Not everything is what it seems: malignant pleural mesothelioma mimicking lung cancer

Malignant pleural mesothelioma usually arises from the pleural surface and progressively encases the lungs. Pulmonary involvement generally occurs at an advanced stage, while intraparenchymal nodules, in the absence of pleural lesions, constitute a less frequent presentation. We describe the case of a patient with multiple bilateral pulmonary nodules, mediastinal lymphadenopathies and left pleural effusion in the absence of pleural lesions, simulating advanced stage lung cancer. Thoracoscopic inspection did not detect any lesions. Pathological examination on one pulmonary nodule revealed malignant pleural mesothelioma. Despite its rarity, intraparenchymal malignant pleural mesothelioma should always be taken into account, when lung nodules are present, to prevent misdiagnosis and avoid delayed treatment.