Malignant pleural mesothelioma (MPM) is an uncommon and usually fatal primary neoplasm of the pleura. In the past, response to standard therapy has been poor [1-3], but recent studies suggest that some patients may benefit from various therapeutic options, including surgical resection, combined technique treatment, and immunotherapy [4-7]. With improvements in therapy, an accurate, widely accepted staging system will be important in selecting homogeneous groups of patients for entry into clinical trials. Multiple staging systems have previously been proposed for MPM, but none are universally used [8].