Figure 14a. Malignant mesothelioma in a 56-year-old man. (a) CT scan obtained at the level of the left atrium shows a 4-mm-diameter lymph node in the left extrapleural space (arrow). (b) CT scan obtained at the level of the clavicles shows a 2-cm-diameter left supraclavicular node (arrow), which was confirmed to be metastatic. This finding is defined as N3 disease. (c) CT scan obtained at the level of the interventricular septum shows a cluster of enhancing left peridiaphragmatic nodes (arrow). Note the irregular, enhancing, nodular pleural thickening and the loculated pleural effusion.