Revised 6 July 2012
Staging Diagram
The staging definitions (UICC, TNM, 7th edition) and stage groups are as follows:
T (Tumour) Definitions
T1 | Tumour ≤3 cm diameter, surrounded by lung or visceral pleura, without invasion more proximal than lobar bronchus |
T1a | Tumour ≤2 cm in diameter
|
T1b | Tumour >2 cm but ≤3 cm in diameter |
T2 | Tumour >3 cm but ≤7 cm, or tumour with any of the following features: |
| Involves main bronchus, ≥2 cm distal to carina |
| Invades visceral pleura |
| Associated with atelectasis or obstructive pneumonitis that extends to the hilar region but does not involve the entire lung |
T2a | Tumour >3 cm but ≤5 cm |
T2b | Tumour >5 cm but ≤7 cm |
T3 | Tumour >7 cm or any of the following: |
| Directly invades any of the following: chest wall, diaphragm, phrenic nerve, mediastinal pleura, parietal pericardium, main bronchus <2 cm from carina (without involvement of carina) |
| Atelectasis or obstructive pneumonitis of the entire lung |
| Separate tumour nodules in the same lobe |
T4 | Tumour of any size that invades the mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina, or with separate tumour nodules in a different ipsilateral lobe |
N (Node) Definitions
NX | Regional lymph nodes cannot be assessed. |
N0 | No regional lymph node metastases |
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 (Metastasis) Definitions
MX | Presence of distant metastasis cannot be assessed. |
M0 | No known distant metastasis. |
M1 | Distant metastasis present. |
M1a | Separate tumour nodule(s) in a contralateral lobe; tumour with pleural nodules or malignant pleural or pericardial effusion |
M1b | Distant metastasis (in extrathoracic organs) |
*The uncommon superficial 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 T1.
**Most pleural effusions associated with lung cancer are due to tumour. However, there are a few patients in whom multiple cytopathologic examinations of pleural fluid show no tumour. In these cases, 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 T1, T2, T3, or T4. Pericardial effusion is classified according to the same rules.
The letter P is used to denote classification which is determined histologically after resection. A staging diagram to assist in classification of individual nodes is appended.
Stage Groupings:TNM Subsets*
Occult carcinoma: | TX | NO | MO |
Stage 0: | TIS | N0 | M0 |
Stage IA | T1a-T1b | N0 | M0 |
Stage IB | T2a | N0 | M0 |
Stage IIA | T1a,T1b,T2a | N1 | M0 |
| T2b | N0 | M0 |
Stage IIB | T2b | N1 | M0 |
| T3 | N0 | M0 |
Stage IIIA | T1a,T1b,T2a,T2b | N2 | M0 |
| T3 | N1,N2 | M0 |
| T4 | N0,N1 | M0 |
Stage IIIB | T4 | N2 | M0 |
| Any T | N3 | M0 |
Stage IV | Any T | Any N | M1a or M1b |
Reference:
Detterbeck FC, Boffa DJ, Tanoue LT. The new lung cancer staging system. Chest 2009; 136(1) 26-71.
SCLC grows and spreads quickly. It is important to recognise this tumour because it responds readily to both chemotherapy and radiotherapy and in some cases can be cured with appropriate treatment. The Veterans Administration Lung Group system divides SCLC patients into either limited or extensive stages. More recently some cooperative groups have supported to use the TNM staging to define disease. In B.C. practice is still to define as limited or extensive.
Using current staging procedures, 30-40% of SCLC patients have limited stage SCLC. Defining limited versus extensive is important as it impacts treatment and helps predict prognosis. Limited SCLC patients fit enough to receive combined modality therapy are treated with curative intent. Extensive stage SCLC patients are generally treated with palliative intent. After the diagnosis of SCLC, accurate staging should be completed as expediently as possible.
Limited Stage Small Cell Lung Cancer
The original operational definition of limited disease was tumour quantity and configuration that could be encompassed by a "reasonable" radiotherapy treatment volume including the primary tumour site and the adjacent hilar, mediastinal and ipsilateral supraclavicular lymph nodes. The presence of massive intrathoracic tumour may preclude a "reasonable" thoracic radiotherapy volume and allow palliative therapy only.
Extensive Stage Small Cell Lung Cancer
Disease beyond the limited stage criteria is defined as extensive stage. Patients with "regional" extensive stage disease (pleural effusion, contralateral supraclavicular nodes or cervical lymph nodes) have a prognosis that is intermediate between limited and extensive and may benefit from a limited stage type treatment plan.
References:
Zelen M. Keynote address on biostatistics and data retrieval, part 3, Cancer Chemo Rep 1973;4(2):31.
Argiris A, Murren JR. Staging and clinical prognostic factors for small-cell lung cancer. Cancer J. 2001;7(5):437.
Stahel R, Thatcher N, Früh M, Le Péchoux C, Postmus PE, Sorensen JB, Felip E; Panel members.1st ESMO Consensus Conference in lung cancer; Lugano 2010: small-cell lung cancer.Ann Oncol. 2011 Sep;22(9):1973-80. Epub 2011 Jul 4.
van Meerbeeck JP, Fennell DA, De Ruysscher DK. Small-cell lung cancer. Lancet. 2011 Nov 12;378(9804):1741-55. Epub 2011 May 10.
