Abstract
A case of malignant pleural mesothelioma was presented and mesothelioma cells in the pleural fluid were examined histochemically and electron microscopically. Thickening of the left pleura with effusion of a 62-year-old house wife was pointed out by the chest x-ray at the mass survey for the pulmonary tuberculosis.
The pleural effusion had a plenty of mesothelioma cells, which occasionally formed clusters. These clusters consisted of about 5 to 70 malignant cells and formed “balls”. The mesothelioma cells had round central nucleus with granular chromatin and a few nucleoli at the center of the cytoplasm. The rich cytoplasm had a few vacuoles stained with Alcian blue and showed blister structure by the Giemsa staining. PAS-positive granules were seen in the cytoplasm of malignant mesothelioma cells.
The perinuclear cytoplasm was stained with keratin immunohistochemically which corresponded to the deposited area of intermediate filaments and mitochondria revealed by electron microscopy.
