Cancer Nutrition Study - A Study of Dietary Interventions in Cancer Patients Treated With Immune Checkpoint Inhibitors

OBJECTIVES:Primary:1. To longitudinally assess changes in gut microbiota composition, diversity, andmetabolomic function in patients with solid tumors who develop grade ≥2 irAEs during ICItherapy and undergo dietary modification with either high‐fermented foods (Arm 1) orhigh‐fiber supplementation (Arm 2).Secondary: 1. To determine the safety and tolerability of dietary interventions in patients withICI‐related irAEs 2. To assess the incidence and severity of recurrent or new irAEs during and afterdietary intervention 3. To characterize changes in circulating innate and adaptive immune cell populations(frequency, phenotype, and function) associated with dietary modification 4. To measure changes in circulating inflammatory cytokines and metabolites associatedwith dietary interventionExploratory: 1. To assess patient‐reported gastrointestinal symptoms and quality of life duringdietary intervention 2. To determine adherence rates to assigned dietary interventions using dietary logsand biomarker validation 3. To explore associations between baseline physical activity levels and gut microbiomecomposition 4. To longitudinally assess skin and oral microbiota composition, diversity, andfunction in relation to dietary modification 5. To perform integrative multi‐omic analyses exploring relationships between diet,microbiome, immune phenotypes, and clinical outcomes