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Avatar universal

soy and beast cancer

it's been 4 years since my initial dagnosis. i went through chemo adria and cmf and radiation.  i have had an ongoing problem with vaginal dryness due to medical menopause.

recently i started a diet that requires the drinking of two protein shakes a day.  miraculously, my dryness compleletly cleared up but i also am noticing a tenderness in breasts similar to pms syndrome.

i suspect that this may be due to the so in the shakes.

what do you think and should i be concerned?
5 Responses
Avatar universal
Dear Herbal, There is ongoing research, which is looking at the various properties of soy, which seem to have both estrogen like and estrogen blocking features.  There is not any definitive data as to whether soy is detrimental or helpful to persons who have a history of breast cancer.  

Perhaps cutting down to one shake a day to see if that provides a balance between the relief of vaginal dryness and the breast tenderness.  Another aspect of your diet to check is your caffeine intake.  Some diet preparations may contain caffeine.  Caffeine can also contribute to breast tenderness.
Avatar universal
I was told by a breast surgeon AND a cardiac specialist that there are definite correlations being found between soy and an increased risk of breast cancer in Western women.

PLEASE do your research at PUBMED of the National Institutes of Health ... you can get the actual studies there.

I am appalled that no doctor moderates this forum and that information is so non-specific, non-referential and frankly out of date.

I am sorry that I gave this link to a friend who was just diagnosed with stage 4 breast cancer as a resource.  She methodically had mammograms and the tumor they found 4 weeks ago was BLANTANTLY apparent on her mammos -- no one told here.

her advise:  Get the pictures yourself.  You're looking for a white mass on dark gray.  She looked at an 18 month old mammo and picked it out immediately with no help from a medical professional.

Do your own research at www.cancer.org www.cancer.gov and ALWAYS BE YOUR OWN ADVOCATE -- double check everything.

Best of luck to you all.
Avatar universal
Dear Christine_nickname: You are entitled to your opinion regarding our forum.  However, you are incorrect in assuming that the issue of the correlation between soy and breast cancer is resolved.  Although we are sure your breast surgeon and cardiac specialist had only the best of intentions, this is a very controversial issue and is far from resolved.  In most cases, oncologists are the specialists who are most up-to-date on the subject.  Further, evidence that soy promotes tumor growth appears to be dependent on dose as well as estrogen-receptor status of the breast cancer (this study was published July 2001).  In addition, soy has been used in breast cancer survivors in an attempt to reduce hot flashes.  Incidentally, 37% preferred placebo, 33% preferred soy, and 31% had no preference  (This study was published July 2000).  More recent research (as yet published in abstract form but not in article form until September) demonstrates further controversy regarding this issue and supports the notion that soy may be both chemopreventive (beneficial) and estrogenic (risky) depending on dietary load.  We have attached the abstract for you to share with your physicians.

Mol Pharmacol 2001 Sep;60(3): 595-602
Estrogen Receptor alpha Mediates the Proliferative but Not the Cytotoxic Dose-Dependent Effects of Two Major Phytoestrogens on Human Breast Cancer Cells.

Maggiolini M, Bonofiglio D, Marsico S, Panno ML, Cenni B, Picard D, Ando S.

Department of Pharmaco-Biology, University of Calabria, Rende-Cosenza, Italy.

Phytoestrogens are a chemically diverse group of compounds made by plants that can have estrogenic effects in animals. Both tumorigenic and antitumorigenic effects have been reported. Although estrogens stimulate the growth of many breast tumors, there is a negative correlation between the incidence of breast cancer and the phytoestrogen-rich diet of certain Asian populations. To begin to resolve this paradox, we have analyzed the estrogenic properties of genistein and quercetin, two flavonoid phytoestrogens particularly abundant in soybeans. Trans-activation experiments with a transfected reporter gene for nuclear estrogen receptors (ER) show strong activation of the endogenous ERalpha by both phytoestrogens in two MCF7 human breast cancer cell lines. This is supported by the observation that the two phytoestrogens induce the down-regulation of ERalpha mRNA and protein levels. Using chimeric proteins consisting of the hormone binding domains of ERalpha and ERbeta fused to the Gal4 DNA binding domain, we have established that genistein and quercetin are full estrogenic agonists of both ER isoforms. Ligand binding experiments with purified ERalpha and ERbeta confirm that the two phytoestrogens are ER ligands. At concentrations that are sufficient to obtain substantial transcriptional activity, they stimulate the proliferation of two ERalpha-dependent breast cancer cell lines. At high concentrations, such as those reached with a soy-rich diet, genistein and quercetin are strong cytotoxic agents that even kill ER-independent HeLa cells. Thus, the mode of action of phytoestrogens and the balance between being risk or chemopreventive factors for breast cancer may depend on the dietary load.

PMID: 11502892 [PubMed - in process]

Avatar universal

I am an oncologist at a leading cancer center and can't tell you how many women think they should either devour as many soy products as they can in a 24 hr. period OR think they should avoid soy products like the plague!  Our center has been researching this subject also, and have yet to come up with a definitive result.  

As an aside to Christine....you might want to consider your source for information.  I wouldn't go to a cardiologist for breast cancer information...and as for surgeons, well, we all know that the only thing of interest to them is cutting! <grin>

This forum is a wonderful place for information and support and I just couldn't sit back and let Christine take "pot shots" without commenting!

Carol A
Avatar universal
I have breast cancer, dx 4 years ago.  had the lump removed, now have a lump in right breast, so now have to start working on dealing with that.  I by chance have started reading about herbs, soys,ets.  I had the strong chemo route which produced a new hair do and and excellent effective diet plan.  Lost all kinds of weight.  I have had both overies,uterus,tubes and cervix removed due to tumors.  I want to move into the herbal world to assist with modern medicines in an effort to survive.  Where should i go for advice, what books would be recommended.  I am awary of sylimarin to protect the liver from the harsheness of the chemo drugs.  there is a question of soy as a beneficial probperty, my canser is stage two ductal invasive- in the lymphnodes.  i take tamoxifen daily.  

May any one provide guidance or instruction to assist with my efforts to life.  I'm 45 and have the most beautiful grand daughter sitting on my lap as i write this note.   thanks so much for  you time.
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