[Diagnosis of diffuse pleural mesotheliomas]

Main clinical symptoms and signs in diffuse malignant pleura mesotheliomas are thoracic pain (58%) and gradually increasing dyspnoea (50%). Pleural effusion is the most frequent x-ray manifestation (80%), but it is haemorrhagic in only 50% of the cases. Cytology has a sensitivity of approx. 50%; with the epithelial type it yields definitely better results (76%) than with the biphasic (49%) or fibrous (25%) types. The carcinoembryonic antigen level is usually low in the effusion, but enhanced values do not exclude a diffuse malignant pleura mesothelioma. For differentiation against metastasised adenocarcinomas, which is often difficult, it is recommended to effect histological examination of the tumour tissue obtained either by pleura punch biopsy (sensitivity 40-50%) or by thoracoscopy (sensitivity 90-95%). In this manner, accurate staging is possible in conjunction with CT. Particularly in case of fibrous growth, it is sometimes only thoracotomy that enables final diagnostic clarification.