It’s funny how people think the symptom is the problem and not the reflection of the problem.
If you smack your head and get a headache, the cause is the hit on the head, and the resulting symptom is the headache. It’s easy to connect the dots.
But most people see the problem as the headache, not the symptom, when the cause is not apparent.
Functional medicine is all about identifying the problems that are causing symptoms.
It sometimes gets a bad rap because it is judged by the solutions often offered by functional medicine practitioners, which can sometimes be debated.
However, the solutions try to fix what has been identified as the underlying problem, although this is not simple.
If an area of the body is not performing as it should, can it create the symptoms the person is experiencing?
Yes. After all, what else would it be? Unless there’s an external factor like smacking your head on a wall.
This is what is so frustrating about what happens to most people after they finish their cancer treatment. It’s where understanding a functional approach comes in handy.
There are so many questions, and no explanation is given to the person as to what happened to their body.
If you have had cancer, you know there are symptoms you’ve been dealing with before treatment. And now you have a bunch of new ones because of the treatment. It’s impossible not to wonder if you should be afraid of these symptoms.
Let’s face it. Cancer is all about fear. Before, during, and after.
This is why understanding how the body functions is helpful. It certainly helped me. I had a good understanding of what had gone wrong in my body that led to the cancer evolving. I knew the effects of all cancer treatment could have, in my case, surgery. And I know what areas of the body, like the gut, the vagus nerve, and the liver, take a beating during treatment.
So, what kind of information exists about after cancer treatment?
Chronic pain can persist for years after treatment, often linked to surgical nerve injury, scar tissue, or musculoskeletal damage, and in some survivors, it never fully resolves.
Cognitive impairment (“chemo brain”) may gradually improve, but a subset of patients report deficits in memory and executive function that last a decade or more.
Chemotherapy-induced peripheral neuropathy frequently improves within months, yet in many cases, neuropathic pain, numbness, or tingling in the extremities becomes a long-term consequence of the treatment.
Radiation toxicity can produce delayed effects such as enteropathy or plexopathy that emerge months to years post-therapy, and once established, these conditions are often chronic.
When you look at after-cancer treatment in this way, how can you not think of what areas of the body no longer function as they need to? And if this has been studied, then why are there no programs or protocols to help people after cancer treatment?
Why are cancer recoverers (don’t care if it’s not a word) left to flounder?
One key area we should support both during and after cancer treatment is the gut. But what do the treatments do to the gut?
Please keep in mind that dysbiosis (loss of balanced microbial diversity) is present in people who develop cancer and gets worse as a result of treatment. For health to be restored, the microbiomes (there are more than one) in the body need to be balanced, and microbial diversity needs to occur.
Here’s what happens to the gut as a result of treatment.
Chemotherapy: Up to 87% of patients experience gastrointestinal side effects because chemo reduces gut microbial diversity, lowers butyrate producers, and increases harmful species, disrupting systemic repair.
Cancer Surgery: Beyond structural changes, surgery itself, plus anesthesia, antibiotics, and stress responses, drives gut dysbiosis, reduces beneficial microbes, and impairs barrier function, regardless of the surgical site.
Immunotherapy: Response rates are linked to the microbiome, with higher Akkermansia, Faecalibacterium, and Bifidobacteria improving outcomes, while dysbiosis increases risk for systemic immune-related colitis and diarrhea.
Radiation Therapy: Whether targeted to the breast, pelvis, or elsewhere, radiation lowers microbial diversity and SCFA producers, worsens pre-existing dysbiosis in the irradiated tissue’s microbiome, and increases reliance on the gut microbiome for repair, with 5–15% of patients developing chronic enteropathy.
I put the citations for this information below to show that the symptoms after cancer treatment are well-known.
Remember that the gut microbiome is connected to other microbiomes and plays an essential role in communicating with the rest of the body to help it function. That’s why it is so essential and also why it‘s so complex. Deciding to work on gut health is easy, but takes time and patience.
I created a small mini-course called After Cancer Recovery. If cancer recoverers don’t know that some regions of the body are more likely to be out of balance as a result of the treatment, this mini-course is designed to bring awareness.
It does not have all the answers—how could it? We are all different. But it does provide enough information to give people a starting point and some simple suggestions. This can help them be more informed when searching about their issues or talking to a practitioner for more help.
Click here if you’d like to purchase After Cancer Recover - the mini-course
I just added the 3-Step Framework Gut Health Guide to provide more gut information, as this is one of the first places to focus on getting the best long-term results.
References:
Han X, et al. Chronic pain among cancer survivors in the United States: JAMA Oncol. 2019;5(6):966-968.
van den Beuken-van Everdingen MHJ, et al. Prevalence of chronic pain in cancer survivors: systematic review. J Pain Symptom Manage. 2007;34(6):605-618.
Janelsins MC, et al. An update on cancer- and chemotherapy-related cognitive dysfunction: current status. Semin Oncol. 2011;38(3):431-438.
Ahles TA, Root JC. Cognitive effects of cancer and cancer treatments. Annu Rev Clin Psychol. 2018;14:425-451.
Seretny M, et al. Incidence, prevalence, and predictors of chemotherapy-induced peripheral neuropathy: systematic review and meta-analysis. Pain. 2014;155(12):2461-2470.
Staff NP, et al. Chemotherapy-induced peripheral neuropathy: a current review. Ann Neurol. 2017;81(6):772-781.
Montassier E, Gastinne T, Vangay P, Al-Ghalith GA, Bruley des Varannes S, Massart S, et al. “Chemotherapy-driven dysbiosis in the intestinal microbiome.” Aliment Pharmacol Ther. 2015;42(5):515–28.
Stringer AM. “Interaction between host cells and microbes in chemotherapy-induced mucositis.” Nutrients. 2013;5(5):1488–99.
Zhong Y, Xu F, Wu J, et al. “Chemotherapy-induced diarrhea is associated with changes in gut microbiota composition in patients with colorectal cancer.” Front Oncol. 2021;11:641646.
Olivas A, et al. “Surgical stress response and its impact on the gut microbiome.” Clin Nutr ESPEN. 2020;40:18–25.
Ohigashi S, Hoshino Y, Ohde S, Onodera H. “Changes of the intestinal microbiota, short chain fatty acids, and fecal pH in patients with colorectal cancer.” Dig Dis Sci. 2013;58(6):1717–26.
Routy B, Le Chatelier E, Derosa L, et al. “Gut microbiome influences efficacy of PD-1–based immunotherapy against epithelial tumors.” Science. 2018;359(6371):91–7.
Gopalakrishnan V, et al. “Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients.” Science. 2018;359(6371):97–103.
Wang A, Ling Z, Yang Z, et al. “Radiation-induced dysbiosis in the gut microbiota leads to increased bacterial translocation and systemic inflammation in mice.” Radiat Res. 2015;183(4):406–17.
Nam YD, Kim HJ, Seo JG, Kang SW, Bae JW. “Impact of pelvic radiotherapy on gut microbiota of gynecological cancer patients revealed by massive pyrosequencing.” PLoS ONE. 2013;8(12):e82659.
Reis Ferreira M, Andreyev HJN, Mohammed K, et al. “Microbiota- and radiotherapy-induced gastrointestinal side-effects (MARS) study: a large pilot study of the microbiome in acute and late-radiation enteropathy.” Clin Cancer Res. 2019;25(18):5447–57.