tamoxifen with no brc gene or cancer present?

Artgirl,

As you mentioned, your sister was tested for the BRCA genes and she was not a carrier of a mutation in one of the two genes.  That means that they weren't able to identify the cause of her cancer.  Your sisters' cancer could be due to chance, due to environmental causes, or due to some other genes.  Since you share many of the same genes as your sister, you are considered to be at higher risk despite her BRCA test coming back normal.  

 There is a model called the "Gail model" that is used to determine your risk for breast cancer over five years and over your lifetime.  This model takes into account personal history risk factors as well as first degree relatives who developed breast cancer.  This model would have likely stated that your risk was high enough to consider taking Tamoxifen.

While you and Barry are right that Tamoxifen is for treatment of estrogen receptor positive breast cancer, your doctors and genetic counselor are correct in offering it to you as an option to reduce your risk.  You are at increased risk, based on your family history, to develop any type of breast cancer, not just estrogen receptor negative or triple negative.  It is possible to see different hormone statuses in different individuals in the same family and to see estrogen receptor positive breast cancer after menopause.

In the end, Tamoxifen is an option for you to reduce your breast cancer risk though it is not without its side effects.  Monitoring with mammo, and possibly MRI, is important no matter whether you choose to take Tamoxifen or not. 

Hi artgirl,

Just FYI, there is also HER2 neu+++ positive cancer.  Her 2 is an oncogene that causes the Her2 cells to multiply at a rapid, out of control pace.  It can be combined with ER-PR- BC, or ER+PR+ BC.   A very small number can be ER+PR- or ER-PR+ and Her2.

Until Herceptin, we Her2 girls were told we had a "poor prognosis."  Not any more.

Because I was triple+++ (ER/PR/HER 2+) I had Herceptin, took Tamoxifen for 2 1/2 years, and now I am on Femara. 

It was a shock to me when I was diganosed at age 48 - no BC in the family, I exercised and ate well However,. I did have big, dense breasts - After a clean mammo and breast ultrasound in July 2006, I went in for a breast reduction in Oct. 2006 - my PS found the tumour.  Go figure!

My daughters are now 24 and 21 - they will start having mammos age 30, as far as I am concerned, also will check for breast density and demand MRIs if needed.  MRIs are the only useful too to catch BC in dense breasted women, as far as I am concerned. Dense breasted woemn are 4 - 6 x more likely to develop BC than those without dense breasts - confirmed by a big study at Princess Margaret Hospical in Toronto, Canada in January 2007 (right after my diagnosis, how fitting)

 Will also def. have the docs discuss the Tamoxifen option with my girls, when the time comes. 

Artgirl,

As Caya mentioned, there are more subtypes of breast cancer than estrogen receptor positive, triple negative, and inflammatory.  DICS, LCIS, invasive ductal carcinoma, invasive lobular carcinoma, and other more rare subtypes.  Of which, can be divided on hormone status, including estrogen receptor, progesterone receptor, and HER-2 (when those three are all negative, that is what is referred to as a triple negative breast cancer).

Absolutely there are other risk factors out there.  There are other genes, other environmental factors, countless factors of which nothing is known.  Most of what is talked about when it comes to risk is for what there have multiple, scientific studies published with thousands of women being studied. 

My response to your post was aimed at attempting to answer the question of whether Tamoxifen would be useful in lower your breast cancer risk.  In the end, it is your decision whether you choose to take it.  I wish you luck in making that decision and hope that you seek out all the sources of information you need in order to make it.