There was a significant mean difference between adenomas (Mean PI = 30.97 ± 11.44) and adenocarcinomas (Mean PI = 46.33 ± 25.16) when compared with Ki-67 PI (%), with a p-value = 0.02 (< 0.05).  Conclusions: The Ki-67 immunohistochemical technique is a simple and reproducible technique. This evidence concerns the gene MKI67 and adenoma.