Oncology is a branch of medicine which is concerned with the prevention, diagnosis, and treatment of cancer. The term, cancer, refers to the diseases associated with the abnormal cell growth in the body, which have the potential to invade or spread to other parts. A medical practitioner who has specialized in this field is called an oncologist. Smoking or the intake of tobacco in other forms is considered to be the leading cause of cancer. Other risk factors include obesity and alcohol consumption. Cancer can be potentially treated by chemotherapy, radiation therapy, surgery, targeted therapy, hormonal therapy and synthetic lethality. The preferred mode of treatment varies according to the location and stage of the disease. The performance status of the patient is also taken into consideration. Cancer patients experience pain due to the tumor infiltrating or compressing nearby body parts, or due to the treatment or diagnostic procedure performed. Cancer pain management is therefore an essential aspect of cancer care. This book contains some path-breaking studies in the field of oncological medicine. Such selected concepts that redefine oncological medicine have been presented in it. The topics covered in this book offer the readers new insights in the field of oncological medicine.