New imaging technique aims to reduce lung damage during cancer radiation

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age 18 to 85 years (inclusive); any sex. * Diagnosed lung malignancy requiring thoracic radiotherapy (e.g., non-small cell lung cancer, small cell lung cancer, or pulmonary metastases). * Planned to receive thoracic radiotherapy using either conventionally fractionated IMRT/VMAT or stereotactic body radiotherapy (SBRT), and able to complete pre-treatment 4DCT simulation suitable for generating a ventilation map. * Adequate baseline organ function and clinically judged able to tolerate radiotherapy; ECOG performance status 0-1. * No absolute contraindication to pulmonary function testing; patients with moderate COPD or impaired lung function may be included if the treating team judges radiotherapy to be tolerable. * Able to comply with treatment and follow-up assessments. * Written informed consent provided. Exclusion Criteria: * Pregnant or breastfeeding women. Women of childbearing potential must have pregnancy excluded prior to radiotherapy per institutional practice. * Age \<18 or \>85 years. * Uncontrolled severe cardiopulmonary disease or other severe comorbidities that make radiotherapy excessively high risk (e.g., decompensated heart failure, unstable cardiopulmonary status, active severe pulmonary infection). * Prior high-dose thoracic radiotherapy to the same region such that safe re-irradiation is not feasible. * Concurrent other active/advanced malignancy requiring priority treatment that would confound study outcomes. * Recent participation in another interventional clinical trial or concurrent investigational therapy judged likely to interfere with this study's endpoints. * Severe psychiatric, cognitive, or other conditions that prevent cooperation with radiotherapy and/or scheduled follow-up. * Inadequate 4DCT image quality or inability to generate/validate the 4DCT ventilation map required for functional-lung-guided planning. * Any other condition deemed unsuitable by the investigators in the interest of participant safety.