1987 Volume 26 Issue 3 Pages 476-481
Two cases of diffuse epithelial malignant mesothelioma were reported cytologically and histologically.
Case 1 was 75-year-old man with peritoneal papillary mesothelioma and case 2 was 79-year-old man with left pleural papillo-tubular mesothelioma.These two cases showed cytologically similar findings as described below.
The tumor cells were medium-large cells with 20-50 μm in diameter. Numerous free large round tumor cells together with clusters were recognized.The cytoplasm of these tumor cells were deeply stained with light-green but pale in peripheral marginal zones circumferentialy as though ring-like fashion.These pale areas, in the other hand, were positively stained diffusely and/or granulary with PAS reaction and were disappeared by the pretreatment of diastase. These findings were considered to be the key points to diagnose as the tumor cells were derived from mesothelium. Therefore, the two cases were finally diagnosed cytologically as epithelial malignant mesotheliomas.
It may be possible to diagnose cytologically in the case of epithelial type of malignant mesothelioma, by means of the recognition of differentiated mesothelioma cells with both mesothelial characteristics and the criteria of the malignancy.
