Promoting Immunotherapy Efficacy With Low-Dose Liver RT

This study is testing whether adding a low dose of targeted radiation to liver metastases (cancer that has spread to the liver) can boost the effectiveness of immunotherapy drugs (checkpoint inhibitors) in people with advanced non-small cell lung cancer or melanoma. The idea is that liver radiation may help "unlock" the immune response in patients whose tumors aren't responding well to immunotherapy alone. **You may be eligible if...** - You are 18 years or older - You have been diagnosed with non-small cell lung cancer (NSCLC) or melanoma that has spread to the liver - You are already planning to receive PD-1 or PD-L1 immunotherapy as part of your standard cancer care - You are in reasonably good health (ECOG score 2 or less, or Karnofsky 60% or above) - Your organ function and blood counts are adequate for both immunotherapy and radiation **You may NOT be eligible if...** - You do not have confirmed liver metastases - You are not eligible to receive checkpoint immunotherapy per your treating oncologist - You are pregnant or planning to become pregnant during the study - Your performance status is too poor for the planned treatments Talk to your doctor to see if this trial is right for you.