Quantitative measurement of HER2/neu oncogene amplification and p53 tumor suppressor gene deletion by RT-PCR in breast cancer

Objective: The aim of the study was to quantitatively evaluate HER2/neu oncogene amplification and p53 tumor suppressor gene deletion in breast cancer with real-time polymerase chain reaction (RT-PCR). Materials and Methods: Sections obtained from the tumor tissues of 50 patients were paraffinized on slides, and DNA extraction was performed. HER2/neu amplification and p53 deletion were analyzed using RT-PCR with respect to immunohistochemistry (IHC). Results: For 25 patients with breast cancer, we compared IHC and RT-PCR results for the quantitative measurement of HER2/neu expression. We found a significant correlation between the results obtained using IHC and RT-PCR (p < 0.05). Taking the results of IHC as reference, the sensitivity and specificity of the RT-PCR method were 57% and 83%, respectively. HER2/neu amplification and p53 deletion did not have a significant correlation with tumor size, histological grade, lymph node invasion, and status of estrogen receptor and progesterone receptor (p>0.05, for all). Conclusion: RT-PCR measured gene levels reliably and accurately with high sensitivity and specificity, making it superior to IHC, which is subjective.