Local Consolidative Therapy and Durvalumab for Oligoprogressive and Polyprogressive Stage III NSCLC After Chemoradiation and Anti-PD-L1 Therapy

This trial is studying whether adding more targeted radiation therapy (to the sites of cancer progression) plus continued immunotherapy with durvalumab can help patients with stage III non-small cell lung cancer (NSCLC) whose disease has progressed or persisted after completing standard chemoradiation plus durvalumab treatment. **You may be eligible if...** - You are 18 or older with stage III NSCLC - You received standard chemoradiation followed by durvalumab and your disease either progressed or persisted (shown on PET scan 6+ months after treatment, confirmed by biopsy) - Your disease has 3 or fewer new sites of progression (Cohort A) or more than 3 sites (Cohort B) - You have good performance status (ECOG 0–1) and adequate organ function - You are able to receive radiation therapy to at least one site **You may NOT be eligible if...** - Your disease rapidly progressed within the first 3 months of starting durvalumab after chemoradiation - You received a different immunotherapy drug than durvalumab - Your lung adenocarcinoma has mutations (EGFR, ALK, ROS1, RET, MET) with standard targeted therapy options - You have unresolved significant side effects from prior cancer treatment - You have active autoimmune disease Talk to your doctor to see if this trial is right for you.