Impact of influenza syndrome and flu vaccine on survival of cancer patients during immunotherapy in the INVIDIa study.

INVIDIa was a retrospective, multicenter study, exploring the clinical efficacy of influenza vaccine in 300 cancer patients undergoing immunotherapy. Overall survival (OS) was immature at the initial report. We reported the final OS analysis from the original study population and within subgroups. Both at the univariate and multivariate analysis, the occurrence of influenza syndrome (IS) was significantly related to better OS in the overall population (OR: 0.53 [95% CI: 0.32-0.88]; p = 0.01). In the lung cancer subgroup, receiving flu vaccine and/or developing IS was related to better OS (p = 0.04). Within elderly patients, the flu vaccine was the main variable for the relative OS advantage (p = 0.05). Receiving the flu vaccine and/or developing IS was related to better OS within the INVIDIa population.