CONSIDERATION OF DOSE LIMITS FOR ORGANS AT RISK OF THORACIC RADIOTHERAPY: ATLAS FOR LUNG, PROXIMAL BRONCHIAL TREE, ESOPHAGUS, SPINAL CORD, RIBS, AND BRACHIAL PLEXUS

• Authors: Feng-Ming (Spring) Kong, University of Michigan; Timothy Ritter, University of Michigan; Douglas J. Quint, University of Michigan; Suresh Senan, VU University Medical Center; Laurie E. Gaspar, University of Colorado; Ritsuko U. Komaki, University of Texas; Coen W. Hurkmans, Catharina Hospital; Robert Timmerman, University of Texas; Andrea Bezjak, Princess Margaret Hospital; Jeffrey D. Bradley, Washington University; Benjamin Movsas, Henry Ford Hospital; Lon Marsh, University of Michigan; Paul Okunieff, University of Florida; Hak Choy, University of Texas; Walter Curran, Emory University
• Journal Title: International Journal of Radiation Oncology - Biology - Physics
• Volume: Volume 81, Number 5
• Publisher: Elsevier | 2011-12-01, Pages 1442-1457
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.ijrobp.2010.07.1977
• Subjects: Health Sciences, Oncology; Health Sciences, Pathology
• Keywords: Science & Technology; Life Sciences & Biomedicine; Oncology; Radiology, Nuclear Medicine & Medical Imaging; Atlas; Lung; Esophagus; Spinal cord; Brachial plexus; VOLUME HISTOGRAM ANALYSIS; RADIATION PNEUMONITIS; DOSIMETRIC FACTORS; CANCER NSCLC; CONCURRENT CHEMOTHERAPY; PREDICTORS; TOXICITY; THERAPY; INJURY; IRRADIATION

Abstract

Purpose: To review the dose limits and standardize the three-dimenional (3D) radiographic definition for the organs at risk (OARs) for thoracic radiotherapy (RT), including the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus. Methods and Materials: The present study was performed by representatives from the Radiation Therapy Oncology Group, European Organization for Research and Treatment of Cancer, and Soutwestern Oncology Group lung cancer committees. The dosimetric constraints of major multicenter trials of 3D-conformal RT and stereotactic body RT were reviewed and the challenges of 3D delineation of these OARs described. Using knowledge of the human anatomy and 3D radiographic correlation, draft atlases were generated by a radiation oncologist, medical physicist, dosimetrist, and radiologist from the United States and reviewed by a radiation oncologist and medical physicist from Europe. The atlases were then critically reviewed, discussed, and edited by another 10 radiation oncologists. Results: Three-dimensional descriptions of the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus are presented. Two computed tomography atlases were developed: one for the middle and lower thoracic OARs (except for the heart) and one focusing on the brachial plexus for a patient positioned supine with their arms up for thoracic RT. The dosimetric limits of the key OARs are discussed. Conclusions: We believe these atlases will allow us to define OARs with less variation and generate dosimetric data in a more consistent manner. This could help us study the effect of radiation on these OARs and guide high-quality clinical trials and individualized practice in 3D-conformal RT and stereotactic body RT.