Malignant Pleural Mesothelioma with Marked Lymphatic Involvement: A Report of Two Autopsy Cases
(a) An axial high-resolution chest CT scan showed extensive bronchovascular bundle and septal thickening and a consolidative mass in the upper lobe of the right lung; these findings are consistent with the lymphangitic spread of the tumor. (b) The gross pathological findings of the lung and pleura at autopsy showing multiple pleural nodules and masses on the pleural surface. The lung parenchyma is encased by tumor growth and the lymphatic spread of the tumor is observed. (c) Light microscopy of the resected pleural tumor. The lesion was histologically diagnosed as epithelioid-type malignant pleural mesothelioma. The marked invasion of the lymphatic vessel by tumor cells was observed (hematoxylin and eosin staining, ×100). (d) On immunohistochemical staining, the tumor cells were positive for calretinin, a mesothelial cell marker.