[Diagnosis of malignant pleural mesothelioma--thoracoscopic biopsy and tumor marker].

Diagnosis and treatment of malignant pleural mesotheliomav (MPM) are quite difficult. Pleural effusion or pleural thickening on plain chest x-ray is frequently observed in patients with MPM. Pleural effusion could be examined with aspiration and valuable information could be obtained. As to pleural thickening, contrast enhanced computed tomography is the most suitable modality for investigation. However, for the definitive diagnosis of MPM, video-assisted thoracoscopic surgery (VATS) is necessary. VATS biopsy offers enough tissue for pathological investigation, such as immunehistochemistry. Differential diagnosis between MPM and other malignancy is sometimes difficult, and erroneous results could be found without enough tissue. Sensitivity in the diagnosis of MPM with VATS is reported to be over 90%. Complication following VATS procedures is relatively rare. Thus VATS biopsy is strongly recommended for patients with suspected pleural effusion. Tumor markers, such as osteopontin and mesothelin, could be candidates for evaluating MPM without invasive diagnostic workup.