1989 Volume 28 Issue 3 Pages 444-449
A case of malignant mesothelioma of the peritoneum is presented with its cytology, histopathology, immunohistochemistry, electron microscopy and cell kinetics using bromodeoxyuridine (BrdU).
A 50-year-old male was admitted to the Kochi medical school hospital because of ascites, and rt-cervical and ltinguinal tumors were also found. Abdominal CT scanning demonstrated thickened mesenterium and retroperitoneum. Cytology of peritoneal effusions and aspirates from these tumors revealed that numerous mesothelial cells with large papillary clusters contained multinucleated giant cells. A small numbers of intranuclear inclusions were also found. Histologically, biopsy specimens of these tumors were metastatic epithelial type of mesothelioma. Immunohistochemical staining with ABC method showed that the tumor cells were reacting positively for EMA, Vimentin and Keratin, however, negatively for CEA. Ultrastructural studies had demonstrated that the tumor cells had epithelial characteristics with numerous complex and elongated microvilli (MLDR=17-19). The percentage of BrdU positive mesothelioma cells was about 7% and it was higher than that of reactive mesothelial cells and macrophages obtained from other cases.
It is sometimes difficult for identified the malignant epithelial mesothelioma cells in effusion cytology. However, it is important to find the nature of mesothelioma cells with special stains for hyaluronic acid, immunohistochemistry and electron microscopy. The findings of intranuclear inclusions and detection of cell kinetics using BrdU method may be useful for distinction between reactive mesothelial cells and malignant epithelial mesothelioma cells.
