Psychedelic-Assisted Therapies for Psychosocial Symptoms in Cancer: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis examined whether psychedelic-assisted therapies, especially psilocybin and ketamine, can reduce psychological distress like anxiety, depression, and existential suffering in adults with cancer. Eleven randomized controlled trials and four open-label studies were included. Meta-analyses showed that ketamine led to rapid, large reductions in depression and anxiety shortly after treatment, while psilocybin also showed large potential benefits but with higher variability across studies. Trials using psilocybin included structured psychotherapy, whereas ketamine was given without therapy. Early evidence from small studies of other psychedelic agents suggests possible benefits for distress in cancer patients, but more rigorous research is needed. Overall, while psychedelic-assisted therapies appear promising and well-tolerated, evidence certainty remains low due to small sample sizes, methodological differences, and limited long-term data. Larger, well-designed trials focused specifically on cancer populations are needed to clarify how best to integrate these treatments into oncology care.