TNM Clinical Classification


T – Primary Tumour

  • TX - Primary tumour cannot be assessed, or tumour proven by the presence of malignant cells in sputum or bronchial washings but not visualized by imaging or bronchoscopy
  • T0 - No evidence of primary tumour
  • Tis - Carcinoma in situ
  • T1 - Tumour 3 cm or less in greatest dimension, surrounded by lung or visceral pleura, without bronchoscopic evidence of invasion more proximal than the lobar bronchus (i.e., not in the main bronchus)
    • T1a - Tumour 2 cm or less in greatest dimension1
    • T1b - Tumour more than 2 cm but not more than 3 cm in greatest dimension
  • T2 - Tumour more than 3 cm but not more than 7 cm; or tumour with any of the following features2:
    • Involves main bronchus, 2 cm or more distal to the carina
    • Invades visceral pleura
    • Associated with atelectasis or obstructive pnemonitis that extends to the hilar region but does not involve the entire lung
      • T2a - Tumour more than 3 cm but not more than 5 cm in greatest dimension
      • T2b - Tumour more than 5 cm but not more than 7 cm in greatest dimension
  • T3 - Tumour more than 7 cm or one that directly invades any of the following: chest wall (including superior sulcus tumours), diaphragm, phrenic nerve, mediastinal pleura, parietal pericardium; or tumour in the main bronchus less than 2 cm distal to the carina1 but without involvement of the carina; or associated atelectasis or obstructive pneumonitis of the entire lung or separate tumour nodule(s) in the same lobe as the primary.
  • T4 - Tumour of any size that invades any of the following: mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, oesophagus, vertebral body, carina; separate tumour nodule(s) in a different ipsilateral lobe to that of the primary.

N – Regional Lymph Nodes

  • NX - Regional lymph nodes cannot be assessed
  • N0 - No regional lymph node metastasis
  • N1 - Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension
  • N2 - Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s)
  • N3 - Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph node(s)

M – Distant Metastasis

  • M0 - No distant metastasis
  • M1 - Distant metastasis
    • M1a - Separate tumour nodule(s) in a contralateral lobe; tumour with pleural nodules or malignant pleural or pericardial effusion3
    • M1b - Distant metastasis

Notes:

  • The uncommon superficial spreading tumour of any size with its invasive component limited to the bronchial wall, which may extend proximal to the main bronchus, is also classified as T1a.
  • T2 tumours with these features are classified T2a if 5 cm or less or if size cannot be determined, and T2b if greater than 5 cms but not larger than 7 cms.
  • Most pleural (pericardial) effusions with lung cancer are due to tumour. In a few patients, however, multiple microscopical examinations of pleural (pericardial) fluid are negative for tumour, and the fluid is non-bloody and is not an exudate. Where these elements and clinical judgment dictate that the effusion is not related to the tumour, the effusion should be excluded as a staging element and the patient should be classified as M0.

  • Landmarks and description for regional LN
    Nodal station Description Definition
    #1
    (Left/Right)    		 Low cervical, supraclavicular and sternal notch nodes Upper border: lower margin of cricoid cartilage
    Lower border: clavicles bilaterally and, in the midline, the upper border of the manubrium
    #L1 and #R1 limited by the midline of the trachea.
    #2
    (Left/Right)    		 Upper paratracheal nodes 2R: Upper border: apex of lung and pleural space and, in the midline, the upper border of the manubrium
    Lower border: intersection of caudal margin of innominate vein with the trachea
    2L: Upper border: apex of the lung and pleural space and, in the midline, the upper border of the manubrium
    Lower border: superior border of the aortic arch
    As for #4, in #2 the oncologic midline is along the left lateral border of the trachea.
    #3 Pre-vascular and retrotracheal nodes
    3a: Prevascular
    On the right
    upper border: apex of chest
    lower border: level of carina
    anterior border: posterior aspect of sternum
    posterior border: anterior border of superior vena cava
    3p: Retrotracheal
    upper border: apex of chest
    lower border: carina    		 On the left
    upper border: apex of chest
    lower border: level of carina
    anterior border: posterior aspect of sternum
    posterior border: left carotid artery
    #4
    (Left/Right)    		 Lower paratracheal nodes 4R: includes right paratracheal nodes, and pretracheal nodes extending to the left lateral border of trachea
    upper border: intersection of caudal margin of innominate vein with the trachea
    lower border: lower border of azygos vein
    4L: includes nodes to the left of the left lateral border of the trachea, medial to the ligamentum arteriosum
    upper border: upper margin of the aortic arch
    lower border: upper rim of the left main pulmonary artery
    #5 Subaortic (aorto- pulmonary window) Subaortic lymph nodes lateral to the ligamentum arteriosum
    upper border: the lower border of the aortic arch
    lower border: upper rim of the left main pulmonary artery
    #6 Para-aortic nodes (ascending aorta or phrenic) Lymph nodes anterior and lateral to the ascending aorta and aortic arch
    upper border: a line tangential to the upper border of the aortic arch
    lower border: the lower border of the aortic arch
    #7 Subcarinal nodes upper border: the carina of the trachea
    lower border: the upper border of the lower lobe bronchus on the left; the lower border of the bronchus intermedius on the right
    #8
    (Left/Right)    		 Para-esophageal nodes (below carina) Nodes lying adjacent to the wall of the esophagus and to the right or left of the midline, excluding subcarinal nodes
    upper border: the upper border of the lower lobe bronchus on the left; the lower border of the bronchus intermedius on the right
    lower border: the diaphragm
    #9
    (Left/Right)    		 Pulmonary ligament nodes Nodes lying within the pulmonary ligament
    upper border: the inferior pulmonary vein
    lower border: the diaphragm
    #10
    (Left/Right)    		 Hilar nodes Includes nodes immediately adjacent to the mainstem bronchus and hilar vessels including the proximal portions of the pulmonary veins and main pulmonary artery
    upper border: the lower rim of the azygos vein on the right; upper rim of the pulmonary artery
    on the left lower border: interlobar region bilaterally
    #11 Interlobar nodes Between the origin of the lobar bronchi
    *#11s: between the upper lobe bronchus and bronchus intermedius on the right
    *#11i: between the middle and lower lobe bronchi on the right
    *optional sub-categories