Expression of c-met in malignant pleural mesothelioma: an immunohistochemical study

ABSTRACT

Most patients with malignant pleural mesothelioma present in advanced stages of disease. Response rates and survival with currently available therapies are poor. Therefore, it is critical to identify the molecular markers of mesothelioma which would provide a way of understanding this neoplasm and targeting these markers in therapy. To assess the immunoreactivity of c-Met in malignant pleural mesothelioma and to analyze the potential link of the c-MET expression to some clincopathological parameters such as tumor subtype, TNM stage and patients' survival. A total of 20 patients [7 females and 13 males] with pathologically confirmed MPM; age range, [35 to 63 years] were included in the study. The patient records for the clinical, radiological and laboratory investigations and the results of closed pleura biopsies were analyzed. Pleura biopsies were stained for c-Met using immunohistochemical technique applied to paraffin sections. Of the studied tumors 18 [90%] were immunoreactive for c-Met. There were no significant relations between c-Met and patient age [p=0.569] or gender [0.755]. Also there was no relation between c-Met expression and clinical symptoms. All tumors that showed distant metastasis were c-Met positive. While all c-Met negative tumors showed no metastasis. However, the difference was statistically insignificant. There was also no relation between c-Met and tumor subtype [p=0.40] or tumor stage [p=0.257]. However, all T3 and T4 tumors were c-Met positive and the two c-Met negative tumors were T[2]. The 2 c-Met negative patients showed one-year survival. Whereas [7/18] of patients with positive c-Met died. However, again the difference was statistically insignificant [p=0.755]. c-Met receptor was expressed in a high proportion of MPM. It may have a significant role in the development of MPM and could be a beneficial target for therapy. Though there was no statistically significant relation between c-Met expression and one-year survival or with different prognostic factors in MPM, we observed more c-met expression in more extensive cases and more deaths in c-Met positive cases. Additional larger-scale studies of MPM are needed to confirm the prognostic role of c-Met expression