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LUNG CANCER
A Handbook for Staging, Imaging, and Lymph Node Classification
by Clifton F. Mountain, MD; Herman I. Libshitz, MD; and Kay E. Hermes
Contents | About the Author(s) | Dedication and Acknowledgment
 Illustrations and Imaging
page 22 

N1

Fig. 22: Diagram, N1 disease. Metastasis to lymph nodes in the peribronchial or the ipsilateral hilar region or both, including direct extension, is classified N1.

The clinical classification of N1 disease usually represents metastasis involving the hilar lymph nodes, defined as the proximal lobar nodes, distal to the mediastinal pleural reflection, and the nodes adjacent to the bronchus intermedius on the right. Radiographically, the hilar shadow may be created by enlargement of both hilar and interlobar nodes. Infrequently, peribronchial, segmental, and subsegmental lymph nodes may be seen on conventional and computed tomographic scans.

Fig. 23: Computed tomographic scan of the chest shows extensive left hilar adenopathy in a patient with a left upper lobe bronchogenic carcinoma, N1 disease.

Copyright © 1999 - 2003 by CF Mountain and HI Libshitz, Houston, Texas. All rights reserved.

Printed in the United States of America by Charles P. Young Company. No part of this manual may be reproduced by any means without the prior written consent of the authors.