"The capacity to use image data during the delivery of radiation therapy represents a major development in radiation oncology, and along with adaptive radiotherapy, it is the topic of this review on Image Guided Adaptive Radiation Therapy (IGART). The book is edited by Robert Timmerman and Lei Xing, with 22 chapters by 71 authors grouped into three parts. Part I is an overview of image-guided adaptive radiotherapy (IGART), with two informative introductory chapters summarizing its rationale, methods, current status, and future expectations. It explains current image-guided radiotherapy (IGRT) and IGART methods, with the assistance of a table that allows comparisons among different methods. Next are several chapters, each explaining a major topic in IGART, such as errors and margins, management of respiratory motion, IGART in brachytherapy, stereotactic radiosurgery, and stereotactic body RT, and implanted fiducial markers. The justification for IGART is to ‘‘reduce the uncertainty and treatment margins,’’ by addressing three issues—tumor delineation, interfractional, and intrafractional uncertainties, and the chapter on errors and margins is particularly well-written, identifying the gain that is achieved and potentially achievable by addressing each of these three issues.The second part of the book is organized by anatomic site, with chapters focusing on IGART for head-and-neck, lung, breast, liver, gastrointestinal, genitourinary, gynecologic, central nervous system, and pediatric cancers. The type and amount of uncertainties, treatment margins, possible IGART applications, and potential clinical gain from IGART are explored for each treatment site...overall, they convey a thorough description of the role of IGART in each of these anatomic sites.Part III discusses the technical and practical challenges encountered when introducing IGART to the clinic. IGART applications, especially the frequent plan adaptations, require effective solutions to manage challenges such as increased workload, reimbursement for the additional work, increased complexity of operation and equipment, an increased possibility of error, and more difficult data management and access. A long chapter outlines seven commercially available IGART platforms, each in a separate subsection written by the developers of these technologies...learning the systems’ existing capabilities, as well as the vendors’ works in progress, is informative.""The book provides high-quality information and perspective, with coverage both wide and deep on topics of interest. Both the novice and experienced users of IGART can learn from this book, and the book should be a source of ideas for investigators."Ergun Ahunbay, Ph.D.Department of Radiation OncologyMedical College of WisconsinMilwaukee, WI
