Wednesday, May 16, 2007 - Testing tissue surrounding breast tumors may be able to tell doctors as much about the cancer as the tumor itself. In a recent study, researchers identified eight genetic markers in the tissue surrounding breast tumors that appeared to influence the tumor's strength and whether the cancer would spread to the lymph nodes. They say the results need to be validated, but they hope to create a model doctors can use to interpret genetic changes in breast cancer tissue when a tumor is present.