This volume is part of a series on pathology of tumours in laboratory animals. The mouse remains one of the most commonly used experimental models for both routine testing of possibly carcinogenic chemicals and research on mechanisms of tumour induction and development. This had led to an ever-growing body of knowledge about mouse tumours and tumorigenesis, that provides the basis for this new edition. New discoveries and new classifications are incorporated wherever relevant, so as to ensure that this series, of which this is the second volume, will reflect the latest concepts and practices in this area of research.