4D-CT-based Ventilation Imaging for Adaptive Functional Guidance in Radiotherapy

Inclusion Criteria: * Eligible disease(s)/stage(s) AJCC Stage I, II, III or IV lung cancer of any histology to be treated using radiotherapy will be eligible for this study. Note that we will carefully consider the inclusion of cases with turbulent flow or greater flow velocities (Cabahug et al., 1996; Crawford et al., 1990) and COPD cases (Magnant et al., 2006) due to the impaction of aerosol particles in central airways. * Allowable type and amount of prior therapy. Any types and amounts of prior therapy will be allowed for this study. * Age restriction and/or gender/ethnic restrictions * Patients must be greater than or equal to 18 years of age. * There are no gender or ethnic restrictions. * Life expectancy restrictions - None. * ECOG or Karnofsky Performance Status * Not employed. Note that patients will need to be sufficiently healthy to undergo audiovisual (AV) biofeedback to generate high quality 4D-CT images. * Requirements for organ and marrow function None. * Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: Children (less than 18 years of age), pregnant women, Stanford employees or students, or prisoners will be excluded from this study.