Gastrointestinal cancer is the most frequently diagnosed type of cancer all around the globe. Gastrointestinal cancer is the cancer of different organs of 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 microbial infection, smoking, alcohol consumption, high fat food, age, race, genetic pattern and geographical location. Gastrointestinal cancer accounts more than 20 percent of all newly diagnosed cancer cases in 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 advanced stage. Other gastrointestinal cancers including Liver (hepatic), gallbladder, and colorectal cancer have received considerable attention due to the rising incidence 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 various gastrointestinal cancer history, present and future. In this book, numerous international experts of gastrointestinal cancer have involved, where authors have provided a complete view of the most common and widely used diagnostic methods, and also explaining 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.