This transcript has been edited for clarity. For more episodes, download the Medscape app or subscribe to the podcast on Apple Podcasts, Spotify, or your preferred podcast provider.
Kathryn J. Ruddy, MD: Hello. I’m Dr Kathryn Ruddy. Welcome to season three of the Medscape InDiscussion: Cancer Survivorship podcast series. Today, we’ll discuss how cannabis is used by patients with cancer and what research is ongoing pertaining to medicinal mushrooms.
First, let me introduce my guest, Dr Stacy D’Andre. Dr D’Andre is a board-certified medical oncologist with a special interest in integrative medicine. She’s an assistant professor of oncology at Mayo Clinic in Rochester, Minnesota. Her clinical focus is on helping patients with lifestyle changes, including improving diet, exercise, sleep, and stress reduction. She has a special interest in medical cannabis and medicinal mushroom research.
Dr D’Andre, welcome to the Medscape InDiscussion: Cancer Survivorship podcast. I want to start by asking you what medicinal mushrooms are, and how psychedelic mushrooms are related to this. Are they just a type of medicinal mushroom? Can you tell us more about all of this?
Stacy D. D’Andre, MD: Sure. Medicinal mushrooms are mushrooms that are consumed for their medicinal properties. These are consumed either in a food form or in a supplement form, like a tea or an extract. Sometimes they come as a powder. These types of mushrooms have been widely used in Asia as an adjunct to cancer treatment. There are many types. You’ve probably heard of some of them, like reishi mushroom, turkey tail mushroom, shiitake, maitake, and lion’s mane. There are over a hundred different types. They all have different properties. The mushrooms are so interesting because they contain these polysaccharides called beta-glucans, which are immune stimulants. They have a lot of interesting properties, including anti-inflammatory properties and antioxidant effects. We and others are studying turkey tail for its activity for breast cancer. We also have a trial going on at Mayo using reishi mushroom to treat women with aromatase inhibitor-induced fatigue and arthralgias.
Psilocybin is a different kind of mushroom, and this is more of a psychedelic mushroom. These types of mushrooms are very different in their properties, and they have been used for centuries by Indigenous people for their spiritual and ceremonial use. Currently, psilocybin is a Schedule I, so very similar to cannabis. It’s difficult to study. We will talk a little more about some of the challenges that we’ve had. Psilocybin has shown promise in treating patients with treatment-resistant depression, major depressive disorder, and cancer-related anxiety and depression. These psilocybin medicinal mushrooms are also being studied for addiction, pain, and existential distress. There are lots of interesting things happening with mushrooms.
Ruddy: I’d love to hear more about this. Are there ongoing trials that are studying psilocybin in the US?
D’Andre: Yes. There are different studies going on across the country, and of course, there are some challenges with conducting this type of research because it is Schedule I. You have to get a special license from the Drug Enforcement Administration, a Schedule I license, to be able to perform this type of research. Nonetheless, people are conducting lots of research trials for patients, especially with depression, and for cancer-related anxiety, and we are in the process of getting our own clinical trial for existential distress up and running.
Ruddy: I can imagine that could be very important. Are there specific side effects that are known to be related to either the medicinal mushrooms in general or specifically psilocybin that are relevant to your work?
D’Andre: Yes. We’ll start with psilocybin. Psilocybin definitely has side effects. These can include, after ingestion of these types of mushrooms, tachycardia or hypertension. Often during clinical trials, you’re monitoring these for many hours, and the effect of these mushrooms lasts for 8-10 hours. It’s a long day. People do have what they call “a trip” because they often will have a mystical experience. They’ll actually go somewhere, and they have hallucinations; they can have time and perception alterations or illusions, but this is part of the process. It’s a very complex procedure. When we do this type of clinical trial, you have to provide counseling before and after the session. It’s very labor-intensive.
Medicinal mushrooms, like reishi and some of these other mushrooms, can have some side effects. They are not psychedelic, so some of the more common side effects include mild GI symptoms. They will often lower blood pressure and blood glucose. Sometimes we do get into drug interactions that we have to be aware of. Also, with some of these medicinal mushrooms, we don’t use them in conjunction with immunotherapy because they are immune-stimulating. So, more research is needed in that area, but we err on the side of caution.
Ruddy: Interesting. You mentioned a particular study related to breast cancer. Are there any hormonal effects of these mushrooms?
D’Andre: Not that I know of. They don’t have any estrogenic type of activity or any other androgenic type of activity.
Ruddy: Let’s turn to cannabis, which is obviously a big topic in recent years. Can you tell our audience about how cannabis is currently being used by patients with cancer?
D’Andre: The estimates from survey studies show that about 25% to up to close to 60% of patients with cancer are using cannabis at some point during their journey. Some patients are using this for symptom management during their therapy. Some people will use it for lingering symptoms. Importantly, some patients may not tell their care team, so it’s always important to ask if your patients are using cannabis.
What we find cannabis useful for, and what many patients use it for, is for nausea that is not responding to other medications, and for noncancer pain such as neuropathy. The evidence for appetite is actually pretty weak, but the studies have been done with oral agents, and in my practice, my patients report that the inhaled form of cannabis tends to stimulate appetite a little bit better, but we definitely need more research in that area. A lot of patients are using cannabis for insomnia, and there’s really not a lot of data. Most of the trials have included insomnia as a secondary endpoint, so you can imagine if a patient has pain or nausea, they don’t sleep well often, and if you treat those symptoms, they sleep better. We’re working on a clinical trial to specifically look at insomnia as a primary endpoint.
Ruddy: Interesting. Based on that, I’m guessing that sedation is one possible side effect. What other side effects are you seeing in your patients who are using cannabis?
D’Andre: The side effects from cannabis are largely from the delta-9-tetrahydrocannabinol (THC) content. The THC is the compound in cannabis that creates the euphoria or the high feeling. The side effects are dose dependent. The higher the dose, the more you’re going to feel these things. So you can feel some disorientation, some imbalance.
There can be some variable effects on heart rate and blood pressure. Often, the inhaled forms are more likely to cause some of these symptoms, such as tachycardia or conjunctivitis, coughing, and bronchitis. I think it’s important to note that some patients get more anxiety when they use THC, so it’s something to be mindful of.
We don’t often use cannabis to treat anxiety or depressive symptoms. People also think that cannabidiol (CBD) is pretty benign. You can buy it over the counter anywhere now, but that’s actually not true. When you consume higher doses of CBD, you can have nausea, vomiting, diarrhea, and increased liver function tests.
Ruddy: Do you worry about medication interactions?
D’Andre: Yes. Cannabis can interact with many different medications. We think this is a dose-dependent effect as well. The most common interactions include warfarin and some seizure medications. But through CYP interactions, there can be lots of different ones. It’s really important to check with the pharmacist. There’s really no contraindication in regard to medications; you may need to adjust the doses of the other medications and be mindful of the interactions.
Ruddy: Is there an increase in fall risk? And is there any age cutoff over which you don’t recommend cannabis?
D’Andre: That’s a great question. There is a fall risk, especially in our older patients or patients who may have neuropathy or dizziness at baseline. I don’t think there really is an age cutoff. It’s more of an issue of ensuring the patient’s safety. If we start cannabis in an elderly patient or somebody who is not completely stable in regard to their balance, we start with a really, really small dose. That would be something on the order of one to two milligrams of THC. The mantra is, we start low and we go slow with titration. I really insist that my patients have family members with them to ensure that if they do have to get up at night, they have assistance getting up. It definitely is a concern and something to be mindful of.
Ruddy: Dr D’Andre, could you explain what reservations or concerns people may have about this topic?
D’Andre: Sure. Some patients are concerned that cannabis is still federally illegal, and so they worry about the legality of using cannabis even if it is medically or recreationally legal in their state. It is a very complex landscape for patients to navigate. Some patients have concerns about the quality of the products that are out there. That’s another important piece. Patients are also concerned about the stigma of cannabis. Many people think that this is a drug of abuse, and it certainly has been and can be. I think it’s important to have these conversations with patients, especially when we are using this in a medicinal fashion.
Ruddy: What are some of the reservations of clinicians? Are people concerned about a lack of data or uncertainties about medication interactions? What are you hearing, Dr D’Andre?
D’Andre: Many providers are really uncomfortable discussing cannabis with patients because of a lack of education. You really have to take the extra steps to be able to speak on this topic, and there are courses available out there for people who are interested. There is a lack of rigorous research, mainly because this is still a Schedule I drug, which makes it very challenging to do high-quality, large, randomized trials. I think it’s a combination of a lack of education, not understanding the legal landscape, and the lack of research.
Ruddy: If a clinician is listening to this episode right now and they want additional information on the use of cannabis or medicinal mushrooms in oncology, what resources are out there for them?
D’Andre: A great resource for cannabis education is the Society of Cannabis Clinicians. They have a pretty detailed course on cannabis. Another resource is a simpler one called healer.com. Both of them provide an excellent background in cannabis use, so I would recommend those for the cannabis portion. For the mushrooms, it’s hard to point to a specific course, but certainly the University of Arizona’s integrative program does have modules on integrative oncology. They have covered some of the data on mushrooms and psilocybin. There is an annual psychedelic conference that, if you’re interested in learning more about psychedelics, would be a good place to look. We are also just launching our integrative oncology course through Mayo’s continuous professional development. And that course also discusses, in pretty good detail, cannabis and mushrooms, both medicinal and psilocybin.
Ruddy: That’s really interesting. Thank you. Can you speak to the fact that some patients are interested in cannabis as a treatment for cancer rather than just as a symptom management strategy?
D’Andre: Yes. This is actually pretty common. The bottom line with that is, we just don’t have data. We have no large randomized trials that show any benefit. And again, going back to the point that Schedule I research is challenging, there certainly are anecdotal reports and case reports of patients using high doses of THC to treat their cancer. But that is really not enough for us to recommend such treatments, and we don’t know — is it the THC? Is it the CBD? What dose should we use? What formulas should we use? We really have a long way to go before we know these answers about cannabis as an anticancer agent.
Ruddy: I imagine there could be problems with that. If patients choose to pursue cannabis as a therapy, it could interfere with some of the standard proven therapies that we as oncologists might be recommending, or it might actually interfere with a standard effective therapy.
D’Andre: Yes, that could be possible, especially with some of the doses that are recommended on the internet. They’ll push the doses very high with THC, and certainly that can have the potential for interactions and side effects.
Ruddy: That makes sense. To finish up, can you say anything about access to cannabis? Are there differences from state to state or country to country in regard to this? And are there any legal concerns that patients have to consider with the use of cannabis?
D’Andre: It’s a very complex landscape. Currently, all the states have different laws regarding cannabis use, and medical cannabis is legal in most states. Only 12 states do not have a medical program. The majority have a medical program where you need to be certified. And you have to have a qualifying condition. That qualifying condition could be chronic pain, or it could be a cancer-related symptom. That varies from state to state as well. In regard to recreational cannabis, 24 states currently have recreational use as well. So it’s pretty much open for anyone to buy cannabis.
In other countries, it’s highly variable. Some countries, like Canada, have fully legal, recreational, and medicinal use. In other countries, it’s really strictly illegal. In many countries in the Middle East, it’s against the law and carries stiff penalties. It’s really important to know what’s going on, especially in regard to travel as well. We do not recommend traveling across state lines. We don’t recommend flying with it because it’s still federally illegal, and certainly would not go out of the country with it.
Ruddy: Thank you so much for sharing all of this very important information, Dr D’Andre. Today we’ve talked to Dr D’Andre about when cannabis may be useful for treating specific symptoms in patients with cancer. We’ve learned from her about medicinal mushrooms, including psilocybin, and how these are being studied as treatments for oncology. Thank you for tuning in. Please take a moment to download the Medscape app to listen and subscribe to this podcast series on cancer survivorship. This is Dr Kathryn Ruddy for the Medscape InDiscussion: Cancer Survivorship podcast.
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Resources
Mushroom-Derived Bioactive Compounds Pharmacological Properties and Cancer Targeting: A Holistic Assessment
Phase 1 Clinical Trial of Trametes versicolor in Women With Breast Cancer
Reishi Mushroom for Fatigue and/or Arthralgias for Patients With Breast Cancer on Aromatase Inhibitors
Review of Psilocybin Use for Depression Among Cancer Patients After Approval in Oregon
Adverse Events in Studies of Classic Psychedelics: A Systematic Review and Meta-Analysis
Symptom Improvements and Adverse Effects With Reishi Mushroom Use: A Cross-Sectional Survey of Cancer Patients
Cannabis Use Among Recently Treated Cancer Patients: Perceptions and Experiences
Understanding Feeling “High” and Its Role in Medical Cannabis Patient Outcomes
Metabolism and Liver Toxicity of Cannabidiol
Interaction Between Warfarin and Cannabis
Society of Cannabis Clinicians