When something is wrong with your stomach, life can be miserable. More likely than not, stomach upset and other symptoms are due to a noncancerous condition. But sometimes, stomach cancer is the cause. Stomach cancer—or gastric cancer—is not a very common cancer. In the United States, there are about 26,000 new cases each year. This ranks it 14th among the major types of cancer in this country. Early Stomach Cancer Symptoms Stomach cancer can take years to develop. In the early stages, it is rare to have symptoms. The tumor can grow without causing much noticeable discomfort. Once symptoms become bothersome, they are usually vague and do not raise a red flag specific for cancer. Because of this, only about 10 to 20% of stomach cancers are diagnosed in early stages when it remains in the stomach. Early stomach cancer symptoms can include: Appetite loss or feeling full after eating small amounts Bloating or vague discomfort Heartburn, indigestion, or stomach upset Mild nausea These symptoms can also be present with other more common stomach conditions. Examples include a viral infection, GERD (gastroesophageal reflux disease), or stomach ulcer. The similarity with other conditions and vagueness of these symptoms contributes to the difficulty in diagnosing stomach cancer early. Symptoms and Signs of Advanced Stomach Cancer Stomach cancer is usually in advanced stages at diagnosis. This means the cancer has either spread to nearby tissues or to distant body sites. At these later stages, symptoms become more obvious. Symptoms and signs of stomach cancer in later stages can include: Ascites, which is a buildup of fluid in the abdomen causing swelling and distention Jaundice, which is yellowing of the eyes or skin Stomach pain or trouble swallowing Unexplained weight loss Vomiting, which may be bloody, or having blood in the stool, both of which can cause anemia (low red blood cell counts) Weakness and fatigue Diagnosing Stomach Cancer You will likely see a gastroenterologist if your doctor suspects stomach cancer. Gastroenterologists specialize in diagnosing and treating digestive conditions. So this doctor is an expert at figuring out the cause of stomach problems. After taking a medical history and doing a physical exam, your doctor may order blood tests. This can include blood chemistry tests and a complete blood count (CBC). If something is off with these tests, it may indicate some sort of disease is present. But these tests alone can’t diagnose stomach cancer. Your doctor will also need to order tests to look inside your stomach. Upper GI endoscopy lets your doctor examine the stomach lining. You will have sedation during an upper endoscopy. This is the main test for determining whether cancer is causing your symptoms. It involves passing an endoscope down your throat into your stomach. The endoscope has a lighted camera so your doctor can look for abnormal areas. If an abnormality is present, your doctor can use the endoscope to take a tissue sample (biopsy). A biopsy is the only way to know for sure whether it is cancer or not. A lab will test the tissue sample to see if cancer cells are present. If it is stomach cancer, the lab can run some additional tests to tell your doctor about the cancer. This includes the specific type of stomach cancer and whether it has certain characteristics, such as over-expressing the HER2 protein. Your doctor may also order additional imaging exams during the diagnostic process. These exams can include: CT (computed tomography) MRI (magnetic resonance imaging) PET (positron emission tomography) Upper GI series, which is an X-ray exam using barium for contrast The results can help your doctor find out if the cancer has spread and how far. Your doctor will use these results, along with your biopsy results, to plan the most effective treatment for you.