Joseph NBH, MD, FACOG, AACS, AACG

Tamoxifen and Breast Cancer. In our Austin and San Antonio clinics, I have seen many clients who have been placed on the anti-estrogen drug, Tamoxifen, after being diagnosed with breast cancer. The reason this drug is prescribed after breast cancer is to decrease the receptor response to estrogen both in the remaining breast tissue and in metastasis (spreading of cancer). It is used in premenopausal women to prevent estrogen from binding to the receptors in the nucleus of the cells so the estrogen molecule doesn’t theoretically increase the growth of the cancer.  It does not decrease the production of estrogen from the ovaries or adrenal glands.

I have seen several clients that were miserable on Tamoxifen, suffering from hot flashes, nausea, thinning hair, poor sleep and weight gain, particularly increased belly fat. They all had normal estrogen levels but all had signs and symptoms of progesterone deficiency.

Alternative to Tamoxifen? Blocking estrogen receptor sites may not be the best solution to preventing breast cancer or preventing a recurrence of breast cancer. This paper will explain the benefits of bioidentical progesterone and will describe other risks factors of breast cancer that can be addressed by all women with the goal of prevention.

What is Tamoxifen? Nolvadex (tamoxifen citrate) is a drug that is used to block estrogen by blocking estrogen receptors in the breast cells. The drug companies state that it blocks breast cancer cell growth since breast cancer cells need estrogen to grow. Tamoxifen is the “usual endocrine (anti-estrogen) therapy for hormone receptor-positive breast cancer in pre-menopausal women”, and is also used in post-menopausal women although aromatase inhibitors are frequently used. It is typically used by conventional medicine “to treat breast cancer that has spread to other parts of the body (metastatic breast cancer), to treat breast cancer in certain patients after surgery and radiation therapy, and to reduce the chances of breast cancer in high-risk patients.”

The most common side effects include hot flashes, nausea, leg cramps, hair thinning, or headache. A loss of sexual ability/interest may occur in men. Other less common side effects may also occur. Yes, men can get breast cancer.

Addressing the CAUSES of breast cancer. If you want to prevent breast cancer or prevent recurrence maybe we should address the cause and direct our attention to this instead of just focusing on pharmaceutical drugs.  I have listed below many of the causes of breast cancer. Each of these should be considered early in life to help prevent it. They should also be addressed in trying to prevent recurrence.

  • Synthetic Hormone Replacement Therapy (HRT) using progestins such as Provera used in Prempro. This synthetic drugs was used in the Women’s Health Initiative (WHI) study, that established this drug as increasing the risk of breast cancer). See www.naturalbiohealth.com (blog: “Clarity on hormones and cancer.”)
  • Pesticides ( most are Xenoestrogens that induce estrogen dominance)
  • Obesity (estrogen dominant, progesterone deficiency)
  • Diet (Isoflavins: such as soy, estrogen dominance)
  • Alcohol (reduces immune system, alcohol will reduce the white blood cell count in the body)
  • Tobacco (Smoking weakens the immune system by depressing antibodies and cells that are in the body to protect against foreign invaders)
  • Bad oral hygiene and dehydration (decreases your immune system)
  • Lack of exercise (decrease in your immune system and so does too much exercise)
  • Stress (decrease immune system)
  • Lack of sleep (decreases your immune system)
  • Progesterone deficient /estrogen dominance conditions: PMS,  PCOS,  infertility, endometriosis,      luteal phase defects

One significant correlation is between the lack of sufficient amounts of progesterone and the interaction with stress that increases cortisol. Increased cortisol decreases one’s immune system which in turn increases the chances of any cancer occurring. Biodentical progesterone has been shown in many studies to decrease the risk of breast cancer.

So what should you do to prevent breast cancer initially or to prevent its recurrence after having had breast cancer? This is a complicated area as the cancer can have estrogen or progesterone receptors or not have either one. It may be positive for HER2 or many other genetic risk factors that have been a concern. HER2 is  breast cancer that tests positive for a protein called human epidermal growth factor receptor which promotes the growth of cancer cells. This type of breast cancer is less responsive to hormone treatment.

This now brings up an important point that many physicians have yet to accept yet many studies support. Estrogen is not the cause of breast cancer!  Even in the WHI study, the women who took estrogen alone had less breast cancer than those that took nothing by 30% (the placebo group). It has also been shown in several studies that long term estrogen, unopposed by not taking progesterone, may slightly increase the risk of breast cancer.  Since Tamoxifen has about 40% effectiveness in most studies, then one has to weigh the symptoms caused by the Tamoxifen versus the very little risk in not taking it and addressing all the suspected causes of breast cancer listed above.

I am not suggesting that patients with breast cancer not take Tamoxifen especially those where a lumpectomy has been performed may not need Tamoxifen. Taking progesterone both pre and post menopause, eliminating all the potential causes listed above, and improving the immune system are the most important steps women can take to decrease their risk of breast cancer.

Five year survival rate. It is generally accepted that after five years it is assumed that the cancer is cured (if not present after five years with no recurrence). After this five years period, I have no qualms in treating with progesterone and estrogen and not having my clients take Tamoxifen or aromatase inhibitors such as Arimidex assuming they are also addressing the other “potential causes” listed above.

There have been several manuscripts written to back up this claim that there is no distinct risk in taking estrogen in breast cancer survivors. These studies concluded  that for these selected patients, estrogen replacement therapy (ERT) relieved estrogen deficiency symptoms and did not increase the rate or time to an ipsilateral  recurrence/new primary, contralateral new primary, local-regional recurrence, or systemic metastases. Decker DA, Pettinga JE, VanderVelde N, et al. Estrogen replacement therapy in breast cancer survivors: a matched-controlled series. Menopause. 2003 Jul-Aug;10(4):277-85.

Progesterone – the science. The European J. Cancer Preview 2002 Oct. 11(5):481-8, stated that “growth inhibition of human breast cancer cells by progesterone is due to P13-kinace/AKT pathway causing apoptosis (death) of breast cancer cells.” Furthermore they stated that progesterone was shown to inhibit proliferation of normal breast epithelial cells as well as breast cancer cells.

Even a patient who has had a lumpectomy without positive lymph nodes should be able to be treated at any time with estrogen and progesterone, whether in surgical menopause or natural menopause. However, this would be met with significant criticism by many (not all) oncologists.  Unfortunately many of the oncologists do not consider the symptoms of their patients as being worthy of treatment. On the contrary, the patient may want to have estrogen therapy rather than endure their symptoms.

By eliminating all the factors that might be responsible for breast cancer, taking cyclic progesterone and increasing the immune system, the chances of recurrent breast cancer would be small and patients can live a happy and symptom free life.

Disclaimer: Not all of the information in this blog have scientific scholarly articles to back the claims. Nevertheless, the information has been taken from reputable sources and is believed to be entirely factual.

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