Thoracic Lymph Node Stations



N2 Nodes

N2 nodes stations are designated with a single digit

N2 nodes must lie within the mediastinal pleural envelope

1 Highest mediastinal nodes

Above the upper rim of the bracheocephalic (left innominate) vein where it ascends to the left, crossing in front of the trachea at its midline

2 Upper paratracheal nodes

Below #1 and above the upper margin of the aortic arch

3 Prevascular and retrotracheal nodes

3A: prevascular; 3P: retrotracheal.  Midline nodes are ipsilateral for both sides

4 Lower paratracheal nodes

Below #2 and above the upper margin of the upper lobe bronchus and on the left, medial to the ligamentum arteriosum.

5 Subaortic (aorto-pulmonary window)

Lateral to the ligamentum arteriosum or the aorta or the left pulmonary artery, and proximal to the first branch of the left pulmonary artery

6 Para-aortic (ascending aorta or phrenic)

Anterior and lateral to the ascending aorta and the aortic arch or the innominate artery beneath a line tangential to the upper margin of the aortic arch

7 Subcarinal nodes

Caudal to the carina of the trachea, but not associated with the lower lobe bronchi or arteries within the lung

8 Paraesophageal nodes (below carina)

Adjacent to the wall of the esophagus, excluding subcarinal nodes

9 Pulmonary ligament nodes

Within the pulmonary ligament, including those in the posterior wall and lower part of the inferior pulmonary vein


N1 Nodes

N1 nodes are designated with two digits

N1 nodes must lie distal to the mediastinal pleural reflection

10 Hilar nodes

Distal to the mediastinal pleural reflection, adjacent to the proximal lobar bronchi and the bronchus intermedius

11 Interlobar nodes

Lying between lobar bronchi

12 Lobar nodes

Adjacent to the distal lobar bronchi

13 Segmental nodes

Adjacent to the segmental bronchi

14 Subsegmental nodes

Around the subsegmental bronchi


after Mountain et. al.