Last updated: Jan 23, 2020 | USA
PUBLISHED : 23 JAN 2020 - 13:31
Marijuana won’t make cancer disappear, but it can make living with it much more bearable. Doctors need to start asking the right questions.
Cancer is something most of us don’t like to think about, but it’s also something the vast majority of us are going to have to face sooner or later.
Because North Americans are generally living longer, it’s estimated as many as 1 in 2 of us will face a cancer diagnosis in our lifetimes. Even if we’re lucky enough not to have it happen to us, odds are it will affect a loved one or friend.
Even though treatments for cancer are improving by leaps and bounds (in the last couple of years, drugs called immunotherapeutics have shown huge promise against tough-to-treat ailments like pancreatic cancer) it’s important to understand treatment options.
Treating cancer: chemo, radiation and relief
Most cancer treatment plans are focussed on two methods: using radiation to kill tumours directly and using chemical agents – chemotherapy – to trick cancer cells into destroying themselves.
Both of these methodologies have advantages and drawbacks, and it’s likely an individual treatment plan will involve both elements.
Unfortunately, because both radiation treatments and chemotherapy can be quite harsh on the body, they can result in significant side effects: nausea and vomiting; constipation and diarrhea and neuropathy, which can be painful.
But, just as there are exciting new drugs on the horizon to tackle even the most stubborn cancers, a newly-legalized class of compounds can bring much to bear on dealing with the symptoms of cancer treatment: cannabis products.
There’s lots of data out there showing the active ingredients in marijuana can make the cancer treatment phase more bearable. This is due to the analgesic properties of THC and CBD; their anti-nauseant effects and the ability of cannabinoids to stimulate appetite.
Cannabis conundrum: Can it kill cancer directly?
However, a lot of misinformation and pseudoscience is floating around about what exactly cannabis products can contribute to treating cancer.
One pseudoscientific idea that gets a lot of traction on social media is that the active ingredients in cannabis, including THC, CBD and other terpenes, can kill or alter the metabolism of cancer cells directly.
Products making such claims should be treated with a healthy dose of skepticism, especially when dealing with a situation that’s as serious as a cancer diagnosis.
While several studies have shown the ingredients of cannabis can alter some biological markers in cancer cells, these analyses have been carried out in test tubes, and the effects of drugs on living tissues is much different.
What is clear is that cannabis does have a place in the arsenal of tools that’s now available to help in the battle against cancer, whether to manage the progression of symptoms or to effectively treat breakthrough pain – a very tricky and tough-to-treat kind of pain associated with advanced cancers.
Evidence of efficacy
In a landmark study, published in 2001 in England, the therapeutic effects of cannabis on cancer treatments were thoroughly investigated.
It emerged that cannabis is effective in treating pain and nausea; that it stimulates the appetite and leads to a decrease in intraocular pressure – the pressure within the eye – revealing it as a potential cure-all for glaucoma, which can affect those undergoing oncological procedures.
So, we do have evidence that cannabis can be of great help within the framework of cancer treatment — but what is the best way to implement that practice, especially when marijuana and marijuana-derived products remain legally dubious in many places?
Before we discuss how to make sure we all have access to the cannabis products we need for quality cancer care, let’s briefly discuss why cannabis matters in the first place. Believe it or not, it has a lot to do with evolution.
Why does cannabis make us feel better?
The main reason cannabis has an effect on us is because we have an endocannabinoid system. This is a series of cellular receptors, scattered on the surfaces of cells in different tissues around the body — from brain to muscles to liver.
When exposed to some of the different chemicals in cannabis — from THC to CBD — these receptors are activated, resulting in a number of biological changes, from decreased inflammation to changes in gene expression patterns.
In fact, the precise biological changes elicited by the chemicals in cannabis are still a subject of much debate. We know cannabinoid receptors are found throughout the body, especially in parts of the body that are known to regulate immune responses.
What is known for sure is that we possess a deep connection to plants; they can produce changes in our bodies that affect us at the DNA level. The fact that we can take advantage of these deep connections to produce desirable results in our bodies is compelling evidence we need to take cannabis seriously as part of a treatment regime for any serious illness.
Cannabis: Treating cancer-related illnesses, back to antiquity
Cancer is one of the most ancient diseases, and many cultures have used cannabis to treat its effects, stretching back to antiquity.
Plantations of hemp in what is present-day Taiwan led to the cultivation of cannabis more than 10,000 years ago. It didn’t take long for villagers to recognize the plant they were using primarily for building material had therapeutic benefits.
“The use of cannabis in medicine was probably a very early development,” says one renowned Chinese botanist.
The early Chinese surgeon Hua Tuo is thought to have been the first physician to exploit the anaesthetizing properties of cannabis as a part of his medical practice in that era. He chemically treated the cannabis plant to reduce it to a powder, then dissolved this mixture in a glass of wine that was administered to patients in advance of potentially painful treatments.
Cannabis still retains a place of pride amongst the 50 fundamental herbs that make up the backbone of a traditional Chinese medicine practice.
Risks and benefits
What exactly are the risks of using cannabis to treat cancer?
Even though the negative effects of using marijuana are unlikely to appear at the minimum doses required for clinical efficacy, they are still important to be aware of, especially for people who have health problems.
The main negative effects are cognitive: there’s evidence regular marijuana use can lead to an increased risk of schizophrenia and paranoia.
It can also worsen symptoms of clinical depression, which is often a diagnosis found within cancer patient populations.
Cannabis is also known to cloud judgement and to distort our perception of time. Further, there’s the potential for addiction – 1 in 10 marijuana users are known to develop some kind of a dependency.
However, for those facing a daunting cancer treatment regime or for those in palliative care, the risk of addiction is largely outweighed by the pleasant cognitive effects of cannabis consumption.
On the physical side, marijuana can increase appetite, which may be a problem for people who are overweight, but since many people going through radiation treatments or chemotherapy suffer from nausea or reduced appetite, this effect is a plus.
The main thing to be worried about is the effect of cannabis on heart rate. Studies show consuming mairjuana can increase the work the heart does by as much as 70%. This is usually not a problem for most people, but those suffering from heart conditions such as tachycardia would be advised to explore using cannabis with caution.
All things considered, cannabis is a much safer drug than some others used in cancer treatment – especially opioids, which have a high risk of addiction and accidental overdose.
Drugs and discoveries
If you want the therapeutic benefits of cannabis for treating cancer-related illness, but you live in a part of the U.S. where marijuana products are prohibited, there are several pharmaceutical solutions.
Dronabinol is a capsule containing THC that’s FDA approved to treat nausea and vomiting associated with chemotherapy drugs.
In addition, a drug called Nabilone is a synthetic cannabinoid (synthesized in a lab, not extracted from the marijuana plant) that is taken orally to treat nausea and vomiting caused by chemotherapy.
It seems silly that a plant that is legal in several states and in some countries is prevented from getting into the hands of consumers who need it as part of their medical care strategy, but that’s unfortunately often the case in parts of the world where regulation is not consistent.
A question of access
Dr. Hance Clarke, a staff anesthesiologist and the director of pain services at Toronto General Hospital, is a keen supporter of removing those limitations and providing access to cannabis during cancer treatment.
He’s dismayed at a lack of institutional knowledge about the benefits cannabis can provide in a clinical setting versus the risks – which he says are vastly overblown. He says North America’s reluctance to embrace cannabis therapies speaks to a regressive mindset.
“When the EU puts out a notice to say, within three years, all Europeans must have access to cannabis products for cancer treatment, that sends a clear message,” says Clarke.
According to Clarke, because physicians generally tend to be conservative – waiting to see if an overwhelming amount of evidence points toward a therapeutic benefit for a drug before prescribing it – this reluctance tends to limit their patients’ access to care.
This can be especially frustrating if the potential benefits from a treatment outweigh the risks to a vast degree, meaning patients are suffering from a reduced quality of life for no reason other than their doctors are uninformed.
Complicating matters is the ingrained notion that if a drug is illegal in some jurisdictions, or has only become legal recently, a stigma is attached to prescribing it.
This leads to doctors not talking about cannabis as a treatment at all. Thus, patients under their care may not have the opportunity to find out about it.
Doctors deserve data
One of the reasons for this hesitation is a lack of understanding around the safety and efficacy of cannabis in a cancer context.
“It takes time for people to grasp what is a safe and effective drug,” says Clarke. “They also don’t grasp the subtle level of … affinity. They’re thinking about getting high, which is six times the dose you need for a clinical effect. There’s been interest [in cannabis treatment], but there’s no education.”
Providing that education is a mission for Clarke. “The fact remains,” he says, “less than 10% of physicians have ever prescribed cannabis,” in Canada.
How can these numbers be raised? How can those responsible for our care be made aware of the benefits?
“There’s a part of me that was doing harm for not considering cannabis earlier,” says Clarke.
The main shift for him began when his patients started asking him about it in droves. He tells a heart-wrenching story about treating a friend of a friend who came to him asking about access to marijuana after a devastating stage 4 pancreatic cancer diagnosis.
He agreed to change her opioid medications, but she died before the changes could be implemented. He wondered if he could have allayed some of her suffering if he had taken cannabis as a treatment more seriously.
Clarke says that while he doesn’t blame himself for his patient’s suffering, he wished he had been more flexible in trying to understand what cannabis could offer her.
With the legalization of marijuana in Canada arriving in October 2018, and a subsequent explosion in patient interest in cannabis, that flexibility may be forced onto physicians whether they are ready or not.
‘Doorstep of change’
“We are now at the doorstep of change,” says Clarke. “Patients are more interested. Doctors are saying: maybe I do want to be a part of it.” So, what can physicians do right now to get ahead of the oncoming tide of inquiries about cannabis from their patients?
“Get familiar with the products that are out there,” says Clarke. “The evidence will come – the science is being done. But today we have a population of patients that need our guidance. We certainly have evidence that [cannabis works] for pain. There are areas where we have good evidence to back these things.”
As that evidence for the efficacy of cannabis in treating cancer-related illness begins to swell, it’s hopeful that doctors will set aside their prejudices against marijuana and move toward a future where access to a useful and needed suite of medications can be had by all who need it.