Novel Optical Surface Image Guidance System for Beam-Gated Online Adaptive SBRT Delivery in Mobile Lower Lung and Upper Abdominal Malignancies

Inclusion Criteria: * Primary or metastatic disease of the abdomen or lower thorax, with biopsy-proven or radiographically diagnosed disease histology of solid tumor categorization, with the exception of small cell cancers. * Must be medically fit for SBRT as determined by the treating physician, with at least one disease site to be deemed suitable for treatment with CT-guided stereotactic radiation to the abdomen or thorax as per radiation oncologist evaluation. * At least 18 years of age. * Karnofsky performance status \> 60 * Capable of single deep inspiratory breath-hold or end-exhale breath-hold of at least 17 seconds in duration and of repeated end-exhale or deep inspiratory breath-hold of at least 10 seconds in duration upon verbal instruction. * Must have completed any systemic therapy at least one week prior to planned start of SBRT (two weeks preferred), and must have no plans to initiate systemic therapy for at least one week following end of SBRT (two weeks preferred). * Able to understand and willing to sign an IRB approved written informed consent document (or that of legally authorized representative, if applicable). Exclusion Criteria: * Past history of radiotherapy within the projected treatment field of any of the disease sites to be treated by CT-guided SBRT. * Currently receiving any investigational agents. * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements. * Pregnant and/or breastfeeding. Patient must have a negative pregnancy test within 14 days of study entry.