Dr. Weyrich's Naturopathic Functional Medicine Notebook is a collection of information on topics of interest to Dr. Weyrich that may be of interest to the world wide audience. Due to limitations of time, not all information that Dr. Weyrich knows or would like to further research is published here. Dr. Weyrich welcomes financial contributions to support specific research topics, as well as copies of non-free access journal articles for him to review on a topic. Constructive criticism is also welcome.

Overview of Breast and Prostate Cancer

Breast Cancer and Prostate Cancer appear to be different manifestations of the same disease process, and therefore have similar etiology, prevention, and treatment options. This web page considers both.

Dr. Weyrich is not an expert in the treatment of cancer, but does offer supportive therapies to reduce pain and nausea, mitigate the side effects, and to generally boost the immune system.

Please see Cancer Overview for general information that is common to all forms of cancer.

Complimentary and alternative treatments for breast cancer and prostate cancer that are considered below include:

  • Low Dose Naltrexone

Etiology of Breast and Prostate Cancer

[Fournier2008] presents evidence that coadministration of bio-identical estrogen and progesterone does not increase the risk of invasive breast cancer, whereas administration of unopposed estrogen or non-bioidentical progestins (e.g. Provera™ = medroxyprogesterone acetate = MPA) does significantly increase the risk of breast cancer, as previously reported by the Women's Health Initiative (WHI) study [Beck2012]. Numerous other studies support the relative safety of bio-identical hormones given in physiological doses, compared with patented non-bio-identical pharmaceutical "frankenhormones": [Holtorf2009], [Moskowitz2006], [Birrell2007]. In addition, multiple studies show that use of oral contraceptives (containing non-bio-identical hormones) are linked with higher risk of breast cancer [Collaborative_Group1996]; in particular, the progestin Levonorgestrel appears to be especially problematic [Hunter2010]. This issue has also been discussed in the popular press: [Somers2006], [Somers2009], [Somers2012], [Lee2002].

Based on a study of three castrated patients with advanced carcinoma of the prostate gland, [Huggins1941] made the sweeping generalization that "giving testosterone to a man with prostate cancer is like adding oil to a fire." Subsequent studies of rats by [Noble1977] and humans [Fowler1981] reinforced the notion that testosterone promotes prostate cancer. Although Huggins was awarded a Nobel Prize for his work, and his theory has long been taught in medical schools, it has recently been shown to be almost diametrically false. In particular, Huggins' model fails to account for the role of estrogen, dihydrotestosterone (DHT), or hormone receptors in the promotion of prostate cancer.

More recently, [Morgentaler2008] has pointed out that prostate cancer is more prevalent in men with low testosterone, and that in most cases, supplementing with testosterone is actually safe and beneficial [Morgentaler2011], [Szmulewitz2009], [Morris2009], [Isaacs2012].

As will be discussed below, testosterone itself is protective; however, its metabolites estradiol (E2) and dihydrotestosterone (DHT) are the hormones actually responsible for initiating breast and prostate cancer. [Friedman2013] makes the case (see below) that without both E2 and DHT, initiation of breast or prostate cancer is not possible, and that lowering local E2 and DHT levels reduces the risk of these cancers.

It is important to distinguish between systemic levels of E2 and testosterone arising from bio-identical hormone replacement therapy (and measured in blood, urine, or saliva), versus the cancer-forming high local levels of E2 and DHT arising from excessive conversion of testosterone to E2 or DHT inside the breast or prostate tissue.

[Friedman2013] further points out that in addition to high local levels of E2 and DHT, these hormones must interact with hormone receptors in the breast and prostate named Estrogen-Receptor-Alpha (ER-A) and Membrane-bound Androgen Receptor (mAR), respectively, in order to induce cancer, as described further below.

Apoptosis (also known as "programmed cell death") is a process that protects the body from defective or old cells, and is triggered by the immune system when a cell appears to be problematic. Cellular apoptosis is modulated by the balance between competing pairs of hormone receptors, which control expression of the tumorgenic protein bcl-2 versus the anti-tumor protein p53, as discussed below [Friedman2007]. Bcl-2 is a key protein involved in the control of apoptosis, which is in turn regulated by opposing pairs of cellular hormone receptors [Kandouz1996]:

  • Estrogen-receptor-alpha (ER-A) vs estrogen-receptor-beta (ER-B)
  • Progesterone-receptor-alpha (PR-A) vs progesterone-receptor-beta (PR-B)
  • Membrane androgen receptor (mAR) vs intracellular androgen receptor (iAR)

In each of these pairs of hormone receptors, the first receptor increases expression of the tumorgenic protein bcl-2, which acts to protect the cell against normal apoptosis, thus promoting cancer. In addition, mAR decreases the production of the protective protein AS3, while iAR increases the production of the protective protein AS3 [Friedman2013, pg 60].


It is useful to compare the relative affinities of the three main types of estrogen found in humans: estrone (E1), estradiol (E2), and estriol (E3) [Friedman2013]:

Relative binding strengths of estrogen receptors for different estrogens
Receptor Estrone Estradiol Estriol
ER-A 0.1 1.0 0.11
ER-B 0.02 1.0 0.35

As we see above [Zhu2006], [Friedman2007]:

  • E1 has an affinity for ER-A that is 5 times greater than for ER-B, and thus promotes tumor development.
  • E2 has an equal affinity for ER-A and ER-B, and promotes tumor development when ER-A predominates.
  • E3 has an affinity for ER-B that is 3.5 times greater than for ER-A, and therefore is protective.
  • However, E3 binds to ER-B only 35% as strongly as E2 does, so maximum protection provided by E3 requires that E2 levels be low.

ER-B is also beneficial by reducing inflammation that is often seen accompanying both benign prostate hypertrophy (BPH) and prostate cancer [Risbridger2007], which suggests that inflammation is not a cause of prostate cancer, but rather an effect (marker) of low ER-B activity [ORWJr].

It is not clear [to Dr. Weyrich] whether ER-A itself promotes production of the anti-apoptotic protein bcl-2, or whether either the homodimer formed by two ER-A receptors, or the heterodimer formed by one ER-A combining with one ER-B is the culprit. In any case, high levels of ER-A promote formation of both the homodimer and the heterodimer, and high levels of estradiol promote simultaneous activation of both receptor regions in either the homodimer or the heterodimer [Friedman2013, pg 48]. [Ricke2008] has shown that ER-A [ORWJr: or its homodimer or heterodimer] is necessary for the formation of prostate cancer, which Dr. Weyrich considers to draw attention to ER-A, with the discussion of its homodimers and heterodimers being an interesting detail.

[Lofgren2006] has shown that in normal breast tissue, the activity of ER-A and ER-B are equal, and on balance does not promote breast cancer. However, once cancer has been initiated, natural selection tends to increase the density of ER-A relative to ER-B, since the more ER-A and the less ER-B a cell has, the more bc-2 is produced, and the greater protection the cell has against apoptosis [Friedman2013, pg 51].

There is also a third kind of estrogen receptor, which is bound to the cell membrane (mER). Like ER-A, it promotes production of the anti-apoptotic protein bcl-2 (at least in the case of breast cancer [Friedman2007]; it has not been studied in relation to prostate cancer, but Dr. Weyrich expects a similar action in the case of prostate cancer.

Based on the above, [Friedman2013] presents compelling evidence regarding the cause of prostate and breast cancer, and a clear model, The Hormone Receptor Model, for both preventing and treating both these cancers, which are primarily driven by hormonal imbalances, especially excess local tissue (not systemic serum) levels of estradiol on pro-carcinogenic estrogen-receptor-alpha (ER-A) [Bonkhoff2008]. [Friedman2013, pg 81] lists five factors are necessary to initiate prostate cancer: testosterone, dihydrotestosterone, estradiol, intracellular androgen receptor, and estrogen receptor-alpha. Dr. Weyrich notes, however, that evidence presented by Friedman exonerates testosterone as a direct causative agent - if the conversion of testosterone to dihydrotestosterone and estradiol is blocked (e.g. by 5-alpha reductase and aromatase inhibitors, respectively) then testosterone is NOT sufficient to initiate prostate cancer - see below.

Note that the enzyme aromatase converts testosterone into estradiol, and 5-alpha reductase converts testosterone to DHT, so inappropriate testosterone supplementation can indirectly promote both prostate and breast cancer (by increasing telomere length and thus preventing apoptosis of tumorgenic cells), if aromatase activity is not controlled [Friedman2007]. Support for this theory comes from a study in mice that shows that in the absence of ER-A, testosterone cannot induce cancer [Ricke2008].


PR-B is beneficial, since it up-regulates Go to p53p53, which stops cancer growth [Lee2002] by at least three different mechanisms: promoting apoptosis of defective cells, assisting in DNA repair, and inhibiting angiogenesis [Friedman2013, pg 88].

There are also two membrane progesterone receptors: mPR-5alpha and mPR-4. mPR-5alpha binds to 5alpha-pregnanes ("bad progesterone") that is formed by the action of 5alpha-reductase, and promotes cancer growth. mPR-4 binds 4-pregnenes ("good progesterone") and inhibits cancer growth in breast tissue [Wiebe2000]. These receptors have not been studied in relation to prostate cancer, but Dr. Weyrich expects a similar action in the case of prostate cancer.

The BRCA-1 and BRCA-2 genetic mutations disable the protective function of the PR-B, leaving the tumorgenic PR-A unopposed reign. In persons possessing the BRCA-1 or BRCA-2 genetic mutations, progesterone supplementation is likely to promote prostate and/or breast cancer [Friedman2007].


Cellular apoptosis is also modulated by the balance between intracellular androgen receptor (iAR) and membrane androgen receptor (mAR). iAR down-regulates production of the tumorgenic bcl-2, but mAR up-regulates production of bcl-2. The enzyme 5-alpha reductase type II (5AR2) converts testosterone to dihyrotestosterone (DHT). DHT has been shown to bind 5 times more strongly to mAR than testosterone, thereby having the net effect of being tumorgenic, whereas testosterone favors the protective iAR. Note however, that the androgen receptors have multiple functions, some of which are protective and some tumorgenic [Friedman2007, pg 55].

The synthetic progestin Provera™ blocks iAR and thereby disrupts the protective effect of testosterone binding at that site [Birrell2007]; Other researchers have also noted that Provera™ disrupts estrogen receptors as well. Dr. Weyrich notes that, based on Le Chatlier's Law of Mass Action, supplementing with extra testosterone when Proverea is administered can competitively overcome the blockage at iAR by Provera™.

Vitamin D

Vitamin D also has an important role in modulating apoptosis. The active form of vitamin D is 1,25-dihydroxyvitamin D3 (calcitriol), which is formed in the kidneys. Calcitriol binds to the vitamin D receptor (VDR) and increases cell death in both breast cancer [Narvaez2001] and prostate cancer [Guzey2002]. Low Vitamin D status therefore is expected to increase the risk of both breast and prostate cancer.

Diagnosis of Breast and Prostate Cancer

  • Check for BRCA-1 and/or BRCA-2 genetic mutations.
  • Evaluate both ER-A and ER-B activity in biopsied dysplastic tissue. [Ferno1990] has shown that about 70% of breast cancer cases are estrogen-receptor positive; however simply knowing that a cancer is ER+ is not sufficient, since ER-A is carcinogenic and ER-B is protective.

Treatment of Breast and Prostate Cancer

Please see conventional, complimentary and alternative medical treatments for important background information regarding the different types of medical treatments discussed below.

Conventional Treatments

Conventional treatments have been characterized by critics as consisting of "slash, burn, and poison" - that is surgical removal of cancerous tissue, radiation treatment to destroy cancerous tissue in situ, and using selective toxicity to kill cancerous cells (which typically have a different metabolism than healthy cells and thus are more sensitive to chemotherapeutic agents).

Some slow-growing cancers are not treated at all by conventional medicine. For example prostate cancer is often dealt with by "watchful waiting."

Surgical excision of breast or prostate tumors is controversial, since there is evidence that removing the primary tumor increases angiogenesis at metastasized sites [Coffey2003]. Therefore, conservative treatment with hormones, aromatase inhibitors, 5-alpha reductase inhibitors, etc, combined with watchful waiting may be the best approach.

Naturopathic, Complimentary and Alternative Treatments

Low Dose Naltrexone (LDN)

[LDN_Cancer] reports that the late Dr. Bernard Bihari treated approximately 450 patients with some form of cancer, with a 60% success rate, almost all of who had failed to respond to standard treatments.

In particular, 4 patients with breast cancer metastatic to bone and 5 patients with prostate cancer appeared to be in remission. However, prostate cancer patients who have already been treated with chemical castration have not responded to LDN. In one case of prostate cancer, after 4 months on LDN the patient's PSA dropped from 6.3 to 3.4, and after 6 months ultrasound showed a 65% reduction of the tumor. His PSA remained stable for the following 16 months. In one case of breast cancer metastasis to the hip, the patient was considering outpatient hospice when she started taking LDN. Four months later the hip pain had resolved to the point that she could play tennis again, and a year later, a bone scan showed a 40% reduction in the metastatic tumor mass.

Dr. Weyrich has been trained in the use of Low Dose Naltrexone (LDN). However, Dr. Weyrich has not treated any cases of breast or prostate cancer with LDN.

Please see What is Low Dose Naltrexone? for more information.

Hormonal Treatments

[Friedman2013] presents compelling evidence that in most cases, prostate cancer [and breast cancer] is best treated by a combination of increasing testosterone levels to young adult levels, administering aromatase inhibitors to maintain estradiol levels at low-normal levels in order to minimize stimulation of ER-A (which is necessary for cancer promotion), administering estriol (which preferentially binds to ER-B) to stimulate ER-B (which opposes ER-A and thus is protective against cancer initiation).

Tamoxifen, an ER-A antagonist, is also useful in treating breast cancer [ORWJr: and possibly prostate cancer?] [Friedman2007].

The BRCA-1/BRCA-2 mutation damages the protective PR-B, allowing the tumorgenic PR-A unbridled activity. Mifepristone (RU-486) (FDA-approved as a "morning-after" abortifacient) is antagonistic to PR-A, and has been shown to reduce levels of the tumor-promoting protein bcl-2. Unfortunately, use of mifepristone to treat or prevent breast or prostate cancer in BRCA-1/BRCA-2 mutation-positive individuals appears to be a forbidden off-label use in the USA [Friedman2007], [Poole2006].

Since the enzyme 5-alpha reductase type II (5AR2) converts testosterone to DHT, which favors tumorgenesis, high levels of testosterone can be protective if conversion to DHT is prevented through the use of 5-alpha reductase inhibitors such as Finasteride [Friedman2007, pg 55].

Prevention of Breast and Prostate Cancer

[Friedman2013] presents compelling evidence regarding the cause of prostate and breast cancer, and a clear model for both preventing and treating both these cancers, which are primarily driven by hormonal imbalances, especially excess estradiol (see Etiology). In particular, note that estrone (present in horse-urine-derived pharmaceuticals such as Premarin and PremPro, and produced by fat cells in the body) binds ER-A more strongly than ER-B, and hence is pro-carcinogenic, while estriol, which binds more strongly to ER-B, and which is produced mainly during pregnancy, is protective. Thus, pregnancy protects against breast cancer, while common oral contraceptives made from pregnant mare urine (e.g. Premarin and PremPro) promote breast cancer.

In addition to the importance of controlling the type and level of estrogens, testosterone has been found to be highly protective from abnormal estrogen levels [Dimitrakakis2003], [Dimitrakakis2004], [Dimitrakakis2009], [Dimitrakakis2010]. The combination of testosterone and anastrozole (an aromatase inhibitor that prevents conversion of testosterone to estradiol) has been shown to be useful in treating breast cancer survivors [Glasser2010].

Testosterone has also been shown to reduce expression of the pro-cancer ER-A gene, and increase expression of the protective ER-B gene [Dimitrakakis2003].

Testosterone has also been shown to mitigate the endocrine-disruptive effects of Provera™ [Dimitrakakis2004]. However, [Davison2005] has shown that female "serum androgen levels decline steeply in the early reproductive years and [are not affected by onset of] menopause and that the postmenopausal ovary appears to be an ongoing site of testosterone production." Oophorectomy (surgical removal of ovaries) further lowers androgen levels. This implies that as a woman ages, or undergoes oophorectomy, the lower remaining levels of testosterone provide less protection against the endocrine disruption of synthetic progestins such as Provera™ [Friedman2013, pg 76].

It is interesting to note that frequent ejaculation (twenty-one or more per month) have a 33% reduced lifetime risk of prostate cancer [Leitzmann2004].

Maintaining a strong immune system and avoiding excessive exposure to carcinogenic substances are the best defenses against cancer. Ways to maintain a strong immune system include:

  • Maintain adequate Vitamin D levels by cautious exposure to sunlight and supplements as needed. It is important to directly measure calcitriol and supplement calcitriol levels in patients with renal disease, since the kidneys may be unable to convert dietary cholecalciferol (Vitamin D-3) into calcitriol (the bio-active form).
  • Treat functional immune deficiency associated with hypothyroidism [Starr2005, pg 109].

Breast Cancer

Research has shown that starting estrogen replacement therapy (ERT) in peri-menopausal or early-menopausal women reduces the risk of invasive breast cancer. However, if start of ERT is delayed more than 6 years after menopause, this protection is lost. Furthermore, synthetic progestins (but not bio-identical progesterone) increase the risk. Please see the video of Dr. Quigley discussing the truth about the Women's Health Initiative study [Quigley2006].

References for Breast and Prostate Cancer