Pleural Mesothelioma

TNM 7 classification

TNM 6 classification

1. Rules for Classification

The classification applies only to malignant mesothelioma of the pleura. There should be histological confirmation of the disease.

The following are the procedures for assessing T, N, and M categories:

T categories. Physical examination, imaging, endoscopy, and/or surgical exploration
N categories. Physical examination, imaging, endoscopy, and/or surgical exploration
M categories. Physical examination, imaging, and/or surgical exploration

2. Regional Lymph Nodes

The regional lymph nodes are the intrathoracic, internal mammary, scalene, and supraclavicular nodes.

3. TNM Clinical Classification

3.1. T - Primary Tumour

TX. Primary tumour cannot be assessed

T0. No evidence of primary tumour

T1. Tumour involves ipsilateral parietal pleura, with or without focal involvement of visceral pleura
     T1a. Tumour involves ipsilateral parietal (mediastinal, diaphragmatic) pleura. No involvement of visceral pleura
     T1b. Tumour involves ipsilateral parietal (mediastinal, diaphragmatic) pleura, with focal involvement of the visceral pleura

T2. Tumour involves any ipsilateral pleural surfaces, with at least one the following:

• confluent visceral pleural tumour (including the fissure)
  
• invasion of diaphragmatic muscle
  
• invasion of lung parenchyma
  

T3^*. Tumour involves any ipsilateral pleural surfaces, with at least one of the following:

• invasion of endothoracic fascia
  
• invasion into mediastinal fat
  
• solitary focus of tumour invading soft tissues of the chest wall
  
• non-transmural involvement of the pericardium
  

T4^~. Tumour involves any ipsilateral pleural surfaces, with at least one of the following:

• diffuse or multifocal invasion of soft tissues of chest wall
  
• any involvement of rib
  
• invasion through diaphragm to peritoneum
  
• invasion of any mediastinal organ(s)
  
• direct extension to contralateral pleura
  
• invasion into the spine
  
• extension to internal surface of pericardium
  
• pericardial effusion with positive cytology
  
• invasion of myocardium
  
• invasion of brachial plexus
  

Notes:
     ^*T3 describes locally advanced, but potentially resectable tumour
     ^~T4 describes locally advanced, technically unresectable tumour

3.2. N - Regional Lymph Nodes

NX. Regional lymph nodes cannot be assessed
N0. No regional lymph node metastasis
N1. Metastasis in ipsilateral bronchopulmonary and/or hilar lymph node(s)
N2. Metastasis in subcarinal lymph node(s) and/or ipsilateral internal mammary or mediastinal lymph node(s)
N3. Metastasis in contralateral mediastinal, internal mammary, or hilar node(s) and/or ipsilateral or contralateral supraclavicular or scalene lymph node(s)

3.3. M - Distant Metastasis

MX. Distant metastasis cannot be assessed
M0. No distant metastasis
M1. Distant metastasis

4. pTNM Pathological Classification

The pT, pN, and pM categories correspond to the T, N, and M categories.

See also: Additional site-specific recommendations for pT and pN

5. Stage Grouping

Stage IA T1a N0 M0 Stage IB T1b N0 M0 Stage II T2 N0 M0 Stage III T1. T2 N1 M0 T1. T2 N2 M0 T3 N0. N1. N2 M0 Stage IV T4 Any N M0 Any T N3 M0 Any T Any N M1

6. Summary

Pleural Mesothelioma T1 Ipsilateral parietal pleura T1a No visceral pleura T1b Visceral pleura T2 Ipsilateral lung, diaphragm, confluent involvement of visceral pleura T3 Endothoracic fascia, mediastinal fat, focal chest wall, non-transmural pericardium T4 Contralateral pleura, peritoneum, rib, extensive chest wall or mediastinal invasion, myocardium, brachial plexus, spine, transmural pericardium, malignant pericardial effusion N1 Ipsilateral bronchopulmonary, hilar N2 Subcarinal, ipsilateral mediastinal, internal mammary N3 Contralateral mediastinal, internal mammary, hilar; ipsi/contralateral supraclavicular, scalene