Intensity modulated radiation therapy (IMRT) offers an excellent opportunity to optimize the therapeutic ratio in radiation oncology through maximizing tumor coverage and sparing normal tissue by appropriate clinical input and precise computer algorithms. This cutting edge technology is being used not only in academic institutions, but also in community clinics. The increasing need for essential practical guidelines to address clinical indication, imaging interpretation, target delineation, and plan optimization has inspired the genesis of the 2^nd edition of Practical Essentials of Intensity Modulated Radiation Therapy.

In this book, a practical overview of IMRT physics, quality assurance, and treatment planning and optimization are first given in Chapters 1 and 2. Because successful implementation of IMRT depends on proficient understanding in anatomical imaging (computed tomography and magnetic resonance imaging), pertinent information to update readers on this topic is provided in Chapters 3 and 4 for brain, head and neck, urological, and gynecological cancers. Further, integrating functional imaging to assist in more accurate target delineation or for dose escalation may soon be a clinical reality, we elicit the process and caution of incorporating functional images for IMRT planning in Chapter 5.

In the first edition, we provided practical guidance for IMRT in the management of head and neck cancer patients. Because IMRT utilization has become more widespread, the 2^nd edition expands the breadth of coverage to include concise, relevant overviews of the natural course, diagnostic criteria, therapeutic options, as well as up-to-date IMRT treatment guidelines for other various tumor sites. Chapters 6, 7, 8, 9, 10, 11, 12, 13 and 14 provide updated information and results on head and neck cancers with a new Chapter 13 on thyroid carcinoma. New chapters encompassing breast, thoracic, esophageal, prostate, and gynecological cancers are included with high quality of illustration to assist reader in target determination and delineation (Chapters 15, 16, 17, 18 and 20, 21).

We emphasize the importance of understanding basic anatomy and the corresponding imaging sections that are being used for target and normal tissue determination and delineation. Accordingly, more than 350 full-color, detailed illustrations are provided to clarify each step in the clinical implementation of IMRT. We believe this new edition will assist residents, fellows, and clinicians of radiation oncology in learning the practical essentials for the clinical evaluation, decision-making, and technical proficiency of IMRT for multiple disease sites. The information presented in this book will continue to be refined, as rapid accumulation of clinical experience and evolution of imaging and targeting techniques have become so evident.