If the endoscopy shows a lesion, or an ulcer or growth, then, a biopsy is done. Sometimes, if the patient is bleeding inside, then, his stool might show blood. So, he may present with black stool. Then, a stool routine test may show the presence of occult blood. One of the reasons for having such occult blood is gastric cancer.
Gastric cancer spreads very fast.
The younger is the patient the furious is the cancer. To treat gastric cancer, surgery is the only option. Radiation therapy and chemotherapy are hardly affective. Adenocarcinomas, generally, are non responsive to radiation and chemotherapy. Once gastric cancer is diagnosed, then, the physician will look out whether it is operable by doing a CT scan.