Integrative Approach to Breast CFCs (Cancer)

In the previous article, we explored how the modern conventional approach to breast CFCs (chronically fermenting cells or cancer), especially the reliance on estrogen-blocking strategies, was based on the observation that most breast CFCs are hormone receptor–positive (HR+), driven in part by estrogen signaling. Despite their well-documented side effects and the persistent challenge of treatment resistance, these hormone or endocrine therapies have remained not only central but often the only treatment offered in conventional care for breast CFCs.

Yet this approach concentrates its efforts on but a narrow aspect of a far more intricate physiology. Breast CFCs are not simply a problem of estrogen and its receptors, rather they arise as an adaptive process just as do CFCs arising from any tissue where the microenvironment is toxic, hypoxic (low oxygen), chronically inflamed, and metabolically imbalanced resulting in mitochondrial loss and/or dysfunction, thus necessitating a fermentative adaptive strategy for survival. The singularity of the “hormone approach”, in conventional oncology ignores these other factors and variables, that are not only involved in the initiation of CFCs, but also their growth, progression, and metastases.  

Moreover, these hormone-blocking therapies not only leave critical aspects of breast CFCs untouched, but they also erode the body’s natural estrogen-dependent resilience by weakening bones, impairing metabolism, disrupting cardiovascular and neurological function, and elevating systemic inflammation. As a result, while the body’s defenses weaken, tumors themselves adapt, shifting hormone receptor patterns from + to – and vice versa as required, generating their own estrogen, and reshaping their microenvironment to survive despite therapy.

Understanding these limitations is essential as it encourages more comprehensive, biologically aligned strategy. Integrative oncology recognizes estrogen’s nuanced role, and instead of blocking or depleting it, focuses on restoring hormonal balance. This approach also supports the foundational systems that underly behavior of CFCs, mitochondrial and metabolic function, immune system, stress physiology, and detoxification pathways. By strengthening the body’s internal environment and working with its natural regulatory systems, integrative oncology aims to create conditions less favorable for CFCs and more supportive of overall health. In doing so, it offers an evidence-based path toward improving treatment response, enhance vitality, and long-term outcomes. Because of the breadth of this topic, however, this article will focus specifically on addressing breast CFCs from a hormonal perspective.

Battle vs Balance  

The concept that naturally occurring biochemicals produced by the body for healthy functioning can be categorized as “good” or “bad” is necessary in order to justify the “military approach” of conventional medicine. First the enemy is identified, via a process known as “diagnosis”, and then the appropriate “weapons” in the form of 1) surgical removal, different ablative techniques (radio frequency waves, microwaves, cryo-, i.e., freezing, laser interstitial thermal, high intensity focused ultrasound, and others) 2) poisonous chemicals (chemotherapy, targeted therapies, check point inhibitors, etc.) 3) external beam radiation in the form of ionizing radiation, proton radiation, or internal radiation therapy, e.g., brachytherapy, radioactive drugs can be assembled as per protocol to “destroy the enemy”. 

Moralizing biology by using words such as “good” or “bad” has no place in science, for in truth, all of the products of biology are necessary for optimal functioning (health) and it is only when there is an imbalance through excess or deficiency and toxic overload that dysfunction occurs along with multiple adaptive responses that maintain function temporarily but ultimately fail due to the deficiencies and/ or excesses of essential substances required by the body to function. 

Clearly, then the blocking of the production of estrogen with GnRH agonists, e.g., leuprolide that puts women into chemical menopause, or using estrogen receptor blockers, e.g., tamoxifen, enzyme inhibitors, e.g., anastrozole, estrogen receptor down regulators, e.g., fulvestrant serve to increase the already significant imbalances that contributed to the CFC initiation, growth and progression, rather than to restore the balance necessary for health. 

The Women’s Health Initiative was a large, randomized clinical trial across 40 U.S. centers from 1993 to 2004 studying post-menopausal hormone replacement therapy (HRT).  The study design included two arms: 

1. Estrogen + Progestin (women with a uterus) 16,608 women, which was stopped early in July 2002 due to preliminary findings of an increased incidence of breast CFC, heart “disease”, stroke and blood clots.
2. Estrogen-Only (Women without a uterus) 10,739 women, which was stopped early in February 2004 due to increased incidence of stroke, increase in blood clots, no cardiovascular benefit and later analysis showed a slight decrease in breast CFC.
   
   

Initially, all hormone replacement therapy (HRT) was stigmatized however, after the revised analyses 2005-2017 showed that starting HRT earlier was protective and ultimately that the synthetic progestin (MPA) was the cause of many of the negative effects. 

All of the hormones tested were synthetic, patented pharmaceutical products, not biologically identical hormones, therefore the results are not applicable to bioidentical hormone therapy (BHT):

No part of the WHI studied:

1. estradiol (E2)
2. estriol (E3)
3. micronized bioidentical progesterone (P4)
4. transdermal bioidentical hormone delivery
5. customized compounded hormone formulations
   
   

Completely different molecules:

WHI tested:

1. Conjugated equine estrogens (CEE) are derived from the urine of mares, not humans
2. Medroxyprogesterone acetate (MPA) is a synthetic progestin, not human progesterone.
   
   

Bioidentical hormone therapy uses:

1. Estradiol and estriol that are identical to human ovarian estrogens.
2. Progesterone (P4), which is identical to human ovarian progesterone.
   
   

None of the data, including safety data can be generalized from one molecule to a different molecule because there are different receptors, metabolites, gene expression patterns, risks, and outcomes.  

Synthetic progestin (MPA) behaves opposite to real human progesterone:

MPA

1. Increases breast cell proliferation
2. Increases blood clotting
3. Increases inflammation
4. Reduces beneficial effects of estrogen
   
   

Bioidentical progesterone (P4)

1. Reduces breast cell proliferation
2. Does not increase clotting
3. Is anti-inflammatory
4. Enhances estrogen’s cardiovascular benefits.
   
   

WHI used oral synthetic estrogen, not transdermal estradiol and estriol

Oral estrogens (like CEE):

1. Undergo first-pass liver metabolism
2. Increase clotting factors
3. Increase C-reactive protein
4. Increase blood clot risk
   
   

Transdermal estradiol and estriol

1. Does not increase clotting
2. Does not activate liver coagulation pathways
3. Has a far safer risk profile
   
   

The routes of administration alone make the WHI findings non-transferable.

Biologically identical hormones, being chemically identical to human hormones were not included because they cannot be patented, precluding large profits for pharmaceutical companies. Furthermore, compounding pharmacies do not participate with the large corporate R&D structures that fund clinical trials. Therefore, despite decades of clinical use, without economic incentives, there have not been, and neither will there ever be any randomized controlled trials to evaluate bioidentical hormones. 

Restoring Balance with Bioidentical Hormones

As discussed in the previous article in this series, there are two basic estrogen receptors ERα and ERβ and each can be triggered differently by the three basic estrogens, estrone (E1), estradiol (E2), and estriol (E3). To complicate these interactions between the types of estrogens and their receptors is the fact that there are at least four isoforms of ERα and for ERβ there are at least five isoforms. The term “ER+ breast CFC” refers to tumors that express ERα, hence the primary clinical target for endocrine therapies such as tamoxifen and aromatase inhibitors. While ERβ is usually co-expressed in ERα-positive tumors, its presence does not define the ER+ status; rather, it serves to modulate the tumor’s response. 

Therefore, although ERβ activation can shrink tumors in experimental models, the clinical utility of targeting ERβ remains under investigation, particularly due to the need for highly selective agonists that avoid cross-activation of ERα.

ERα promotes tumor growth and progression in hormone-responsive CFCs like breast, ovarian, endometrial, prostate, and actually many other locations. ERβ, on the other hand, acts as a tumor suppressor, especially when co-expressed with ERα. So, clearly an important strategy is to increase ERβ activation with the appropriate ligands (hormones-any substance that can activate the receptor) and to keep in mind that none of them are pure agonists for one or the other (ERα or ERβ) but rather have differing affinities for both. For example, estrone and estradiol have strong affinities for ERα with much less affinity for ERβ, hence the net effect is ERα. The opposite occurs with estriol, which has a net ERβ effect, yet with a minor ERα effect. This is actually the most efficacious, since the net is ERβ with consequent tumor suppression, but since it is a mild agonist for the ERα it means that it is already occupying the receptor site thereby preventing (blocking) estrone and estradiol from activating it, much like what tamoxifen is supposed to do. Important to note is that the phytoestrogens in soy and flaxseed have the same beneficial effect as estriol.

Eliminating Estrogens or Blocking their Effects is NOT Healthy

Recent studies demonstrate that replacing estrogen in women with deficiency reduces the risk of breast CFCs. This stems from the complex relationship between breast CFC biology and estrogen where estrogen can both stimulate tumor growth (via ERα) and, in estrogen-deprived states, induce CFC cell death. Furthermore, estrogen supports bodily functions such as muscle maintenance, glucose regulation, mitochondrial energy production, mental health, normal lung development and function, bone health, cardiovascular health, digestive and bowel health and immune defences, all of which reduce the biological conditions favouring breast CFC development and progression.

Studies on postmenopausal women show that estrogen replacement can prevent the typical age-related decline in immune cells, including T cells, B-cells and monocytes (macrophages and dendritic cells).

Food Choices That Support Healthy Estrogen Levels

Diet affects estrogen metabolism at multiple levels, from liver detoxification and intestinal elimination to estrogen signalling in breast tissue, making it a powerful tool for restoring optimal hormonal terrain.

1. Diet Affects the Liver Enzymes That Process Estrogen
   
   

An important contributor to estrogen levels is the liver’s capacity to process and eliminate estrogen. The liver’s estrogen metabolism is highly coordinated through Phase I and Phase II detoxification enzyme pathways in the liver. Phase I enzymes (such as CYP1A1, CYP1B1) determine whether estrogen is converted into harmless or carcinogenic metabolites while Phase II enzymes such as Estrogen Sulfotransferases (SULT1E1), are responsible for safely deactivating and eliminating these metabolites from circulation. 

Some estrogen metabolites (such as 16α-hydroxyestrone and 4-hydroxyestrone) produced by Phase I enzymes cause cellular damage and tumor progression while others (especially 2-hydroxyestrone) are neutral or even protective. Therefore 2:16 ratio is considered as a biomarker of breast CFC risk and assessment of status when breast CFC are present. Factors such as environmental toxins and chronic stress can shift metabolism toward more carcinogenic pathways (16α-hydroxyestrone and 4-hydroxyestrone)

Let Thy Food Be Thy Medicine and Thy Medicine Be Thy Food

• Cruciferous vegetables (broccoli, kale, cabbage, bok choy, Brussels sprouts) contain glucosinolates, which are sulphur-containing compounds that give them a pungent or bitter taste and aroma. These compounds are broken down into isothiocyanates and indoles, when the plant is chewed or cut. Hence, these breakdown products, such as indole-3-carbinol (I3C) and diindolylmethane (DIM), induce Phase I CYP1A1 and CYP1A2 enzymes while balancing CYP1B1 activity, increasing the protective 2:16 ratio. There are many other effects such as protecting DNA from damage. Measurable change was found in women adding 500 g/day of broccoli to a diet.
  
  

Broccoli is a good source of glucoraphanin, which converts to sulforaphane, while cabbage contains glucobrassicin, which converts to indole-3-carbinol.

It is imperative to keep in mind that the enzyme myrosinase is inactivated when heated above 47 °C (119 °F), so that these important bioactive molecules like I3C, DIM and others will not be produced. In other words, cooking prevents one from obtaining the health benefits from these vegetables. 

• In a study of 3,080 women with breast CFCs, those who consumed the most vegetables especially cruciferous had up to a 52% reduction in recurrence risk.
• Flaxseeds, rich in phytoestrogens called lignans, have been shown to favorably shift estrogen metabolism by increasing the 2:16 hydroxyestrone ratio. Clinical studies demonstrate significant changes in women consuming 10–25 g of ground flaxseed per day (approximately 1–2 tablespoons).
• In a study of women with breast CFCs, consuming 25 g of flaxseed per day altered CFC behavior toward a less aggressive pattern by slowing cell growth, increasing cell death (apoptosis), and reducing HER2 levels.
• Other liver-supportive phytonutrients include polyphenols from berries, rosemary, green tea, and citrus fruits which modulate CYP enzymes enhancing safe estrogen elimination
• Flavonoids such as naringenin found mostly in citrus fruits, especially in the peel, activates estrogen sulfotransferase (SULT1E1), Phase II enzyme, enhancing the conversion of active estrogens into their inactive sulfate forms
• High-fiber diet is linked to increased levels of sex hormone–binding globulin (SHBG), which reduces the amount of biologically active estrogen in circulation.

2. Diet Influences Estrogen-Metabolizing Microbes
   
   

In addition to liver, the gastrointestinal tract plays a central role in regulating estrogen levels. Estrogens circulate from the liver into the intestine, where they can either be excreted or reactivated and sent back into the bloodstream. The key determinant of this process is the gut microbiome, especially bacteria that produce an enzyme called β-glucuronidase, which frees estrogen from its conjugated form and allows it to be reabsorbed. 

Studies comparing dietary patterns have found that typical Western diet high in processed foods and meat and low in fiber tend to favor bacterial groups such as Clostridia and Ruminococcaceae, which are major producers of β-glucuronidase and promote estrogen reabsorption. In contrast, diets rich in fiber, and other plant compounds correlate with lower enzyme activity and higher fecal estrogen excretion. 

Postmenopausal women with breast CFCs often show distinct microbial profiles enriched in β-glucuronidase-active bacteria, showing that the microbiome can directly contribute to excess estrogen exposure. Some species can even reactivate estrogen locally within breast tissue.

3. Plant Compounds Modulate Hormone Activity in Breast Tissue
   
   

Many plant compounds can influence hormone signalling in breast CFCs. Hormone receptor profiles in breast CFCs are not fixed. Instead, tumors can shift their estrogen and progesterone receptor status as they progress, depending on the signals from the tumor microenvironment. As receptors are gained, lost, or modified, the tumor’s sensitivity to hormone therapies can change dramatically, contributing to treatment resistance. As discussed previously, the balance between estrogen receptor subtypes matters: activation of ERα promotes tumor growth, while ERβ suppress it. The behaviour of CFCs can therefore depend on its ERα:ERβ ratio, meaning that the same hormone, estrogen, can either fuel or suppress growth depending on the receptor context.

Phytoestrogens are compounds naturally found in many plants, fruits, vegetables, legumes, and seeds that can weakly mimic or modulate estrogen activity in humans. They possess a phenolic ring, enabling binding to estrogen receptors ERα and ERβ (with higher affinity for ERβ). Have very weak estrogenic activity—about 10²–10⁵ times weaker than human estrogens. 

Main Classes of Phytoestrogens

1. Isoflavones (most potent): genistein, daidzein (found in soy, chickpeas, lentils, beans)
2. Lignans: enterolactone, enterodiol (found in flaxseed (highest levels), whole grains, legumes, fruits, vegetables)
3. Coumestans (found in sprouting plants e.g., clover sprouts).
   
   

Mostly studied phytoestrogens such as genistein (from soybean), sesamol (sesame seeds) and quercetin (from onions, apples, berries etc.) have shown the remarkable ability to restore lost hormone receptors in breast CFCs by epigenetically reactivating ERα in previously ERα-negative cells. In animal studies, genistein not only slowed tumor growth but also re-sensitizes these tumors to anti-estrogen drugs such as tamoxifen, converting endocrine-resistant CFCs back into treatable ones. 

Besides phytoestrogens, compounds such as curcumin from turmeric has been shown to downregulate ER activity and selectively kill breast CFCs.

Because some effects of plant compounds occur at concentrations much higher than what diet alone can provide, certain compounds (such as quercetin and curcumin) can be administered intravenously to achieve the necessary levels in the body. In a clinical study, women with breast CFCs who received intravenous curcumin alongside chemotherapy had better tumor responses and experienced less fatigue than those who received chemotherapy alone.

Epidemiological studies show that populations (such as Japanese) with high (20–150 mg/day) phytoestrogen intake of soy isoflavones show lower incidence of breast CFC rates than Western countries (phytoestrogen intake 1–3 mg/day). When Japanese populations migrate to the West, their breast CFC incidence rises within 1–2 generations, suggesting environmental and dietary rather than genetic causes.

Oral Health  

Interestingly, research has found that some bacteria typically found in the mouth, including Fusobacterium and Streptococcus, also appear in breast tissue.

One oral bacterium, Fusobacterium nucleatum, has drawn special attention. Common in people with gum disease, it has been detected in breast tumors and appears to help CFCs grow by weakening immune responses. 

In addition to affecting the gums, persistent root-canal infections often harbor bacteria such as Fusobacterium nucleatum even after standard treatment. Their continued presence shows that some microbes are highly resistant to conventional cleaning procedures. Because of this, practitioners in biological dentistry use additional tools, such as ozone or laser-based disinfection, to eliminate resistant infections. 

Eliminating Environmental Toxins

Research shows that environmental toxins play a much bigger role in breast CFCs than previously recognized and are strongly linked with CFC progression, treatment resistance, and poorer outcomes. The list of harmful compounds is vast but some of the most prevalent ones are:

• Heavy metals (cadmium, arsenic, nickel, lead etc.) which are often found in breast CFC tissue in elevated concentrations.
• Environmental hormone disruptors or xenoestrogens, a broad range of chemicals found in pesticides, personal care products, plastics and industrial chemicals that can mimic or interfere with natural estrogen signaling.
  
  

By accumulating in the body these chemicals, in addition to directly causing cellular damage and CFCs, can disturb hormonal balance even at low doses by:

• Disrupting the liver’s ability to detoxify and eliminate estrogens (and xenoestrogens) by inhibiting a key enzyme estrogen sulfotransferase, leading to higher levels of active estrogen.
• Increasing estrogen production by stimulating aromatase, the enzyme that converts androgens into estrogen.
• Shifting estrogen receptor balance in breast tissue: Increase ERα (growth promoting) and decrease ERβ (growth suppressing).
• Reducing ER and PR expression leading to more aggressive, hormone-insensitive and therapy resistant tumors.
  
  

How Well Can the Body Get Rid of Toxins?

An important study found that regular, everyday exposure to parabens and phthalates, common ingredients in many personal care products, caused measurable biological changes linked to CFCs in non-cancerous breast cells. 

However, these changes were reversable. When participants switched to xenoestrogen-free personal care products for 28 days their urinary levels of parabens and phthalates dropped and breast-cell signaling normalized.

This finding suggests that limiting exposure by choosing safer personal care products can meaningfully reduce toxic load.

However, CFCs have impaired systems for transporting substances in and out of the cell, causing chemicals circulating in the blood to accumulate inside tumors.

As breast tumor progresses, its ability to properly regulate and eliminate toxins becomes increasingly disrupted due to stagnant blood and lymph flow. Therefore, supportive practices such as Lymphatic Drainage Therapy can help toxic fluid removal from the tumor while Sauna may further aid detoxification, as some of these compounds are excreted more efficiently through sweat than through urine.

Healing the Tumor Microenvironment  

Tumors grow in abnormal low-oxygen (hypoxic) environment that differs from the healthy tissues around it. A big reason for this is the tumor’s own blood vessels. Unlike the efficient network in healthy tissues, tumor blood and lymph vessels are chaotic, leaky and disorganized, unable to circulate blood and remove fluid properly. 

As a result, several problems occur:

• Fluid and pressure build up inside tumors which makes the delivery of therapeutic agents more difficult.
• Immune cells struggle reaching the tumor.
• Waste products, toxic chemicals and inflammatory signals accumulate.
• The tumor microenvironment becomes increasingly hypoxic (oxygen deprived). Hypoxia activates hypoxia-inducible factor -1α (HIF-1α), a key regulator of survival under low-oxygen stress. HIF-1α rewires CFC metabolism and pushes tumors toward more aggressive behavior. Hypoxia and HIF-1α are strongly linked to loss of hormone receptors (leading to harder-to-treat triple-negative tumors), resistance to therapy, weak immune responses, greater risk of metastasis, and worse outcomes overall.
  
  

Research shows that weak blood circulation in tumors may be worsened by estrogen-deprivation therapies. Even in estrogen-receptor–negative tumors, estrogen receptors are present in the surrounding stromal and endothelial cells. Estrogen acts on these supportive cells, and at optimal levels it helps maintain more organized and functional blood vessels, conditions that improve blood flow to the tumor. When estrogen is removed or blocked, this vascular stability can deteriorate, potentially intensifying hypoxia and the challenges it creates.

The tumor microenvironment, its blood vessels and oxygen levels and can be reshaped by targeted therapies and lifestyle.

Strategies to improve tumor oxygenation:

1. Increase oxygen availability and suppress HIF-1α

• Exercise With Oxygen Therapy, Hyperbaric Oxygen Therapy
• Correction of anemia (iron, erythropoietin)
• Ozone Therapy or EBOO (Extra-Corporeal Blood Ozonation and Oxygenation)
• High-Dose Intravenous Vitamin C (suppress HIF-1α)
  
  

2. Improve blood flow

• Hyperthermia
• Lymphatic Drainage Therapy
• Physical Movement
• PEMF (Pulsed Electro-Magnetic Field) Therapy
• Acupuncture (especially peritumoral electroacupuncture)
  
  

By restoring healthy blood flow and oxygen levels in tumor tissues, these therapies help shift the tumor toward a less aggressive state and improve the effectiveness of all treatment approaches.

In conclusion, integrative oncology, unlike conventional estrogen-blocking strategies, addresses the hormonal aspect of breast CFCs by restoring the body’s natural physiological balance, one that sustains the health of every organ system and the body’s innate capacity to heal. This means not only correcting hormone levels with bioidentical options when appropriate but also strengthening the detoxification pathways of hormones and environmental toxins, repairing and stabilizing the gut and oral microbiome, and using phytochemicals to modulate hormone signaling. Equally important is transforming the tumor microenvironment into one that is more oxygenated, less inflamed, and less favorable for CFC progression.

By expanding the focus beyond estrogen blockade and supporting the entire biological terrain, we can enhance treatment effectiveness, reduce side effects, improve quality of life, and build a more sustainable foundation for long-term health.

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