No high-quality evidence supports cannabis for anxiety, depression, or insomnia in cancer patients | Research

The takeaway

A MASCC systematic review of 15 randomized trials found no high-quality evidence to recommend cannabis for psychological symptoms in cancer patients, though 6 of 15 trials suggested some benefit for sleep.

Oncologists, palliative care specialists, cancer supportive care providers

0 RCTs assessed psychological symptoms as primary outcomes in cancer patients using cannabis

What the researchers found

From 829 articles screened, 2 systematic reviews and 15 RCTs met criteria. No studies assessed cannabis efficacy on psychological symptoms as primary outcomes in cancer. Studies varied widely in interventions, controls, duration, and outcomes. Six of 15 RCTs suggested benefits: five for sleep and one for mood. The evidence was insufficient to recommend cannabis for anxiety, depression, or insomnia in cancer patients.

Why it matters

With 18% of cancer patients already using cannabis for symptom management, this guideline from a major supportive care organization provides important clarity: the evidence does not yet support this practice for psychological symptoms.

The numbers in context

829 articles screened; 15 RCTs and 2 systematic reviews included; 4 studies on sleep, 5 on mood, 6 on both; 6/15 suggested benefits (5 for sleep, 1 for mood)

How the study worked

Systematic review searching MEDLINE, CCTR, EMBASE, and PsychINFO up to November 2021. Inclusion criteria: randomized controlled trials and systematic reviews of cannabis versus placebo or active comparator in cancer patients with psychological symptom outcomes.

What this study cannot tell us

No RCTs had psychological symptoms as primary outcomes, making all evidence secondary. Studies were heterogeneous in cannabis type, dose, and measurement tools. Search limited to November 2021.

How to read the evidence

Rigorous systematic review from a major cancer supportive care organization, but limited by the poor quality and heterogeneity of available trials.

When this study was published

Published 2023

The bigger picture

Cancer patients using cannabis for anxiety and depression are doing so in an evidence vacuum. Until high-quality trials with psychological symptoms as primary outcomes are conducted, clinical decisions rely on extrapolation from inadequate data.

Questions still open

Would RCTs specifically designed to assess cannabis for cancer-related insomnia confirm the promising signals from secondary analyses? Why has no trial prioritized psychological outcomes despite widespread patient use?

Common questions

Does cannabis help with anxiety or depression in cancer patients?

Current evidence is insufficient. A systematic review of 15 randomized trials found no study specifically designed to test this, and only 1 of 15 trials suggested mood benefits. The MASCC guidelines cannot recommend cannabis for these symptoms.

Can cannabis help cancer patients sleep?

There are some promising signals. Five of 15 randomized trials suggested sleep benefits, but study designs varied widely and none had insomnia as a primary outcome.

Read the original research

Multinational Association of Supportive Care in Cancer (MASCC) guidelines: cannabis for psychological symptoms including insomnia, anxiety, and depression.

Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer, 31(3), 176

View on PubMed ↗Publisher’s paper ↗

Citation

De Feo, Giulia; Case, Amy A; Crawford, Gregory B; Hui, David; To, Josephine; Sbrana, Andrea; Alderman, Bryony; Mukhopadhyay, Sandip; Bouleuc, Carole; Amano, Koji; Tanco, Kimberson; Garsed, Jessica; Davis, Mellar. (2023). Multinational Association of Supportive Care in Cancer (MASCC) guidelines: cannabis for psychological symptoms including insomnia, anxiety, and depression.. Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer, 31(3), 176. https://doi.org/10.1007/s00520-023-07628-3