Patients' Perceptions of the Efficacy, Safety, and Quality of the Evidence of Medicinal Cannabis: A Survey of Australian Cancer Patients.

Introduction: Despite the increased demand for medical cannabis (MC), MASCC guidelines state that there is insufficient evidence of its efficacy and safety. Although research has explored medical professionals' perceptions of MC, there is to our knowledge minimal research exploring patients' perceptions, particularly in an Australian cancer setting.

Methods: A survey of Australian cancer patients attending oncology outpatient clinics was performed. Patients were ≥ 18 years and had a confirmed diagnosis of cancer (solid or hematological).

Results: A total of 413 patients were approached between April 2019 and March 2020 out of which 82% (350) consented to participate. A total of 19% (67/350) were using MC. Despite being used for symptom control, such as pain (61%), and, in some cases for perceived anticancer activity (12% to cure, and 16% to slow the cancer), only a minority of users believed that the evidence was of high quality for these indications (28% for physical benefits and 29% for anticancer activity). Nonusers were even more skeptical of the evidence for these indications (17% and 11%, respectively). Only a minority of patients (31% of users and 8% of nonusers) accessed information on MC from clinicians. Most instead relied on resources such as TV, friends, family, social media, and websites.

Conclusion: This study demonstrates current real-world cancer patients' perceptions on the evidence for MC, the sources of information used to shape their health beliefs, and compares users to nonusers. The results highlight the need for treating teams to combat potential misinformation that patients may be accessing about MC and provide information on treatments with stronger evidence.