Conclusion
ErbB2/HER2 is generally upregulated in human meningiomas, but in an activated state only in a few cases. Only the activated receptor is associated with poorer prognosis, a link that needs further investigations.
Methods
In total, 186 human meningiomas of all malignancy grades were included in the study, 163 of these were in tissue microarrays (TMA). Antibody expression was assessed by means of immunohistochemistry (IHC) and gene amplification by fluorescence in situ hybridization (FISH).
Results
All cases were immunoreactive with antibodies targeting the intracellular domain, whereas about 48% and 11% were positive with antibodies against the extracellular domain and against the activated receptor, respectively. Normal meninges were not immunoreactive. There were no relations to malignancy grade, and only the activated receptor was significantly correlated with increased risk for recurrence or death (time to recurrence: HR 1.568, CI (1.153 to 2.132), p = 0.004). No gene amplification was found.