Patients presented with pleural effusions associated with pleural thickening , the cause most probably fall in the neoplastic category especially if the thickening is nodular. The differential diagnosis of pleural thickening would include benign entities such as recurrent inflammation, recurrent pneumothoracies, seqaule of empyema or hemothorax and could be related to occupational or inhalational diseases such as asbestosis or silicosis. On the other hand, malignancy should be suspected if the pleural thickening is nodular or it is associated with pleural effusion. The differential diagnosis would include, primary neoplastic processes like mesothelioma, lymphoma and invasive thymoma or secondaries from bronchogenic , breast, prostate, ovarian, gastrointestinal or renal cell carcinomas. Thoracic splenosis is a rare cause of plural nodular thickening.
Left pleural biopsy reveled invasive malignant neoplasm consistent with mesothelioma, epithelioid type.