Immunoreactivity for cadherins, HGF/SF, met, and erbB‐2 in pleural malignant mesotheliomas

Aims To assess the immunoreactivity of malignant mesotheliomas for N‐ and E‐cadherins, hepatocyte growth factor/scatter factor (HGF/SF) and the tyrosine kinase receptors, met and erbB‐2. Methods and results Pleural malignant mesotheliomas were stained using a standard indirect immunoperoxidase method applied to paraffin sections. Malignant mesotheliomas were immunoreactive for N‐cadherin (26/29; 90%), met (29/29; 100%) and erbB‐2 (28/29; 97%). Focal immunoreactivity was present for E‐cadherin in epithelioid or mixed tumours (14/25; 56%), and for HGF/SF (9/24; 38%). Conclusions Expression of N‐cadherin supports the diagnosis of malignant mesothelioma and use of appropriate antibodies would be a useful addition to a diagnostic antibody panel. Focal staining for E‐cadherin does not exclude mesothelioma. Signalling pathways mediated via met and erbB‐2 may play a role in the growth and spread of malignant mesotheliomas.