Existential interventions in cancer : an umbrella review

Conclusions about the effectiveness of existential interventions for cancer patients are limited by the application of various intervention types and outcomes. We conducted an umbrella review to create a comprehensive overview of their effectiveness, to guide clinical decision-making and future research. We aimed to a) identify which outcomes can be effectively influenced by existential interventions, and b) determine factors impacting treatment outcomes. We systematically searched four databases. Main selection criteria were: 1) systematic review of quantitative studies or meta-analysis, 2) reviewing the effectiveness of existential interventions, and 3) including adult cancer patients. The search yielded 855 unique records. Eight reviews were included in the final analysis. Existential interventions had a beneficial (short-term) impact on meaning, hope, quality of life, self-efficacy, and self-esteem. Effects on psychopathology and physical distress were inconsistent and non-significant, respectively. Treatment effects were not influenced by patient characteristics, while intervention provider and intensity as well as study quality played a role. Concluding, existential interventions appear to improve the existential and psychological well-being of adult cancer patients. Potentially, effects on existential outcomes are intervention-specific and only subsequently alleviate psychopathology. Future research could investigate the culture-specificity and adverse effects of existential interventions.