, still get my periods and am sleeping like a log. I actually feel better. When I went in for my 3mo check-up with my oncologist and told him these things, I think I stumped him. He is baffled as to what to do with me and it is freaking me out that we are now playing this guessing game. He told me about the test but I have no idea why he wouldn't order it. I suspect it is because as you all mentioned, what would we do with the information and the 2 options I have my oncologist did not advise. It is really bothering me and I am at a loss as to what to do now and where to go. He decided I should take it for another 6mo but I hate taking pills if I don't need to. Luckily they are generic and not expensive. I am relieved to hear there are others going through this although a little freaked that I haven't heard of anyone who, like myself, have not had one single side effect. I am sure the meds aren't working so I'm really confused on where to go from here. Doesn't sound like there's much we can do other than I could demand to have the test done. Thanks for listening. Sandy

    I would demand it and not
    I would demand it and not wait another six months. Never heard of this before and plan to discuss with my oncoligist next visit.
  • jphilpo
    jphilpo Member Posts: 177
    #9
    enzyme
    It's so weird that you brought this up. My insurance company just called last week to tell me that my oncologist had authorized the DNA teat to see if I am metabolizing tamoxifen. I was shocked as I had never heard of this and I thought I had heard everything! I agreed to the test and it arrived by overnight express.It is no charge to me. It consists of 2 mouth swabs on either side of my cheek. I mailed it back and we will see.

    I hope that it is working for me. I spent the worst 6 months of my life on femara and will never go back there. I have side effects from tamoxifen, but I manage them.

    I was told by the oncologist pharmacist that some women spend 5 years on tamoxifen and it does no good for them. I don't know. It just gets discouraging when you try to do everything you can to prevent a recurrence and it is not in your hands at all. I completely understand how you must feel. I never knew any of this. I too am ER positive, double mastectomy, radiation and 2 years on tamoxifen. Tryst your instincts and your doctor. Just because femora or an aromatose inhibitor won't help me, you might be fine.

    Good luck and God Bless,

    Jean
  • TraciInLA
    TraciInLA Member Posts: 1,994 Member
    #10
    jphilpo said:

    enzyme
    It's so weird that you brought this up. My insurance company just called last week to tell me that my oncologist had authorized the DNA teat to see if I am metabolizing tamoxifen. I was shocked as I had never heard of this and I thought I had heard everything! I agreed to the test and it arrived by overnight express.It is no charge to me. It consists of 2 mouth swabs on either side of my cheek. I mailed it back and we will see.

    I hope that it is working for me. I spent the worst 6 months of my life on femara and will never go back there. I have side effects from tamoxifen, but I manage them.

    I was told by the oncologist pharmacist that some women spend 5 years on tamoxifen and it does no good for them. I don't know. It just gets discouraging when you try to do everything you can to prevent a recurrence and it is not in your hands at all. I completely understand how you must feel. I never knew any of this. I too am ER positive, double mastectomy, radiation and 2 years on tamoxifen. Tryst your instincts and your doctor. Just because femora or an aromatose inhibitor won't help me, you might be fine.

    Good luck and God Bless,

    Jean

    Just a word of caution...
    Just a word of caution that this is a 3-year-old thread, so the posts from 2008 may or may not still be accurate information....Please read with care.

    For me...when I was starting Tamoxifen 2 years ago, we had a woman on this board who had tested as a poor metabolizer, so I went to my appointment ready for a fight, gonna DEMAND the test from my doctor....only to find out that he runs the test routinely for any woman starting Tamoxifen. I tested as an intermediate metabolizer, which he said was the most common result and right where he wanted me to be.

    Interestingly, mine was a blood test, not a mouth-swab test like it was for you, Jean.

    Traci

Discussion Boards