Since the first edition of this book in 2012, the field of molecular pathology has expanded exponentially. The advent of complete cancer genome sequencing, new diagnostic molecular tests, and biomarkers for targeted therapy and immunotherapy have demonstrated the importance of molecular tools both in patient care and in the practice of pathology. Furthermore, the development of many new molecular technologies has revolutionized the practice of modern pathology. The rapid growth of this field has led to an expansion of knowledge of molecular processes and many more clinical applications in our daily practice of surgical pathology. Thus, this updated second edition of Molecular Surgical Pathology aims to serve as the best available “quick reference” for pathologists, oncologists, geneticists, primary care physicians, and other medical professionals with an interest in this specialty. Molecular Surgical Pathology 2nd Edition focuses on the practical utility of molecular techniques and on molecular biomarkers for the practicing surgical pathologist. The emphasis is on the impact of molecular pathology for tumor classification, diagnosis and differential diagnosis, as well as its implications for patient management and personalized care. This concise overview of molecular surgical pathology and molecular classification of tumors of different organ sites will help not only practicing physicians, but also those in training, including residents and fellows in various disciplines.