Influence of Radiotherapy and Chemotherapy in the Value of Peripheral Blood Lymphocyte Subsets Among Thoracic Cancer

This study is tracking how radiation and chemotherapy affect the immune cells in the blood of patients with thoracic (chest) cancers, including lung cancer and esophageal cancer, to better understand how these treatments influence the immune system. **You may be eligible if...** - You are at least 18 years old - You have been diagnosed with non-small cell lung cancer, esophageal squamous cell carcinoma, or a thymic tumor, confirmed by biopsy - You are in good physical condition (ECOG PS 0-1) - Your life expectancy is more than 3 months - You are receiving radiation therapy as part of your treatment **You may NOT be eligible if...** - You are receiving palliative (comfort-focused) radiation only - You have serious active infections or autoimmune disorders - You have significant organ dysfunction Talk to your doctor to see if this trial is right for you.