MESOTHELIOMA STAGES
Butchart Staging System
for Malignant Pleural Mesothelioma &
TNM Staging System for Malignant Pleural Mesothelioma
Below are the 2 most common
Mesothelioma staging systems are the Butchart system commonly referred
to as: (Stage 1 mesothelioma, Stage 2 mesothelioma, Stage 3 mesothelioma,
Stage 4 mesothelioma) and the tumor, node, metastases TNM Staging System ,T1a,T1b,T2,
T3, T4, stages Table 2 introduced by the International Mesothelioma Interest
Group. Staging is the process of finding out how far the cancer has spread.
Staging of mesothelioma is based on imaging studies such as x-rays, CT
scans, and MRI scans.
The treatment and outlook
for patients with mesothelioma largely depends on the stage (extent of
spread) of their cancer. Since pleural mesothelioma occurs most frequently
and has been studied the most, it is the only mesothelioma for which a
staging classification exists. The staging system most often used for
mesothelioma is the Butchart system. This system is based mainly on the
extent of the primary tumor mass, and divides mesotheliomas into stages
I through IV. Patients in Stage I of the Disease have a significantly
better prognosis than those with more advanced stage. However, due to
the relative rarity of this mesothelioma, exact survival information based
upon a stage is limited. Once malignant mesothelioma is found, more medical
tests are usually performed to find out if cancer cells have spread to
other parts of the body. This mesothelioma staging process is essential
so that the doctors know the correct stage of the mesothelioma cancer
in order to treat it effectively. A staging system based upon thoracic
surgery principals and clinical data is shown below:
Table 1. Butchart
Staging System for Malignant Pleural Mesothelioma
Stage |
Location |
I |
Tumor confined to the ipsilateral
pleura, lung, or pericardium |
II |
Tumor invading the chest wall
or mediastinal structures or metastases to thoracic lymph nodes |
III |
Tumor penetrating the diaphragm
to involve the peritoneum or metastases to extrathoracic lymph
nodes |
IV |
Distant blood-borne metastases |
Table 2. TNM Staging System for Malignant Pleural
Mesothelioma
Stage |
Location |
T1a |
Limited to ipsilateral parietal pleura (including
mediastinal and diaphragmatic pleura), with no involvement of visceral
pleura |
T1b |
Ipsilateral parietal pleura (including mediastinal
and diaphragmatic pleura), with scattered foci of visceral pleural
involvement |
T2 |
Ipsilateral pleural surface has at least
1 of the following:
Diaphragmatic muscle involvement
Confluent visceral pleural tumor involvement (including fissures)
Extension from visceral pleura into pulmonary parenchyma
|
T3 |
Locally advanced but resectable tumor; each
ipsilateral pleural surface has at least 1 of the following:
Involvement of the endothoracic fascia
Extension into the mediastinal fat
Solitary, completely resectable tumor focus in chest wall soft
tissues
Nontransmural involvement of the pericardium
|
T4 |
Locally advanced, technically unresectable
tumor; each ipsilateral pleural surface has at least 1 of the following:
Diffuse extension or multifocal chest wall
masses with or without rib destruction
Direct transdiaphragmatic extension into the peritoneum
Direct extension to contralateral pleura
Direct extension to 1 or more mediastinal organs
Direct extension into spine
Extension through to internal surface of pericardium, with or
without pericardial effusion or myocardial involvement
|
NX |
Regional lymph nodes not assessable |
N0 |
No regional lymph nodes metastases |
N1 |
Metastases in ipsilateral bronchopulmonary or hilar
lymph nodes |
N2 |
Metastases in subcarinal or ipsilateral mediastinal
lymph nodes, including ipsilateral internal mammary nodes |
N3 |
Metastases in contralateral mediastinal, contralateral
internal mammary, and ipsilateral or contralateral supraclavicular
lymph nodes |
MX |
Distant metastases not assessable |
M0 |
No distant metastases |
M1 |
Distant metastases present |
|
