Sex and Dendritic Cell Vaccination Performance in Cancer – So What Difference Does It Make? A Review and Meta-Analysis

Numerous clinical trials of dendritic cell (DC)‑based vaccines have been conducted across various cancers. However, sex‑related differences in clinical benefit from DC‑based vaccination remain under‑investigated. To assess association between patient sex and efficacy of DC‑based cancer vaccines - specifically overall and progression‑free survival - we conducted comprehensive searches of PubMed and ClinicalTrials.gov to identify relevant clinical trial studies published up to January 2025. Of 869 potentially relevant studies, 59 met inclusion criteria and were included in the meta‑analysis. Pooled analyses revealed a statistically significant association between sex and DC vaccine efficacy: females demonstrated greater clinical benefit than males, with a 24% lower Hazard Ratio for Overall Survival (Hazard Ratio 0.76;95% Confidence Interval 0.65–0.90;P=0.0008) and a 24% lower Hazard Ratio for Progression‑Free Survival (Hazard Ratio 0.76;95% Confidence Interval 0.61–0.94;P=0.01). Although no statistically significant heterogeneity was detected and overall bias risk was low, the findings should be interpreted in the context of substantial variability in DC vaccine platforms, trial designs, and the limited availability of phase III data. Within this context, our meta‑analysis identifies an association between patient sex and clinical outcomes following DC‑based cancer vaccination. Specifically, female patients tended to experience improved overall and progression‑free survival compared with male patients. While these results do not establish causality, they suggest that sex may be a relevant biological factor influencing response to DC‑based immunotherapy. These observations support the inclusion and prospective evaluation of sex as a biological variable in the design, reporting, and analysis of future cancer immunotherapy trials.