Managing Hormone Therapy in Breast Cancer

Whether you’re interested in bio hacking or rehab tools the principle is the same; you want to explore how one can use their own body’s capacity to make things better. In a time of suffering and symptom burden, often the last thing that people with breast cancer want is more medication. On the flip side, it can be just as difficult to ignore the remaining symptoms and come to terms with the limiting ‘new normal’. If you don’t want to hear the usual jargon like fan your face to control hot flashes, take Tylenol, or stay hydrated but instead are looking for some new evidence informed tools that work, read on.





Post-Treatment? Now What?! Long Haul Cancer Syndrome?


I saw a satirical GIF the other day from 'the cancer patient' on instagram representing ‘how a cancer patients feels post treatment’ and it showed her being thrown off a bridge as the oncology team said, “you’re discharged and prepare for return to work”. One should just be grateful that they’ve survived, right?! Sometimes after an exhaustive treatment period there is little focus left for all that remains. Coupled with pressure from medical insurance providers to return to work, it all can be a lot to bear. Symptoms during treatment are plentiful but just can be just as burdening post-treatment, I like the analogy of 'long haul cancer syndrome', akin to long haul covid. Symptoms related to long haul cancer are under discussed, under-funded and often poorly treated. The symptoms that remain can pose an immense burden on quality of life. Let’s take a deep dive into some accessible and evidence rich ways to build yourself up a bit.


Patients often share that after general cancer treatment they hope to learn tools to feel a bit more like themselves again, aiming to return to activity and work. Often they are burdened with 'long haul cancer syndrome' presenting as a variety of symptom burden. This can include persistent fatigue, stiffness, pain, neuropathies or more specific set backs such as chording or fibrosis. Although medication can have a very important role in cancer treatment, in terms of symptom management post- treatment it has less efficacy. There are many tools that can be incorporated into a rehab plan to help better manage the side effects of cancer treatment and in this case hormone therapy. Rehab plans involve working with the body’s capacity and teaching it new pathways. Cancer physiotherapy involves a clinically personalized rehab plan specific to you to achieve so.





Take pain for example, literature shows that opioid use in the long run often leads to hyperalgesia or ‘hypersensitivity’ and therefor is ineffective for persistent pain. We have also come to understand that pain is protection, not detection and certain medications such as hormone therapy and chemotherapies can sensitize our systems, reducing the threshold for pain. Think of cancer treatment as reigniting the reactive whinny child within all of us, it makes the system more sensitive, more likely to react and protect.


Pain is best treated with a multimodal approach, not just a prescription, often incorporating cognitive behaviour therapy and especially movement prescription. We actually have the capacity to produce endogenous opioids, which means our body can actually produce pain killing chemicals; so in the case of pain, dopamine, opioids and sensitization the picture is much bigger than just ‘killing pain with medication’. I’ve treated more lower back pain that I can begin to tally and seldom is a patient finding any consistent relief in the long term with just pill popping. Relief comes from a comprehensive approach: education on pain, capacity building in the body and managing big picture lifestyle stuff life sleep and stress.



Types of Hormone Therapy Used in Breast Cancer:

Aromatase Inhibitors (AI’s)

Function: block estrogen receptors or production and reduce estrogen conversion

Population prescribed: often post-menopausal and estrogen positive cancers

Examples: Anastrozole/Arimedex, Exemestane, Letrozole/Femara, Vorozole, and Testolactone

Common side effects: AIMS, arthragia/myalgia, hot flashes and nausea


Steroidal Hormone Receptor Blocker, Estrogen Receptor Down Regulator (ERD) and Selective Estrogen Receptor Modulator (SERMS), Cycling-Dependent Kinase (CDK)

Function: blocks estrogen receptors, binds to estrogen and reduces ovarian estrogen

Population prescribed: pre-menopausal and estrogen +ve cancer

Examples: Tamoxifen/Nolvadex, Faslodex, Nolvadex and Soltamox and Ibrance/Palbociclib

Common side effects: hot flashes, joint pain, sleep disturbances and nausea


Estrogen suppressing supplements (occasionally prescribed)

Calcium D-glucarate

Diindolylmethane (DIM) founds in cruciferous vegetables (broccoli, kale etc.)



Common Symptoms from Hormone Therapies Used in Breast Cancer:

Poor Tolerance of Exercise, Ouf!



If your treatment includes hormone therapy, in addition to side effects from chemo and radiation, often your hormones will also undergo changes. Fortunately, hormone therapies have efficacy increasing survivorship rates up to 50%, but it doesn’t mean they are easy! The pathway of cancer treatment often leads to immense de-conditioning and at times cachexia (muscle wasting). Together, this makes exercise and the recovery from it a challenge. We know estrogen plays an important role in promoting glucose use by particular muscle fibres therefor impacting stamina. Hormone treatment impacts estrogen levels. This in turn explains why the menstrual cycle can effect women's stamina and performance; and helps explain why hormone therapies that decrease estrogen availability in the body can also impact tolerance to exercise and the recovery from it. Estrogen has many roles but the ones that concern us here are its role as an anti-inflammatory, metabolic accelerator and bone builder. There for, decreased levels of estrogen have been associated with malaise, fatigue and poor exercise stamina


Hot flashes, Baby!

Most hormone therapies are associated with an increased frequency of hot flashes. Although one might think hot flashes are simply an onset of ‘feeling hot’; anyone who has had one can testify that it is much more than that! A hot flash can involve a sudden onset of profuse sweating, a rapid increase in heart rate and an increase in body temperature; therefor creating a feeling of overwhelm. The typical treatment for menopausal women is systemic estrogen therapy or estrogen-progestogen, hence in breast cancers that are hormone sensitive estrogen treatments aren’t an option.





Joint and Muscle Pain, Ouch!

Within the first 3 months of hormone therapy, patients often report increased stiffness in their hands, knees, back and other areas of their musculoskeletal (MSK) system. We can differentiate this pain from other causes such as osteoporosis or osteoarthritis because it typically presents in both sides of the body and in multiple joints in the first 3 months of hormone therapy. Often it is worse in the morning and worse after long periods of immobility. For some the stiffness is intolerable and often goes misdiagnosed by clinicians outside of oncology. We can classify the increase in joint pain/stiffness and muscle pain/stiffness as arthralgia/myalgia but more so it is often known often as Aromatase Inhibitor Musculoskeletal Syndrome (AIMS). Decreased estrogen impacts joint/tissue inflammation, decreases elastin and collagen production together causing loss of tensile strength in tendons and increasing MSK pain.


Cancer treatment often leads to systemic changes that present as de-conditioning, pain and fatigue; generally changes in dopamine utilization (abnormalities in dopaminergic neurotransmission) also occur. Patients often have less dopamine release compared to pre-diagnosis. Dopamine changes are particularly evident in cases where cancer related depression and cancer related fatigue are present. Decreased activity throughout the treatment period coupled with less dopamine release together frequent increased musculoskeletal pain and joint stiffness. Therefor while undergoing hormone therapy decreased levels of dopamine and estrogen have been associated with higher levels of musculoskeletal pain.


Nausea, Blah!

Often changes in hormones are paired with nausea, hence the first trimester for women expecting is often nausea laden. When I personally started oral hormone therapy as part of an IVF prep, the first 3 months were rampant with nausea likely attributing to changes in estrogen taking place. At times my strength training was very impaired; I was simply too nauseous to work at higher intensities and had frequent muscle soreness. Many women report that certain phases of their menstrual cycle are coupled with nausea; once again highlighting that changing hormones can lead to nausea.





We know that nausea is heavily impacted by dopamine receptors (in the area postrema in the medulla of the brainstem), this chemoreceptor trigger zone contains ‘type D2 receptors’, which poses some questions surrounding the relationship between dopamine and nausea. If cancer treatment can impact dopamine as noted above; perhaps this is also related to how hormone therapy may cause nausea. Therefor, changing estrogen levels and a decrease in dopamine release may be associated with the onset of nausea in hormone therapy treatment.



Managing Symptoms of Hormone Therapy in Breast Cancer


Cool It Down. Brrrr.

Our common response when we are feeling nauseous or having a hot flash is to unbutton our blouse, fan our face or hydrate. Research has confirmed that our most efficient form of heat exchange lay in venous arterial anastomoses in the palms of our hands, soles of our feet and forehead. In other words, these are web like areas rich in blood vessels. The skin there has little hair and a high concentration of direct transition from arteries to veins leading to efficient heat transfer. Otherwise known as glabrous tissues; it is an effective portal into the body’s core temperature. When having a hot flash, or feeling nauseous the soles of your feet, palms of your hands and forehead are portals to quickly change your body’s core temperature and control symptoms.


Say you’re feeling nauseous or a hot flash onsets, try placing your bare feet in 1 inch of cool water or place your bare feet on an icepack layered with a towel. Better yet, lay a cool wet towel on your forehead or grab a natural ice cube in a ziplock bag within the palm of your hand. Note that we are aiming for a ‘cool sensation’ here not a ‘cold sensation’ as we don’t want vasoconstriction to occur. The temperature should be comfortable but evidently cooler. Doing the above will send quick signals to your brain in the most efficient manor possible and lower your core temperature, reduce sweating and therefor allow you to feel more comfortable. Try it and tell me what you think!


Get In the Cold. Yikes!

First let’s differentiate from the above where we are referring to a ‘cool sensation’; noticeably cool but comfortable. In this case, we are talking about a ‘cold sensation’, a temperature that is uncomfortable and makes you want to escape it. The chosen cold temperature however needs to be safe, meaning that one would start slowly, building into colder temperatures over time. We are also talking about deliberate cold submersion in this case, which involves a lot more than just the glabrous tissue mentioned above; in this case we are aiming to be submerged from the neck down. Despite the research solely including submersion from the neck down, in this case we will also include cold showers; although there is little research for this I myself having done deliberate cold exposure for 2.5 years can testify that the shock from a cold shower still stimulates a reaction although potentially not as strong as a full submersion exercise.





The benefits highlighted in the research state the following parameters:


1) Cold submersion needs to be from the neck down

2) 11 minutes/week total

3) A temperature that is uncomfortably cold such that you’d like to escape it.


We can be flexible here, noting that some days you will be more sensitive and some exposure is better than nothing. Hence in my recommendation, a cold bath even if you aren’t fully submerged or a cold shower are still effective, especially if you can’t access a lake, ocean or soaker tub. We don't all have large tubs and ocean front porches so indeed, let's welcome accessibility and support showers.


So why the cold one might ask? What the heck does ‘discomfort’ offer? Well mental resiliency for one, which we will discuss in another blog on mental health and cancer, but more so it offers dopamine, a metabolic boost and effects levels of interleukin-6 a pro-inflammatory cytokine. There was even an interesting study on chemotherapy related peripheral neuropathy pain and the use of ‘frozen gloves’; we’ll discuss some tools for managing chemotherapy induced peripheral neuropathies in our next blog. As for the uncomfortable, numbing and want to run from sensation known as the cold, amazingly it can reduce inflammation and make us feel really good. Deliberate cold submersion can cause a 200-300% increase in endogenous dopamine secretion in the body; this neuro-modulator helps us to feel motivated, focused, alert and quite simply good.





Dopamine is a catecholamine; the brain has many distinct dopamine pathways which play a major role in the motivational component of reward-motivated behaviour. Dopamine is termed a ‘motivational salience’ hormone, which means that it helps to propel behaviour towards a desired outcome resulting in feeling really really good. It also effects insulin and gastrointestinal motility to name a few and has many other cascading impacts such as its impacts on metabolism and immunity. Here, we are focusing on a cold exposure protocol and its ability to impact symptoms of joint pain, nausea and fatigue. We know that nausea, fatigue and pain may be linked to lower levels of dopamine as noted prior. Deliberate cold exposure will increase your levels of dopamine by 200-300% and if done according to the protocol listed above over time, may help manage nausea, pain and fatigue.


We also know that exercise intolerance post cancer treatment can be a result of musculoskeletal complications such as chording, radiation fibrosis syndrome, treatment induced fatigue, lowered estrogen levels and many other factors. The above can make returning to exercise frustrating, painful and lead to push crash cycling. There is strong science that exercise recovery can be improved through the cold exposure protocol, hence athletes of high levels have been using cold submersion after hard training sessions for decades now.


The lactic acid that remains in the system after high intensity training or strength to fatigue can often result in delayed onset muscle soreness “DOMS”. Recovery from cancer is very different than being a high-performance athlete, but recovery and controlling inflammation are still important in both cases. I have made reference before in my video lectures and social posts that battling cancer being similar to being an astronaut. There are added barriers that come from cancer treatment akin to the barriers of being in space. Poor recovery, nausea and fatigue can make light exercise challenging. For those with cancer, light exertion can feel like training for the Olympics.





Returning to exercise for those with cancers looks different for every patient depending on age, cancer type/stage, treatment phase, health history, symptom burden and baseline fitness prior to diagnosis. Exercise as medicine promotes survivorship; we aim to support patients being active all throughout treatment, but prescribe a graded rehab plan and a phase of training with a percentage of heart rate reserve that is individualized to the patient's phase of treatment. A personalized rehab plan prescribed by a cancer physiotherapist is a safe and effective way for patients to exercise through-out treatment or and post, getting back to the things they love.


For most middle-aged women with breast cancer, having undergone surgery, chemo, radiation, reconstruction and hormone therapy, exercise throughout treatment often involves a walking program which we will call zone 1 aerobic activity and strength training using lighter loads with higher repetitions. We aim to promote joint health and bone density after a period of unloading (assuming activity was regressed through-out treatment) through a weight bearing and stabilization approach. Chemotherapy treatment often involves regular echocardiograms to monitor the cardio-toxic effect of some treatment regimes, hence choosing a cancer physio guided rehab plan is an optimal plan. Cancer physiotherapists support a return into a 6/10 intensity (rating of perceived exertion) for both strength and aerobic activities once chemotherapy is complete, increasing the intensity over time as symptoms allow.





Often, despite hormone therapy being ‘the final phase’ of breast cancer treatment, patients find their activity tolerance can regress. Symptoms of poor recovery occur such as fatigue and muscle soreness can hinder progress. Once again, this is where deliberate cold exposure following the protocol above may offer some great benefits with promoting recovery from exercise, a nice drop of dopamine and allow consistency with exercise as opposed to the push/crash cycling we often see. We know that consistency is the mother of all progress in fitness; exercise as medicine is all about a safe graded and consistent approach to exercise personalized to your symptoms. Consistent exercise as medicine is the most effective tool for managing joint and muscle pain in the long term. In addition, through the use of cool temperatures on glabrous tissue to manage hot flashes and a cold exposure protocol to better manage nausea, pain, fatigue and exercise recovery; my hope is these simple tools in addition to a personalized cancer rehab plan will help increase your stamina and help you feel just a bit more like yourself again.




A Note from The Blogger:

With an aims to curate the latest science, and provide evidence rich tools, I think it is important to understand that not all questions can be answered and good science seeks to provide more and more questioning over time. I urge you to shy away from sweeping statements and soap box leaders with strong claims. Often new science is just around the corner. All of my patients have been told a lot of ‘no and don’t’ statement through-out their journey; at times mitigating risk is important but one must always ask at what cost.


I have worked with many patients with breast cancer that were told to never do a push-up, never plank again, or those with lymphedema that were told to never exercise at higher intensities, or never exercise without a compression sleeve. Every phase of treatment, every intervention and there for every new tool used is a very personal decision. Informed decision making and a graded approach with room to observe can lessen risk and open up a lot of possibility. My ask is simple, I ask that you ask good questions too, as much as possible and keep them coming. Understand that not all of them will have answers, but in the unknown try to remain curious, hopeful and even optimistic. If your sense of self and psychology benefit immensely from exploring your capacity as a human being, then I challenge you to explore the boundaries a bit; you might just be little surprised.






*Disclaimer: If you have not been assessed by a cancer rehabilitation clinician, or have thermoregulatory dysfunction, severe lymphedema or are actively undergoing a chemotherapy regime such oxaliplatin which can cause cold sensitization, please consider speaking with your medical oncologist and/or cancer rehab physiotherapist/occupational therapist before starting any new health regime.