Surgery, chemotherapy, and radiation are the major treatments for stomach cancer. You might get one or a combination of these treatments.   You could need chemotherapy before surgery if it's suggested. If the tumor is in the upper region of your stomach, including the oesophagus-stomach junction, you may need radiation before surgery. Chemotherapy and radiation are usually used after surgery.   The primary goal of treatment is to eradicate the tumor and any other cancerous cells in your body as completely as possible. A cure is believed to be achievable in 20 to 30 percent of stomach cancer patients.