Clinical Relevance of HER-2/neu Expression in Germ-cell Testicular Tumors

Abstract

Background: Amplification and/or overexpression of HER-2/neu are associated with poor clinical outcome in several epithelial tumors. However, the exact prognostic role of HER-2/neu expression in testicular germ-cell tumors is equivocal. Patients and Methods: Since teratomas are relatively chemoresistant tumors, we evaluated the HER-2/neu alterations of 59 primary testicular teratomas and mixed germ-cell tumors containing teratomatous components using the standardized immunohistochemical method (IHC) (HercepTest) and Fluorescence in Situ Hybridization (FISH). Results: HER-2/neu overexpression was detected in 14 (24%) out of 59 specimens. With IHC, teratomatous and choriocarcinoma components showed significantly higher HER-2/neu expression compared to other histological subtypes of GCTs (p=0.0095). A statistically significant correlation (p=0.0004) can be established between HER-2/neu status and clinical stage of the disease. Similarly, a significant correlation was observed between HER-2/neu overexpression and clinical outcome (p=0.0077). None of the specimens had definite HER-2/neu gene amplification. Conclusion: Our results suggest that HER-2/neu overexpression is associated with an adverse clinical outcome and has a prognostic role in testicular germ-cell tumors. Further studies are needed to evaluate the exact background of HER-2/neu overexpression in germ-cell tumors and the role of anti-HER-2/neu antibodies in the treatment regimens for this malignancy.