Pleural effusion: what lies underneath?

Malignant mesothelioma is a tumour of serous surfaces mainly arising at the pleura or the peritoneum. The diagnosis encompasses multiple problems as there is no pathognomonic hallmark for the disease, there are multiple histological types and the differentiation from other tumours, such as adenocarcinoma or metastatic pleural disease, can represent quite a challenge. Usually a diagnosis of malignant mesothelioma carries a dismal prognosis with scarce therapeutical options.The present report concerns a patient with a diagnosis of malignant pleural mesothelioma with endobronchial extension. Biopsy specimens were obtained through fibreoptic bronchoscopy and blind needle pleural biopsy. The final diagnosis was only possible after careful histological evaluation with a combination of immunohistochemical markers.