By analysing the percentage-wise prevalence of HER2 overexpression in lung adenocarcinoma in studies that used HercepTest Dako and studies that used Ventana anti-HER2/neu (4B5) antibodies, we observed a higher prevalence when using Hercep Test Dako as compared to Ventana anti-HER2/neu (4B5) antibodies, which is also the case in our study [6,20,22,23,24,25]. This evidence concerns the gene ERBB2 and lung adenocarcinoma.