Gastrointestinal cancer is the most frequently diagnosed type of cancer worldwide. Gastrointestinal cancer is the cancer of different organs within the digestive system, including the esophagus, stomach, liver, gallbladder, pancreas, small intestine, large intestine, rectum and anus. The common cause of gastrointestinal cancer may be a microbial infection, smoking, alcohol consumption, highly fatty foods, age, race, genetic pattern and geographical location. Gastrointestinal cancer accounts more than 20 percent of all newly diagnosed cancer cases in the United States, where gastric cancer is the fourth-most-common type of cancer and the second-highest cause of cancer deaths. Pancreatic cancer is also a very lethal cancer, and its symptoms appear when the cancer is in its advanced stages. Other gastrointestinal cancers including liver (hepatic), gallbladder, and colorectal cancer; these types of cancer have received considerable attention due to their rising incidences in last few decades. Some other gastrointestinal cancers are not very common and usually associated with cancer of respective organs such as esophageal cancer, cholangiocarcinoma or bile duct cancer, carcinoid tumor, pancreatic islet cell cancer, and duodenal cancer. This book provides a summary of the past, present and future of gastrointestinal cancer history. In this book, numerous international experts of gastrointestinal cancer are discussed, where authors have provided a complete view of the most common and widely used diagnostic methods. Additionally, the authors also explain the unusual techniques and the most innovative complementary methods not yet used in clinical practice. Contributors have also described the latest findings and the various clinical manifestations related to gastrointestinal cancer prevention and treatment. It covers numerous discoveries and inventions in the field of gastrointestinal cancer detection and analysis.