In the past few years, a remarkable increase in knowledge of microscopic study of brain tumors has been witnessed. Treatments like angiogenesis and immunotherapy have also been tagged important. Along with this, new pathways leading to detailed study and importance of stem cells and microRNAs have been made. Detailed information about the reaction of tumors to chemotherapy and radiation therapy has been provided. Tumors, which are a challenge to humankind, can be combated with these new effectual regimen methods. This book provides an insight into up-to-date information related to novel anticancer agents, MicroRNAs, pediatric brain tumors, radio resistance of brain tumors and stem cells.