This book provides a comprehensive and up-to-date overview of gastrointestinal stromal tumors (GISTs). GISTs represent the most common mesenchymal neoplasms arising within the gastrointestinal tract. The causative gene of this disease was originally discovered in Japan by Prof. Seichi Hirota in 1998, and since then numerous important advances from basic to clinical aspects have been reported from Japan. Professionals involved in the management of GISTs inevitably cite significant evidence and the state-of-the-art treatments from the Asian region, where has there is and inherently high prevalence of gastrointestinal cancers. Each expert author elucidates the cutting-edge knowledge on pathophysiology, diagnosis, and treatment of GISTs, especially focusing on the highly valuable data from Japan.