Butchart Mesothelioma Staging System
A Guide to the Stages of Mesothelioma.
The oldest staging system and still used quite frequently is the Butchart System which is based mainly on the extent of primary tumor mass and divides mesothelioma into four stages.
Stages one through four of the Butchart system are as follows:
Stage I: The mesothelioma can be found within the pleura on one side of the chest. It may also involve the lung, pericardium, or diaphragm on the same side.
Stage II: The mesothelioma invades the chest wall or involves the esophagus, heart, or pleura on both sides. The lymph nodes in the chest may also be involved.
Stage III: Mesothelioma has penetrated through the diaphragm into the peritoneum. Lymph nodes beyond those in the chest may also be involved.
Stage IV: There is evidence of distant metastases.

