A Guide for Delineation of Lymph Nodal Clinical Target Volume in Radiation Therapy

This book will facilitate the understanding of cross-sectional anatomy details and assist radiation oncologists in the difficult task of a detailed delineation of lymph node targets in multiple anatomical locations.
It opens with a brief overview of the anatomy of the lymphatic system, followed by the main anatomical classifications involving the lymph drain in four main regions (head and neck, mediastinum, superior abdomen, pelvis) and describes the spreading patterns of the different cancers. Based on the close collaboration between radiologists and radiation oncologists, explicit instructions for the delineation of lymph nodal clinical target volumes are proposed to obtain a more accurate and consistent definition of these volumes of interest. In addition, axial topographic reference points for anatomical boundaries of regional lymph nodes are presented in illustrative tables. This book will be a valuable aid in accurate image-based radiation therapy planning for young as well as for more experienced radiation oncologists.

Image-guided 3D Conformal or Intensity Modu- by the various classifcation systems, which might lated Radiation Terapy aims to deliver high doses be hard to fnd in scans performed without contrast of radiation to the tumor, while trying to maintain medium. dose levels to healthy tissue within tolerable limits. Together with experienced radiologists for each Terefore, it is of key importance to defne the dif- anatomical region, we have developed a set of st- ferent target volumes, gross tumor volume (GTV), dards for the acquisition of planning CT images, clinical target volume (CTV), planning target vol- standardizing the parameters for scan performance ume (PTV), and organs at risk (OARs), on the basis and those concerning patient positioning and - of in-depth knowledge of the human anatomy, of mobilization. anatomicoradiological aspects, and of anatomical In the second section of the book we describe the and geometric variations during the radiation plan- role and importance of radiological imaging in ta- ning and treatment. get defnition, including lymph nodes, especially for We have prepared this guide to meet the needs image-guided radiation therapy (IGRT).

Detailed delineation of lymph node targets in multiple anatomical locations Valuable aid in accurate image based radiation therapy treatment planning Enhanced treatment outcome, based on delivery of adequate doses of irradiation to lymph nodes at risk Decreased morbiditiy and better quality of life, by selectively irradiating outlined lymph nodes at risk

Inhalt
General Considerations.- Anatomy.- Lymph Node Classification.- Anatomicoradiological Boundaries.- Planing CT: Technical Notes.- Target Volume Delineation in Modern Radiation Therapy.- Critical Importance of Target Definition, Including Lymph Nodes, in Image-Guided Radiation Therapy.- Axial CT Radiological Anatomy.- Head and Neck Lymph Nodes.- Mediastinal Lymph Nodes.- Upper Abdominal Region Lymph Nodes.- Pelvic Lymph Nodes.- Digitally Reconstructed Radiographs (DRRs).