The latest clinical method of mesothelioma staging is the Brigham System. The system was developed by the Brigham and Women's Hospital Thoracic Oncology Program, part of the Dana-Farber Cancer Institute in Boston.

The Brigham System is a four-stage program based on whether the mesothelioma can treated by surgery (i.e., its resectability), and upon the status of the patient’s lymph nodes. Staging is characterized by the following criteria:

  • Stage I: mesothelioma is resectable; no lymph node malignancy
  • Stage II: mesothelioma is resectable; lymph nodes malignant
  • Stage III: mesothelioma is not resectable and has spread to diaphragm and the peritoneum; lymph nodes around the body may be affected
  • Stage IV: mesothelioma is present in many organs and tissues