A Comprehensive Review of Cannabis in Patients with Cancer: Availability in the USA, General Efficacy, and Safety

As the legalization of medical cannabis continues across the USA, oncology care providers will be increasingly asked to provide recommendations regarding its use in the cancer setting. In this article, we review recent literature that analyzes cannabis use specifically in patients with cancer and provide an accessible guide for clinicians, researchers, and patients.

We aimed to answer questions about the availability of cannabis in the USA, the trials supporting its use in the cancer setting, and the important factors to consider related to safety. Thirty states plus the District of Columbia have established comprehensive medical cannabis programs, each with different regulations and products available. In June 2018, Epidiolex, a cannabis extraction product containing 99% CBD, was approved to treat refractory seizures; however, whole-plant products and non-prescription extraction products dominate the market. Recent randomized, placebo-controlled studies of nabiximols (Sativex) in patients with refractory cancer-pain have largely shown no significant benefits. Conversely, large observational studies suggest patients with cancer using cannabis report significant improvement of many common symptoms. Cannabis use appears well tolerated, with few serious adverse effects reported. Though prospective clinical trials are needed to provide the robust data required to establish the proper role of cannabinoid and cannabis-based therapy in cancer patients, physicians can draw upon the knowledge currently available to have informed discussions with their patients.