Less effective diagnostic markers for ESCA can be used in present. Nitrogen elements include a variety of nitrogen isotopes with various mass. Stable nitrogen isotope ratios 15 Nitrogen/14 Nitrogen (15 N/14 N) are of particular advantage to understand the metabolic state of cancer cells, since most biochemical reactions involve transfer of nitrogen. Cancerous cells can recycle metabolic ammonium for their growth . The recycling of this ammonium with a low nitrogen isotope ratio (15 N/14 N) may cause cancer tissue to have lower 15 N/14 N than surrounding healthy tissue, and it could diagnose malignancy as well as an avenue for investigation of cancer metabolism.~However, the relationship and diagnostic value between nitrogen excretion from oral gas and ESCA remains unclear. The purpose of this study is to analyze the diagnostic value of various mass nitrogen isotope excreting for oral gas for ESCA.
The purpose of this study is to determine the diagnostic value of various nitrogen isotopes(N) in oral gas for esophagus cancer (ESCA) .