Positive results from Genomic Health's Oncotype DX study in breast cancer patients with node-positive disease

Dec 11 2009

Genomic Health, Inc. (Nasdaq: GHDX) today announced that The Lancet Oncology published positive results from a study of Oncotype DX(®) in postmenopausal women with node-positive, estrogen receptor-positive breast cancer conducted by the Southwest Oncology Group (SWOG), a National Cancer Institute-supported clinical trials cooperative group. The Lancet Oncology published these results online as an "early release" to coincide with additional data analyses reinforcing that the Oncotype DX breast cancer test can help predict chemotherapy benefit in breast cancer patients with node-positive disease. These data, presented today as a late-breaking poster during a discussion on multigene assays at the 32nd Annual CTRC-AACR San Antonio Breast Cancer Symposium (Abstract #112), support the clinical utility of Oncotype DX in this patient population.

The study published in The Lancet Oncology challenges the current treatment standard of adjuvant chemotherapy for all women with lymph node-positive breast cancer.

"These studies indicate that the Oncotype DX Recurrence Score(®) result can provide beneficial clinical information beyond standard pathology testing for node-positive breast cancer patients," said Kathy S. Albain M.D., Professor of Medicine, Division of Hematology/Oncology, Department of Medicine, Loyola University Chicago Stritch School of Medicine, Cardinal Bernardin Cancer Center, Loyola University Health System, Maywood, Il, and senior author of the study. "With the right chemotherapy regimen, we can favorably impact survival; but it is also important to avoid the toxicity and medical costs of chemotherapy when it may not be needed for patients whose tumors have a distinct biology not responsive to standard chemotherapy."

For the study published in The Lancet Oncology, researchers analyzed 367 tumor samples from node-positive, estrogen receptor-positive breast cancer patients who participated in the SWOG/Breast Cancer Intergroup of North America trial that evaluated CAF chemotherapy followed by tamoxifen versus tamoxifen-alone, to determine the prognostic and predictive effects of the Oncotype DX Recurrence Score.

The Recurrence Score was highly prognostic in the tamoxifen-alone arm>

"Since these data were originally presented in 2007, I have used Oncotype DX to help make treatment recommendations for select node-positive patients in my clinical practice," said Eric Winer, M.D., Chief, Division of Women's Cancers at Dana-Farber Cancer Institute and Professor of Medicine at Harvard Medical School. "It is imperative that we bring our new molecular insights into clinical practice so that we can optimize and individualize treatment for every patient with breast cancer."

Additional data analyses presented at the CTRC-AACR San Antonio Breast Cancer Symposium today reinforced the conclusion that chemotherapy does not appear to benefit patients with either 1-3 or 4 or more positive nodes for disease-free survival over 10 years, if their tumors have a low Recurrence Score. There was no breast cancer specific survival (BCSS) benefit from chemotherapy in either the low (log-rank>

"There are now five studies involving more than 1,000 patients that support the clinical utility of Oncotype DX in guiding treatment selection for node-positive breast cancer," said Steven Shak, M.D., Chief Medical Officer, Genomic Health. "With this suite of clinical evidence, recently expanded Medicare coverage and clinical experience with more than 5,500 patients with node-positive breast cancer, we believe we can arm node-positive patients and their physicians with the same accurate, standardized genomic information that node-negative patients and their doctors have been using to help guide treatment plans over the past five years."

A separate study analyzing how the Oncotype DX Recurrence Score impacts treatment recommendations in breast cancer patients with node-positive disease (Abstract #2031) will be presented at the San Antonio Breast Cancer Symposium on Friday, December 11, 2009 at 7a.m. CST.