Medical Cannabis Use in Oncology

Excerpt

Medicinal marijuana (Cannabis sativa) has become a topic of great debate within the oncology literature. There have been several proposed uses of cannabis by clinicians and researchers alike. As of April 2021, medical marijuana use has become legal in 36 states, and recreational use has been approved in 15 states and Washington, DC. With the increasing use of marijuana, it will likely become commonplace for patients to seek advice from medical providers in terms of potential therapeutic use. Clinicians should know the potential uses and side effects associated with marijuana to educate patients properly.

The history of cannabis within the medical community dates back to the 19th century when Dr. William Brooke O'Shaughnessy first published his data on the pharmacology and toxicology properties of cannabis. He found it to be a powerful analgesic, anti-convulsant, and muscle relaxant through his experimental treatment of patients suffering from rheumatism, cholera, tetanus, and seizures. In 1964, Gaoni and Mechoulam successfully identified the active elements that comprised cannabis, namely cannabinoids such as delta-9-tetrahydrocannabinol (THC). This ultimately led to the discovery in the 1990s of the human endogenous molecules, Anandamide (ADA) and 2-arachidonoyl-glycerol (2-AG), that play a role in the endocannabinoid system by acting on cannabinoid receptors 1 and 2.

As of January 22, 2021, the U.S. Food and Drug Administration has approved one purified form of CBD for seizure treatment as well as three medications that contain either dronabinol (THC) or nabilone (synthetically derived form of THC) for therapeutic use. Exogenous cannabinoids, such as THC and cannabidiol (CBD), and their effect on the endocannabinoid system will be discussed below regarding their role in oncology with chemotherapy-induced nausea/vomiting (CINV), analgesia, cachexia, and tumor suppression.