Abstract
Four cases of malignant mesothelioma (2 cases of epithelial type, 2 of mixed type) were examined and reviewed with literature regarding their cell morphology and staining features using cytological, surgical and autopsy materials.
In body fluids, tumor cells appeared isolated or in cell aggregates, showed round to oval cytoplasmic configuration, and the cytoplasm were stained bluish green by Papanicolaou's stain.
Occasional unstained cytoplasmic vacuoles were noted. Nuclei located eccentrically or centrally with prominent nucleoli which were stained dark red. PAS positive materials were noted in the cytoplasm of cases 1, 2, and 4 and were granularly, diffuse or lumpy in case 2. Alcian blue and colloidal iron stains were positive in the interstitium and in the cytoplasm of tumor cells in lineal fashon in the periphery and/or intracytoplasmic clump either in surgical and/or autopsy materials of all four cases.
These phenomena proved the existence of hyaluronic acid in the tumor, however there were differences in the shape of positive materials and the features against digestion with hyaluronidase.
In case 4, acid mucopolysaccharides (glycoseaminoglycan) were quantitated and showed the coexistence of hyaluronic acid and chondroitin sulfate in the tumor.
