T (sum of the extent of spread of the primary tumour) | |
TXa | The main tumour cannot be assessed for some reason |
T0a | No evidence of a main tumour |
T1a | MMT involvement of the pleura on one side of the chest (even the diaphragmatic or mediastinal pleura) |
T2a | T1 + involvement of chest wall, diaphragmatic and mediastinal pleura and at least one of diaphragm or lung infiltration |
T3a | T2 + infiltration of at least one of the following: endothoracic fascia, fatty mediastinal tissue, a SINGLE place in the deeper layers of the chest wall, surface of the pericardium |
T4b | T3 + infiltration of at least one of the following: more than one place in the deeper layers of the chest wall, the peritoneum, any organs in the mediastinum, the spine, the other side of the chest, the heart muscle |
N (regional lymph nodes involvement) | |
NX | The nearby lymph nodes cannot be assessed |
N0 | No spread to the nearby lymph nodes |
N1 | Spread to the hilar or bronchial lymph nodes on the same side as the primary tumour |
N2 | Spread to other lymph nodes on the same side as the primary tumour (subcarinal, mediastinal, internal mammary and peridiaphragmatic) |
N3 | Spread to the supraclavicular lymph nodes and/or to those on the opposite side to the primary tumour |
M (primary tumour spread to the other organs of the body) | |
M0 | No spread to distant organs or areas |
M1 | Spread to distant sites (lymph nodes and organs) |