The American Thoracic Society lymph node map: a CT demonstration.

It is now a decade since the American Thoracic Society (ATS) lymph node map was first described. Recently it has been upgraded to include supraclavicular and superior diaphragmatic lymph nodes. By standardising terminology the map aids in the provision of a more valid data base to evaluate diagnostic techniques and therapeutic protocols. Despite these potential benefits the map has failed to gain widespread use amongst European radiologists. This essay illustrates the relationship of the nodal stations to normal anatomy utilizing calcified nodes on CT scans. The ease with which the map can be applied to cross-sectional anatomy is emphasized. It is hoped that the images will act as a teaching aid to promote greater acceptance and use of the ATS map. The relationship of the nodal stations to the new American Joint Classification of disease extent is also outlined.