Malignant biphasic pleural mesothelioma metastatic to the liver diagnosed by fine-needle aspiration.

As malignant pleural mesotheliomas are most often rapidly fatal, distant metastases are rarely detected. Here, we report a unique case in which the diagnosis of metastatic pleural mesothelioma was made via cytologic examination of a fine-needle aspiration (FNA) of the liver. Recognition of the cytomorphologic features inherent to mesothelioma cells on FNA material may become important for proper patient management. To the best of our knowledge, the diagnosis of malignant pleural mesothelioma metastatic to the liver made by FNA has not been previously documented.