A 64-year-old man who has worked in a manufacturing plant all his life complains of an 8-month history of chest discomfort, malaise, fever, night sweats, and weight loss. A chest X-ray reveals a pleural effusion and pleural mass encasing the lung. The patient subsequently dies of cardiorespiratory failure. Histologic examination of the pleural mass at autopsy shows a biphasic pattern of epithelial and sarcomatous elements. What is the most likely diagnosis?
Malignant mesothelioma. Mesothelioma is a malignant neoplasm of mesothelial cells that is most common in the pleura, but also occurs in the peritoneum, pericardium, and the tunica vaginalis of the testis. The tumor is strongly linked to occupational inhalation of asbestos. Patients are often first seen with a pleural effusion or a pleural mass, chest pain, and nonspecific symptoms, such as weight loss and malaise. Pleural mesotheliomas tend to spread locally and extensively within the chest cavity, but do not typically invade the pulmonary parenchyma. Wide-spread metastases can occur. Mesothelioma is typically composed of both epithelial and sarcomatous elements (i.e., biphasic pattern). The other choices do not ordinarily encase the lung.Diagnosis: Malignant mesothelioma
Carcinoid tumor
Large cell carcinoma
Malignant melanoma
Malignant mesothelioma
Respiration