Pan-tumor analysis to investigate the obesity paradox in immune checkpoint blockade
Background Obesity is a risk factor for developing cancer but is also associated with improved outcomes after treatment with immune checkpoint inhibitors (ICIs), a phenomenon called the obesity paradox. To interrogate mechanisms of divergent immune responses in obese and non-obese patients, we examined the relationship among obesity status, clinical responses, and immune profiles from a diverse, pan-tumor cohort of patients treated with ICI-based therapy. Methods From June 2021 to March 2023, we prospectively collected serial peripheral blood samples from patients with advanced or metastatic solid tumors who received ICI as standard of care at Johns Hopkins. Patients were stratified by obesity status at treatment initiation, with obesity defined as body mass index (BMI)≥30 at treatment initiation and BMI≥18.5 and <30 considered non-obese; underweight patients (BMI<18.5) were excluded. We evaluated the concentration of 37 cytokines and used cytometry by time of flight to characterize im
