By some estimates, upwards of 90 percent of patients with an advanced cancer diagnosis suffer from chronic pain. Cancer-related pain can stem from the progression of cancer itself or from the various surgeries, treatments, and procedures deployed to combat it. While opioids are the most convenient option, increasingly patients are asking their oncologist about cannabis for cancer-related pain.
With growing legal, medical, and social support for cannabis in medicine, what is the current status of cannabis for cancer-related pain? There have been several small but well-controlled studies exploring this potential opioid alternative. It’s also one of the most widely approved qualifying conditions for a cannabis recommendation in the US.
The following breakdown is a quick summary of some of the most recent and interesting developments surrounding cannabis as a treatment for cancer pain.
From Patient Preference to Oncologist Recommended
Patient surveys and case studies have long documented a growing patient preference for medical cannabis as a conjunctive treatment for cancer-related symptoms. Cancer is now one of the most common qualifying conditions among states with medical cannabis programs in the United States.
While opioids remain the most accepted and prescribed method of treating cannabis pain in modern medicine, patient surveys almost always indicate that patients prefer cannabis as a pain treatment. Scientific study is finding strong evidence for cannabis in oncology to reduce intractable pain, reduce nausea and vomiting associated with chemotherapy treatments, and for many, improve quality of life.
As per one patient assessment published in 2017, “Ninety-seven percent of the sample ‘strongly agreed/agreed’ that they are able to decrease the amount of opiates they consume when they also use cannabis, and 81% ‘strongly agreed/agreed’ that taking cannabis by itself was more effective at treating their condition than taking cannabis with opioids.”
A 2017 investigation reported “high rates of active use across broad subgroups” among cancer patients in places with legal access. However, this report also noted, “Cancer patients desire but are not receiving information about cannabis use during their treatment from oncology providers.” But this oncologist aversion to cannabis seems to be slowly changing.
In 2018, for instance, the National Council of State Boards of Nursing published a set of guidelines for nurses in response to the growing number of cancer patients choosing to self-treat with cannabis.
It made clear that “regardless of existing evidence, individuals are using cannabis, and nurses will care for these patients,” and thus, they need to understand the basics of cannabinoid therapy. Several national physician organizations (like the Canadian Family Physicians) have also issued guidance on prescribing medical cannabis for cancer.
Patients are demanding more information from their oncology team about the benefits, risks, and effectiveness of cannabinoid conjunction treatment. A national physician survey from 2018 suggests cannabis is breaking into the mainstream for cancer and cancer treatment-related side effects, like pain.
According to this survey, a full 80 percent of oncologists discussed medical cannabis with their patients, while 46 percent recommended it clinically. Patients are demanding answers about cannabis, and physicians are trying to keep up.
The Entourage Effect May be Applicable for Cancer-Related Pain
In 2010, researchers working out of the United Kingdom designed a multicenter, double-blind, randomized, placebo-controlled, parallel-group study. Well controlled, this study worked with a total of 177 patients with intractable cancer-related pain.
According to their assessment of patients before entering this study, most had cancer pain from mixed pathophysiology, bone pain, and neuropathic pain. The researchers examined changes in pain using a numerical pain score.
Researchers gave one-third of the group an extract with THC:CBD (2.7 mg THC: 2.5 mg CBD), another third straight THC (2.7 mg THC), and finally, the last group a placebo.
Over a two-week period, the participants self-administered the cannabinoids (or placebo) as an oral spray. Patients were allowed to increase the frequency of dose as much as needed up to a predetermined maximum.
The researchers discovered a statistically significant reduction in pain among patients receiving the THC:CBD extract compared with the placebo, but this was far less noticeable with straight THC. In fact, twice as many patients taking the cannabinoid combo than the THC extract experienced a 30 percent reduction in pain scores.
Notably, there were no safety concerns with any groups during the trial, with both cannabinoid medications well tolerated by all. Side effects from the cannabis therapies were expected, such as sleepiness, dizziness, and nausea.
The striking pain improvements with the THC:CBD extract compared with the THC extract could be evidence for the Entourage Effect. The research further explained this synergistic benefit in their discussion. They suggested, “CBD may enhance the analgesic potential of THC by means of potent inverse agonism at CB2 receptors, which may produce anti-inflammatory effects, along with its ability to inhibit immune cell migration.”
It may also be possible that CBD helps mitigate some of the challenging intoxicating effects of THC through antagonism at CB1 receptors.
Cannabis for Cancer Pain Moving into Oncology
With the growing number of well-controlled trials and booming patient demand, cannabis is making its way into modern oncology discussions. It only makes sense, considering medical cannabis is generally well-tolerated, less dangerous than opioids, and often preferred by patients.
As legalization has spread around the world and scientific understanding of cannabis for cancer pain expands, cannabis as an alternative treatment to cancer pain is an evolving trend in oncology.