You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Prepyloric or channel ulcer in the stomach is termed as the following type: and explain in detail?
Gastric ulcers have been classified based on their location: Type I occur in the gastric body and tend to be associated with low gastric acid production; Type II occur in the antrum and gastric acid can vary from low to normal; Type III occur within 3 cm of the pylorus and are commonly accompanied by duodenal ulcers and normal or high gastric acid production; Type IV are found in the cardia and are associated with low gastric acid production. Ref: Valle J.D. (2012). Chapter 293. Peptic Ulcer Disease and Related Disorders. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.