The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital digestive organ. In the digestive system the stomach is involved in the second phase of digestion, following chewing. It performs a chemical breakdown due to enzymes and hydrochloric acid.Encyclopedia Entry for Stomach :Stomach acid test. The test is done after you have not eaten for a while so fluid is all that remains in the stomach. Stomach fluid is removed through a tube that is inserted into the stomach through the esophagus (food pipe). A hormone called gastrin may be injected into your body. This is done to test the ability of the cells in the stomach to release acid. The stomach contents are then removed and analyzed.You will be asked not to eat or drink for 4 to 6 hours before the test.You may have some discomfort or a gagging feeling as the tube is inserted.Your health care provider may recommend this test for the following reasons: To check if anti-ulcer medicines are working To check if material is coming back up from the small intestine To test for the cause of ulcers.The normal volume of the stomach fluid is 20 to 100 mL and the pH is acidic (1.5 to 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour (mEq/hr) in some cases. Note: Normal value ranges may vary slightly depending on the lab doing the test. Talk to your provider about the meaning of your specific test results.Abnormal results may indicate: Increased levels of gastrin can cause increased release of acid and may lead to ulcers ( Zollinger-Ellison syndrome ). The presence of bile in the stomach indicates material is backing up from the small intestine ( duodenum ). This may be normal. It may also happen after part of the stomach is removed with surgery.There is a slight risk of the tube being placed through the windpipe and into the lungs instead of through the esophagus and into the stomach.Gastric acid secretion test.Stomach acid test Stomach acid test.Chernecky CC, Berger BJ. Gastric acid secretion test (gastric acid stimulation test).Encyclopedia Entry for Stomach :Stomach cancer. Several types of cancer can occur in the stomach. The most common type is called adenocarcinoma. It starts from one of the cell types found in the lining of the stomach. Adenocarcinoma is a common cancer of the digestive tract. It is not very common in the United States. It is diagnosed much more often in people in eastern Asia, parts of South America, and eastern and central Europe. It occurs most often in men over age 40. The number of people in the United States who develop this cancer has decreased over the years. Experts think this decrease may be in part because people are eating less salted, cured, and smoked foods. You are more likely to be diagnosed with gastric cancer if you: Have a diet low in fruits and vegetables Have a family history of gastric cancer Have an infection of the stomach by a bacteria called Helicobacter pylori Had a polyp (abnormal growth) larger than 2 centimeters in your stomach Have inflammation and swelling of the stomach for a long time (chronic atrophic gastritis ) Have pernicious anemia (low number of red blood cells from intestines not properly absorbing vitamin B12) Smoke.Symptoms of stomach cancer may include any of the following: Abdominal fullness or pain, which may occur after a small meal Dark stools Difficulty swallowing, which becomes worse over time Excessive belching General decline in health Loss of appetite Nausea Vomiting blood Weakness or fatigue Weight loss.Diagnosis is often delayed because symptoms may not occur in the early stages of the disease. And many of the symptoms do not specifically point to stomach cancer. So, people often self-treat symptoms that gastric cancer has in common with other, less serious, disorders (bloating, gas, heartburn, and fullness). Tests that can help diagnose gastric cancer include: Complete blood count (CBC) to check for anemia. Esophagogastroduodenoscopy (EGD) with biopsy to examine the stomach tissue. EGD involves putting a tiny camera down the esophagus (food tube) to look at the inside of the stomach. Stool test to check for blood in the stools.Surgery to remove the stomach ( gastrectomy ) is the standard treatment that can cure adenocarcinoma of the stomach. Radiation therapy and chemotherapy may help. Chemotherapy and radiation therapy after surgery may improve the chance of a cure. For people who cannot have surgery, chemotherapy or radiation may improve symptoms and may prolong survival, but may not cure the cancer. For some people, a surgical bypass procedure may relieve symptoms.You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.Outlook varies based on how much the cancer has spread by the time of diagnosis. Tumors in the lower stomach are cured more often than those in the higher stomach. Chance of a cure also depends on how far the tumor has invaded the stomach wall and whether lymph nodes are involved. When the tumor has spread outside the stomach, a cure is less likely. When a cure is not possible, the goal of treatment is to improve symptoms and prolong life.Call your health care provider if symptoms of gastric cancer develop.Screening programs are successful in detecting disease in the early stages in parts of the world where the risk of stomach cancer is much higher than in the United States. The value of screening in the United States and other countries with much lower rates of stomach cancer is not clear. The following may help reduce your risk of stomach cancer: DO NOT smoke. Keep a healthy diet rich in fruits and vegetables. Take medicines to treat reflux disease (heartburn) , if you have it. Take antibiotics if you are diagnosed with H pylori infection.Cancer - stomach; Gastric cancer; Gastric carcinoma; Adenocarcinoma of the stomach.Digestive system Digestive system Stomach cancer, X-ray Stomach cancer, x-ray Stomach Stomach Gastrectomy - series Gastrectomy - series.Abrams JA, Quante M. Adenocarcinoma of the stomach and other gastric tumors.