Primary pleural tumor is

Ref:Textbook of pathology (Harsh mohan) 6th edition,page no.505 TUMOURS OF PLEURA Pleural tumours may be primary or secondary. In line with pulmonary tumours, the secondary tumours in the pleura are more common. The only impoant primary tumour of pleura is mesothelioma. MESOTHELIOMA Mesothelioma is an uncommon tumour arising from mesothelial lining of serous cavities, most often in pleural cavity, and rarely in peritoneal cavity and pericardial sac. Mesotheliomas are of 2 types--benign (solitary) and malignant (diffuse). The biologic behaviour of pleural mesotheliomas is usually predicted by their gross appearance--those forming solitary, discrete masses are generally benign, whereas those which grow diffusely are usually malignant.