Genomic testing is much more specific than genetic testing
Unlike normal genetic testing, genomic testing looks at the genes expressed in the tumor itself. Since cancer involves damage at the genetic level, the tumor will have different genes from the rest of the body.
Genomic testing not only looks at the gene sequence in the tumor itself but also looks at how they are interacting with other genes in nearby healthy cells in order to get a larger picture of the danger expressed by the cancer.
The genomic score will be determined by using Oncotype DX. Oncotype DX tests for 21 genetic mutations in breast cancer. The same company also has tests designed to be used with colon cancer and prostate cancer.