Book excerpt: This book covers almost all fields of cancer genetics and genomics for personalized medicine. Targeted therapy, or precision medicine, or personalized medicine is becoming a standard treatment for many diseases, including cancer. However, how much do we know about the personalized medicine approach? This lucid book helps undergraduate and graduate students, professional researchers, and clinicians to better understand the key concept of personalized medicine. The most up-to-date topics on personalized medicine in this book cover the recent trends in and updates on lung, gastric, liver, breast, and other types of cancers. Circulating tumor cell, cell-free circulating DNA, and microRNAs are discussed as new diagnostic and prognostic markers for cancer. The avatar mouse model is also discussed for maximizing treatment efficacy and prognosis prediction, and so is microenvironment as a drug resistance mechanism. With classical and new pathological approaches, the book provides a systemic overview of personalized immunotherapies and hyperthermic intraperitoneal chemotherapy, followed by new emerging fields of hereditary cancer, thereby equipping readers to eventually contribute in developing more advanced tools and therapies for curing cancer.