Diagnosis and staging of pleural mesothelioma

: Accurate diagnosis and staging are very important for the treatment of pleural mesothelioma. In particular, surgical indications based on diagnosis and staging must be determined carefully, since extrapleural pneumectomy (EPP) is a highly invasive surgical mode. Sufficient biopsy specimens to make a differential diagnosis of this disease should be obtained during video-assisted thoracoscopic surgery (VATS). Currently, the final diagnosis of mesothelioma is based not only on the results of hematoxylin and eosin staining but also of immunostaining using several differential markers. The International Mesothelioma Interest Group (IMIG) classification is widely used for the TNM staging of pleural mesothelioma. The IMIG classification is now applied to clinical staging with the aid of computed tomography and positron-emission tomography images, but the accuracy and usefulness of this classification for surgical indications and outcomes must be improved in future. Extended preoperative staging, for example, mediastinoscopy, contralateral VATS, and laparoscopy, are now selectively performed for the precise diagnosis of potentially resectable mesothelioma.