The impact of ECOG performance status on efficacy of immunotherapy and immune-based combinations in cancer patients: the MOUSEION-06 study

: ECOG performance status (PS) is a pivotal prognostic factor in a wide number of solid tumors. We performed a meta-analysis to assess the role of ECOG PS in terms of survival in patients with ECOG PS 0 or ECOG PS 1 treated with immunotherapy alone or combined with other anticancer treatments. Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses, all phase II and III randomized clinical trials that compared immunotherapy or immune-based combinations in patients with solid tumors were retrieved. The outcomes of interest were overall survival (OS) and progression-free survival (PFS). We also performed subgroup analyses focused on type of therapy (ICI monotherapy or combinations), primary tumor type, setting (first line of treatment, subsequent lines). Overall, 60 studies were included in the analysis for a total of 35.020 patients. The pooled results showed that immunotherapy, either alone or in combination, reduces the risk of death or progression in both ECOG PS 0 and 1 populations. The survival benefit was consistent in all subgroups. Immune checkpoint inhibitors monotherapy or immune-based combinations are associated with improved survival irrespective of ECOG PS 0 or 1. Clinical trials should include more frail patients to assess the value of immunotherapy in these patients.