Presentations at ESMO and institutional studies from MD Anderson and the University of Florida reported that patients who received mRNA Covid‑19 vaccines within a defined window before starting immune checkpoint inhibitors lived longer than comparable unvaccinated patients. Investigators proposed vaccine‑induced immune priming as a potential mechanism. The MD Anderson retrospective analysis and supporting UF observations examined timing and outcomes in advanced cancer cohorts treated with PD‑1 blockade; both groups reported improved survival metrics associated with recent mRNA vaccination. Authors called for controlled trials to validate causality and define optimal timing. If confirmed prospectively, the interaction could affect vaccination timing guidelines for oncology patients, trial stratification practices, and immunotherapy scheduling policies across centers.