Most Cancer Patients Using Medical Cannabis Know the Evidence Is Weak | Research

The takeaway

Among 350 Australian cancer patients, 19% used medical cannabis, mostly for pain, but only 28% of users believed the evidence for physical benefits was high quality — and most got their information from non-clinical sources.

oncologists, supportive care specialists, cancer patients considering cannabis, medical educators

What the researchers found

19% (67/350) of cancer patients were using medical cannabis, primarily for pain (61%). Some used it believing it could cure (12%) or slow cancer (16%). Only 28% of users and 17% of non-users rated the evidence for physical benefits as high quality. Only 31% of users and 8% of non-users got MC information from clinicians. Most relied on TV, friends, family, social media, and websites.

Why it matters

Despite widespread cannabis use among cancer patients, most are aware that evidence quality is limited yet still use it. The disconnect between information sources (mostly non-clinical) and clinician involvement highlights a communication gap in oncology practice.

The numbers in context

350 patients surveyed (82% consent). 19% (67) using MC. Uses: pain 61%, cure cancer 12%, slow cancer 16%. Evidence perceived as high quality: users 28% (physical), 29% (anticancer); non-users 17%, 11%. Information from clinicians: users 31%, non-users 8%.

How the study worked

Survey of 413 Australian cancer patients attending oncology outpatient clinics (April 2019-March 2020). 82% consent rate (350 participants). Ages ≥18 with confirmed cancer diagnosis (solid or hematological).

What this study cannot tell us

Single center in Australia. Survey from 2019-2020 may not reflect current landscape. Self-reported cannabis use. Cannot assess actual evidence knowledge vs. perceived quality. Selection bias in clinic-attending patients.

How to read the evidence

Good response rate survey in a clinical setting, but single center, self-reported data, and pre-pandemic timing limit generalizability.

When this study was published

2025 publication with 2019-2020 survey data.

The bigger picture

Cancer patients are making decisions about medical cannabis largely without clinician input and based on non-medical sources. Even when patients recognize the evidence is weak, they still use cannabis, suggesting unmet symptom management needs that clinicians should address.

Questions still open

Would better clinician engagement about cannabis change patient behavior?
Are patients using cannabis because conventional symptom management is inadequate?

Common questions

Do cancer patients use medical cannabis?

In this Australian survey, 19% of cancer patients were using medical cannabis, primarily for pain (61%). Some used it hoping to cure (12%) or slow (16%) their cancer, though most recognized the evidence quality was limited.

Where do cancer patients get information about medical cannabis?

Mostly from non-clinical sources. Only 31% of cannabis users and 8% of non-users got information from clinicians. Most relied on TV, friends, family, social media, and websites, highlighting a major communication gap in oncology practice.

Read the original research

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

Asia-Pacific journal of clinical oncology, 21(5), 545-551

View on PubMed ↗Publisher’s paper ↗

Citation

Taylor, Joseph S; Fradgley, Elizabeth A; Britton, Ben Britton; Martin, Jennifer H; Lucas, Catherine; Carlson, Melissa A; Bridge, Paula; Morris, Sarah; Watts, Gareth; Lynam, James. (2025). Patients' Perceptions of the Efficacy, Safety, and Quality of the Evidence of Medicinal Cannabis: A Survey of Australian Cancer Patients.. Asia-Pacific journal of clinical oncology, 21(5), 545-551. https://doi.org/10.1111/ajco.14149