Consolidative Use of Radiotherapy to Block (CURB2) Oligoprogression In Patients With Metastatic Non-Small-Cell Lung Cancer

This study is being done to answer the following question: Can the chance of lung cancer growing or spreading be lowered by adding targeted radiotherapy to the usual combination of drugs>= This study is being done to find out if this approach is better or worse than the usual approach for lung cancer. The usual approach is defined as the care most people get for non-small cell lung cancer.

Other: First or second-line standard of care therapy