Evaluating the Use of Cannabinoids in a Palliative Cancer Care Setting
For many patients, the concept of palliative care often carries with it a negative connotation, conjuring ideas and fears of the end of life. However, the purpose of palliative care is to improve the patient experience and reduce suffering in all areas of life, including physical, emotional, psychological, and spiritual well-being. In fact, incorporating palliative care into cancer management has the potential to not only improve quality of life, but may also prolong survival (Temei, NEJM, 2010; Ferrell, J Clin Oncol, 2017).
The physical ailments experienced by cancer patients vary widely based on the individual, the type and stage of cancer, and the choice of therapy. Three of the most common and perhaps most debilitating complaints addressed by palliative care are chronic pain, chemotherapy-induced nausea and vomiting, and severe body wasting (Reeve, JNCI, 2014). Although efforts have been made to ameliorate these symptoms, many patients do not achieve adequate relief. The need for new therapeutics to improve these debilitating symptoms has gained increasing attention in recent years.
Opportunity to Improve Upon the Standard of Care
Many aspects of cancer palliation would benefit from improvement. A large proportion of patients never achieve adequate control of their cancer symptoms and many palliative therapies offered are not without their own side effects. For the most part, there is already compelling evidence to suggest that cannabinoids are both safe and efficacious in the management of cancer symptoms.
Two cannabinoid therapeutics, dronabinol and nabilone, are already FDA-approved in the United States for the treatment of chemotherapy-induced nausea and appetite stimulation. Furthermore, a recent study conducted in Washington State, where both medical and recreational marijuana is legalized, demonstrated that up to 24% of cancer patients elected to use cannabis for management of their physical symptoms, including pain, nausea, and loss of appetite (Pergam, Cancer, 2017).
One advantage of cannabinoid-based adjunctive therapies is the potential for synergism. To this point, in an observational study of advanced cancer patients experiencing significant pain and other symptoms, those using nabilone experienced improvement in their symptoms while also exhibiting a decreased use of pain medications, including opiates, as well as anti-emetics (Maida, J Support Oncol, 2008). Thus, the use of cannabinoids may reduce the minimum effective dose of first-line therapies and consequently minimize the potential for adverse effects. Although the two FDA-approved cannabinoids support the efficacy of this class of drugs, they are rife with negative side effects due to their psychoactive properties (Smith, Cochrane Database Syst Rev, 2015; Tramer, BMJ, 2001). The development of more targeted cannabinoid therapies may help maximize therapeutic benefit, while minimizing off-target effects.