Psychedelic-Assisted Therapies for Psychosocial Symptoms in Cancer: A Systematic Review and Meta-Analysis
Current Oncology – June 30, 2025
Source: OpenAlex
Summary
Psychedelics offer significant promise for cancer patients. A meta-analysis of randomized controlled trials, including data from the Cochrane Library, revealed that psilocybin and ketamine markedly reduce psychosocial distress. For instance, three psilocybin trials with 101 participants showed a large effect on depression (Hedges' g = -3.13). Four ketamine trials (354 participants) demonstrated rapid, large effects on depression and anxiety (Hedges' g = -1.37) compared to placebo. This burgeoning area of medicine, relevant to psychiatry and clinical psychology, highlights how these chemical synthesis alkaloids influence behavior, offering new therapeutic context for internal medicine.
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.