Addressing the challenge of proper delineation of lymph node stations in modern radiotherapy for lung cancer

We greatly appreciate the recent publication of a Japan Lung Cancer Society and Japanese Society for Radiation Oncology consensus-based computed tomographic atlas for defining regional lymph node stations (LNSs) for radiotherapy for lung cancer. This atlas is based on the International Association for the Study of Lung Cancer (IASLC) consensus lymph node map, which resolved differences between the Japanese and American classification and was incorporated into the seventh edition of the TNM staging system. The authors must be commended for providing a very clear, comprehensive presentation of the borders of the mediastinal and hilar LNSs, using a multidisciplinary approach. The Atlas created by Itazawa et al. is the second published consensus-based atlas for defining the LNSs for lung cancer radiotherapy according to the IASLC-endorsed LNS map. The differences between the two published atlases of LNS delineation in radiation oncology are discussed.