Nutritional status and survival outcomes in patients with cancer treated with immune checkpoint inhibitors: The ARON-MOUSEION-20 systematic review and meta-analysis

Introduction The prevalence of malnutrition in cancer patients is already high at diagnosis, reaching up to 40%, and tends to increase during treatment, affecting up to 75-80% of patients. To investigate the relationship between nutritional status and clinical outcomes, Progression-Free Survival (PFS) and Overall Survival (OS), in patients treated with Immune Checkpoint Inhibitors (ICIs).Methods The present systematic review and meta-analysis was registered in PROSPERO with id no. CRD420261356035. Embase, PubMed, Scopus and Web of Science databases were consulted by combining Boolean terms and keywords, specifically: "immune checkpoint inhibitors", "neoplasms", "nutrition assessment", "'overall survival" and "progression-free survival".Results We pooled data from 19 studies reporting multivariable-adjusted hazard ratios (HR) for the association between Prognostic Nutritional Index (PNI) and PFS. The pooled analysis did not demonstrate a statistically significant association between PNI and PFS (HR = 0.85; 95% CI = [0.59; 1.23]; Z = -0.87; P = 0.385). The pooled estimate indicated no statistically significant effect of PNI on overall survival (OS), (HR = 1.23; 95% CI = [0.82; 1.84]; Z = 0.997; P = 0.319). While not statistically significant, the point estimate suggested a trend toward slightly poorer survival in patients with higher PNI values. For the association between PNI assessed by CONUT and PFS, the pooled analysis did not demonstrate a statistically significant association between PNI and PFS (HR = 1.01; 95% CI = [0.69; 1.48]; Z = 0.03; P = 0.972), and no clear trend toward improved or worse PFS was observed among patients with higher PNI values.Conclusion Despite the increasing attention to the role of nutrition in oncology, the available literature still included relatively few studies that comprehensively assessed nutritional status during the pre-treatment, treatment, and post-treatment phases. Longitudinal investigations describing changes in nutritional status throughout the therapeutic pathway remained poor. Adequate nutritional support could contribute to improving patients' overall health status, optimizing treatment tolerability, and potentially enhancing clinical outcomes associated with anticancer therapies.