The field of Adolescent and Young Adult (AYA) oncology is experiencing a very challenging time. This book is a guide to the key issues for any clinician managing AYA with cancer in Europe. Emphasis is on collaboration between adult and pediatric specialists. Authors present their perception of the current state of the most prominent primary issues in AYA oncology. Chapters cover cross-cutting issues such as disease epidemiology, systems of care, and late effects of treatment and survivorship for AYA-onset cancers. There are discussions of the latest developments and the most important cancer types for AYA, taking in the shared perspectives of adult and pediatric specialists. Throughout the book recurrent challenges to the AYA community are exposed and solutions proposed. Tumors in Adolescent and Young Adults is highly recommended to any oncologist or haematologist treating patients aged 15 to 39 diagnosed with cancer. It will also be of interest to other members of the multi-disciplinary teams involved with this patient group.