Molecular Assessment for Gastro-Esophageal Cancer

This study tests whether breath and blood samples can be used to detect stomach and esophageal cancer at an early stage or to identify pre-cancerous conditions like Barrett's esophagus. Researchers will analyze molecules in exhaled breath and blood for patterns linked to cancer. **You may be eligible if...** - You are over 18 years old - You have been diagnosed with Barrett's esophagus or gastro-esophageal cancer (any stage, untreated) - OR you are a healthy volunteer willing to donate a breath or blood sample for comparison **You may NOT be eligible if...** - You have another active cancer - You had a prior cancer treated less than 3 years ago - You have significant liver failure - You are incarcerated Talk to your doctor to see if this trial is right for you.