Psychedelic-Assisted Therapies for Psychosocial Symptoms in Cancer: A Systematic Review and Meta-Analysis
Haley D M Schuman, Chantal Savard, Raèf Mina, Sofia Barkova, Hanna S W Conradi, Julie M Deleemans, Linda E Carlson
Current Oncology June 30, 2025 DOI: 10.3390/curroncol32070380 via OpenAlex
Summary
AI-generated from the abstractA systematic review and meta-analysis of 11 placebo-controlled randomized trials and 4 open-label studies found that psychedelic-assisted therapy with psilocybin or ketamine can reduce depression and anxiety in adults with cancer. Meta-analysis of four ketamine trials (354 participants) showed a large, rapid effect on depression and anxiety. Three psilocybin trials (101 participants) also showed a large effect on depression, though with wide variability. Non-randomized studies of MDMA and LSD suggested promise but were less rigorous. The authors conclude that psychedelic-assisted therapy may offer meaningful relief for cancer-related distress, but effects vary by therapeutic model and context, and more oncology-specific trials are needed.
Study at a glance
| Characteristics | Systematic review and meta-analysis Randomized Placebo-controlled Open-label Peer reviewed |
|---|---|
| Sample size | 455 |
| Population | Adults with cancer |
| Interventions | Psilocybin Ketamine |
| Topics | Anxiety Depression Ketamine Psilocybin Psychedelic-assisted therapy |
| Citations | 9 |
| Key finding | Psychedelic-assisted therapy with psilocybin or ketamine may reduce depression and anxiety in adults with cancer, with meta-analyses showing large effects, though variability and limited evidence from non-randomized studies highlight the need for further trials. |
Abstract
This systematic review and meta-analysis evaluates (1) the effectiveness of psychedelic-assisted therapy (PAT) using psilocybin and ketamine for psychosocial symptoms in adults with cancer, (2) contextualizes findings with non-randomized and exploratory studies of other psychedelics, and (3) examines the role of therapeutic frameworks in shaping outcomes. We searched PubMed, Cochrane Library, PsycINFO, and EMBASE (2000–2024) for randomized controlled trials (RCTs) and non-randomized studies investigating psychedelic agents in cancer populations. Meta-analyses pooled RCTs of psilocybin or ketamine using random-effects models. Non-randomized studies were synthesized narratively. Risk of bias and evidence certainty were assessed via Cochrane ROB 2.0, NIH Before–After tool, and GRADE. Eleven placebo-controlled RCTs and four single open-label studies were included. Meta-analysis of four ketamine RCTs (n = 354) showed large, rapid effects on depression/anxiety (Hedges’ g = −1.37, 95% CI: −2.66 to −0.08; I2 = 92%). Three psilocybin RCTs (n = 101) showed a large effect of psilocybin on alleviating depression (Hedges’ g = −3.13, 95% CI: −10.04 to 3.77; I2 = 95%). MDMA and LSD trials suggested promise but lacked rigor. PAT may offer meaningful relief for cancer-related distress, though effects vary by therapeutic model and context. Oncology-specific trials are needed to standardize and scale for implementation.