Clinical relevance of HER-2/neu overexpression in patients with testicular nonseminomatous germ cell tumor.

INTRODUCTION Recent scientific attention has focused on the role of growth factors in the progression of cancer. HER-2/neu is an epidermal growth factor receptor that is demonstrated to have correlation with poor prognosis of many cancers. This study evaluated the overexpression of HER-2/neu protein and its clinical importance in nonseminomatous germ cell tumors of the testis. MATERIALS AND METHODS Testis specimens of 54 patients with testicular nonseminomatous germ cell tumors, referred to Omid Hospital from 2001 to 2007, were re-evaluated and the patients' records were reviewed. Patients' age, tumor subtype, tumor stage, tumor markers, therapeutic response, and disease-free survival were assessed and the specimens were evaluated for the degree of HER-2/neu expression using an immunohistochemistry method. RESULTS Immunohistochemical staining was performed for 54 specimens. Overexpression of HER-2/neu was seen in 33.3% of the patients with nonseminomatous germ cell tumors, especially in those with teratocarcinoma subtype compared to those with mixed germ cell tumors or embryonal cell carcinoma. However, HER-2/neu overexpression did not show any correlation with tumor stage, therapeutic response, disease-free survival, age, beta-human chorionic gonadotropin, or alpha-fetoprotein. CONCLUSION We observed overexpression of HER-2/neu receptor in teratocarcinoma subtype of germ cell tumor. We suggest further studies to evaluate the clinical importance of this finding.