To determine whether the TOP2A expression evident in gastric adenocarcinomas was a result of gene amplification or chromosome 17 polysomy, we established three cut-off points for TOP2A NI values at 5%, 10%, and 25%, and tried to identify the statistical difference in the prescence of TOP2A amplification or chromosome 17 polysomy with a cut-off less than 5%(or10%,25%) vs 5% (or10%,25%)or more. Here, TOP2A is linked to gastric adenocarcinoma.