"The implications of tumor evolution over the course of treatment are significant," said Dr. Debasish Tripathy, professor of internal medicine and contributing author. "A better understanding of this process will not only allow us to use available drugs in a more individualized fashion but also may point to new therapeutic approaches." Dr. Tripathy heads the Komen/UT Southwestern Breast Cancer Research Program.

The next step is to evaluate patients whose circulating tumor cells have acquired HER-2 gene amplification to determine if these cells are reflecting the genetic status of the recurrent tumor, said Dr. Uhr. For the blood test to be considered worthwhile, research also must show that therapy with Herceptin alone or in addition to a chemotherapeutic agent can cause remissions in a significant number of patients.

Other UT Southwestern contributors to the PNAS study were Dr. Raheela Ashfaq, professor of pathology; Dr. Eugene Frenkel, professor of internal medicine; Dr. Marilyn Leitch, professor of surgical oncology; Dr. David Euhus, associate professor of surgical oncology; Dr. Barbara Haley, associate professor of internal medicine; Dr. Cynthia Osborne, assistant professor of internal medicine; Dr. Susan Hoover, assistant professor of surgical oncology; Dr. Edward Clifford, clinical assistant professor of surgery; and in the Cancer Immunobiology Center, Dr. Ellen Vitetta, director; Dr. Songdong Meng, postdoctoral researcher; Dr. Jianqiang Wang, postdoctoral researcher; Thomas Tucker, senior research scientist; and Nancy Lane, research scientist.

Researchers from UT M.D. Anderson Cancer Center; Texas Oncology PA; Dallas Surgical Group; Cancer Center Associates in Dallas; Vysis, Inc.; Wistar Institute; Immunicon Corp.; the Washington University School of Medicine in St. Louis; and Germany's University of Tubingen also contributed.

Research was supported by the Raymond D. Nasher Cancer Research Program and the Komen/UT Southwestern Breast Cancer Research Program.

utsouthwestern