Background: Malignant pleural mesothelioma (MPM) in Egypt is mainly attributed to an environmental origin i.e exposure to asbestos, with a high incidence in women and young adults. Immunohistochemistry and ultrastructural features aid in the diagnosis. The p27Kip1 is a kinase inhibitor protein acting as a cell cycle regulator and a putative tumor suppressor gene playing a critical role in the pathogenesis of several human neoplasms.
Aim: A clinicopathologic, immunohistochemical and ultrastructural study of mesothelioma in Egyptian patients, with identification of different prognostic factors.
Material and methods: Sixty-one cases of MPM were collected from the department of pathology at the NCI, Cairo. Cases were stained by monoclonal antibodies against CK5/6, calretinin, vimentin, CD15, CEA and p27.
Results: More than half (57.4%) of the patients were residents in endemic areas; 50.8% were of epithelioid type. CK5/6 was positive in 45 (73.8%) cases, 39 (63.9%) cases were positive for vimentin, 49 (80.3%) cases were positive for calretinin. One case showed a focal weak positive reaction to CD15. None of the cases stained for CEA. There was a statistically significant relation between p27 expression and the histopathologic type (p=0.02) between overall survival and age (p=0.01), histopathologic type (p=0.02) and stage (p=0.006).
Conclusion: MPM is an increasing disaster in Egypt which is underestimated and neglected. A panel of immunohistochemical markers should be used for proper evaluation. p27 has proven to be a potential biologic prognostic marker for mesothelioma and more studies as regard its significance are recommended on a larger number.