Longitudinal Evaluation of Microbial and Host Signatures During Immunotherapy for Lung Cancer

This study will prospectively collect airway, stool, and blood samples on 80 subjects with lung cancer undergoing immunotherapy. Investigators will evaluate airway/stool microbial signatures associated with local (lower airway) and systemic (blood) immune tone.They will then study whether microbiota and/or host signatures predict subjects' response by longitudinal assessment of the progression free survival. They will also repeat sampling after 8 weeks of immunotherapy to expand our mechanistic understanding of the response to treatment.