Cancer can occur in all parts of the body, body surface or internal organs, and only the hair area may not have this kind of malignant tumor. Cancer examination generally requires imaging, endoscopy or further pathological examination to fully confirm the diagnosis, and pathological examination is generally required to confirm the diagnosis. The examination methods are different for different parts of cancer, such as: 1) lung cancer, which is mainly detected by CT examination, and then further percutaneous lung aspiration biopsy or bronchoscopy can be performed to obtain a clear diagnosis of pathology; 2) stomach and intestinal cancer, generally speaking, according to clinical symptoms, such as abdominal pain and acid reflux, endoscopy and biopsy pathology are required to confirm the diagnosis. Imaging examination is not able to determine whether there are lesions in the stomach or intestinal tract.