In many instances, cancer can expertly conceal itself, but not its chemical compositions. Exploiting the chemical signatures of cancer is a growing field of cancer diagnostics. Now, researchers at the Imperial College London have developed a breathalyzer that picks up chemical traces for the detection of stomach and esophageal cancer.
https://www.labroots.com/trending/cancer/5236/breathalyzer-stomach-esophageal-cancer
A Breathalyzer for Stomach and Esophageal Cancer