유방암에서 Her-2/neu의 평가방법과 임상적 의미 = Evaluation and Clinical Significance of Her-2/neu in Breast Cancer

다국어 초록 (Multilingual Abstract)

Background and Objectives: In breast cancer, Her-2/neu amplification/overexpression predicts a poor clinical outcome and an enhanced survival benefit is rEported with the Her-2/neu targeted therapy. The purpose of this study was to establish a sensitive and specific method for Her-2/neu testing. We compared immunohistochemistry (IHC) detection of Her-2/neu overexpression with differential polymerase chain reaction (PCR) to assess gene amplification of Her-2/neu in breast carcinoma. Also we evaluated the prognostic values of Her-2/neu amplification/overexpression. Materials and Method: We have studied Her-2/neu amplification/ overexpression in 163 cases of invasive ductal carcinoma of breast using paraffin-embedded tissue. The evaluation of positivity for IHC was ≥10% moderate or strong complete membranous staining. Tumors were positive for gene amplification if the ratio of Her-2/neu gene to control gene was ≥2. Results: The overexpression of Her-2/neu was detected in 39 (23.9%) cases. The amplification of Her-2/neu was detected in 37 (22.7%) cases. Both methods were positive in 21.5% of cases and negative in 74.8% of cases. There was 96.3% concordance between the two methods. The sensitivity of IHC as compared with PCR was 94.6% and the specificity 96.8%. Positivity of Her-2/neu was significantly associated with node positivity and large tumor size. Conclusion: We conclude that automation of PCR-based Her-2/neu testing approaches is expected to play an increasing role in future for Her-2/neu testing. Also we have demonstrated that IHC is a sensitive and specific method for assessing Her-2/neu status in breast cancer when compared with PCR. Her-2/neu amplification or overexpression appears to be associated with a more aggressive phenotype.