Loading

wait a moment

Staging lung cancer: Current controversies and strategies (2)

The initial tumour-node-metastases (TNM) system for staging cancer was described in 1946 by Denoix. The American Joint Committee for Cancer Staging and End Results Reporting (AJCC) applied the TNM descriptors to lung cancer. Subsequently, it became apparent that, within the same clinical stage, there were subsets with significantly different prognoses. In 1986, Mountain presented the currently used staging system, a combined effort by the AJCC and the International Union Against Cancer (Tables 1,2). An explanation of the classifications within this paper are outlined in Tables 1 and 2. Within stage III there are further clinically distinct subgroups, each with different prognoses and treatment responses (Table 3). Therefore, the current TNM system will probably undergo further modification.

The staging process can be broken down into a clinical stage (cTNM) and a pathological stage (pTNM). cTNM, determined by clinical, radiographical and invasive studies, is used to plan the optimal therapeutic approach. pTNM, determined after surgery, suggests the prognosis and the role of adjuvant regimens (Table 4) . Analysis of the resected specimen by using cell biological techniques may be added to the assesment of pTNM and affect postoperative treatment planning . The TNM system is applicable to both NSCLC and small cell lung cancer (SCLC). SCLC, however, is usually described as ‘limited’ or ‘extensive’ based on whether it can be encompassed by one radiation port. As important as these methodologies are, it is equally important to determine whether the patient has sufficient cardiopulmonary reserves to undergo a resection. You will love this opportunity to shop with best pharmacy on the internet and pay less every time you visit: buy flovent inhaler to discover exactly how much less you could be spending while still getting your treatment exactly the way you need it.

Table 1. Tumour-node-metastases classification for staging lung cancer

T: Primary tumour
TX Tumour proven by the presence of malignant cells in bronchopulmonary secretions but not visualized radiographically or bronchoscopically, or any tumour that cannot be assessed, as in a retreatment staging
TO No evidence of primary tumour
TIS Carcinoma in situ
T1 Tumour is 3.0 cm or less in greatest dimension, surrounded by lung or visceral pleura and without evidence of invasion proximal to a lobar bronchus at bronchoscopy
T2 Tumour is more than 3.0 cm in greatest dimension or of a size that either invades the visceral pleura or has associated atelectasis, or obstructive pneumonitis extending to the hilar region. At bronchoscopy, the proximal extent of demonstrable tumour must be within a lobar bronchus or at least 2.0 cm distal to the carina. Any associated atelectasis or obstructive pneumonitis must involve less than an entire lung
T3 Tumour of any size with direct extension into the chest wall (including superior sulcus tumours), diaphragm, or the mediastinal pleura or pericardium without involving the heart, great vessels, trachea, esophagus or vertebral body, or a tumour in the main bronchus within 2 cm of the carina without involving the carina
T4 Tumour of any size with invasion of the mediastinum or involving heart, great vessels, trachea, esophagus or vertebral body or carina, or presence of malignant pleural effusion
N: Nodal involvement
NO No demonstrable metastasis to regional lymph nodes
N1 Metastasis to lymph nodes in the peribronchial or ipsilateral hilar region, or both, including direct extension
N2 Metastasis to ipsilateral mediastinal and subcarinal lymph nodes
N3 Metastasis to contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph nodes
M: Distant metastasis
MO No (known) distant metastasis
M1 Distant metastasis present

Table 2. Tumour-node-metastases grouping into stages

Stage Tumoursubgroup Nodalsubgroup Metastasessubgroup
Occult carcinoma TX N0 M0
Stage 0 TIS N0 M0
Stage I T1 N0 M0
T2 N0 M0
Stage II T1 N1 M0
T2 N1 M0
Stage IIIa T3 N0 M0
T3 N1 M0
T1 to T3 N1 to N3 M0
Stage IIIb Any T N3 M0
T4 Any N M0
Stage IV Any T Any N M1

See Table 1 for explanation of subgroups

Table 3. Clinically distinct subgroups within stage III nonsmall cell carcinoma lung cancer

Stage Tumour and nodal subgroups Description
IIIA T1-3 N0-1 Peripheral lesion with chest wall invasion or less than 2 cm from the carina. Some superior sulcus tumours (resectable)
T1-3 N2 Prognosis and therapy defined by N2 status (staging of N2 nodes determines whether surgery can be primary treatment or whether surgery can be contemplated as part of neoadjuvant regimens)
IIIB T4 N0-2 Locally invasive primary tumour without malignant effusion (may be resectable, thoracoscopy may help define chest and/or mediastinal invasion, while bronchoscopy can define the extent of carinal and tracheal involvement)
T1-4 N3 Prognosis and therapy defined by N3 disease (surgery not an option as primary treatment; inclusion in clinical trials may be an option)
T4 N0-3 Malignant pleural effusion (T4) (not resectable, palliative treatment only)

Adapted with permission from reference 10

 

TABLE 5

Methods of staging

NoninvasiveClinical examination Chest x-ray Nuclear studies Magnetic resonance imaging Computer assisted tomography scan Positron emission tomography scan Invasive

Bronchoscopy

Needle aspiration

Cervical mediastinoscopy

Extended cervical mediastinoscopy

Mediastinotomy

Thoracoscopy

Thoracotomy

Adapted with permission from reference 10

Leave a Reply

Your email address will not be published. Required fields are marked *