A new prospective study shows a 21-gene test of a patient's breast cancer tumor may change doctor and patient treatment decisions, including the need for chemotherapy.
Researchers at Loyola University Health System, Maywood, Ill., presented the findings at the American Society of Clinical Oncology annual meeting.
Participating in the study were 89 patients with early-stage, node-negative, estrogen-receptor-positive breast cancer and 17 medical oncologists at four different centers nationally. Each patient had the multi-gene expression test taken from a tissue sample of the tumor, which produces a very specific, molecular fingerprint of the cancer.
The Oncotype DX(tm) Recurrence Score(tm) tells the chance of distant recurrence of the cancer over 10 years if only tamoxifen is given and provides the likelihood of benefit from chemotherapy. Treatment decisions are based on whether the score is low, medium or high. Participating physicians and patients were surveyed regarding their treatment decision before the test was sent and again after discussion of the test results.
"This test score changed the treatment decisions of 31.5 percent of medical oncologists and 27 percent of patients," said senior study investigator Dr. Kathy S. Albain, director, breast clinical research program; and co-director, the multidisciplinary breast oncology center at the Cardinal Bernardin Cancer Center, Loyola University Health System, Maywood, Ill.
"It's a new dimension of tailoring treatment to the individual," said Albain, professor, division of hematology/oncology, department of medicine, Loyola University Chicago Stritch School of Medicine, Maywood.
"The study proves for the first time that the score impacts our decision-making as oncologists. "Test results reduced the number of women who had to undergo chemotherapy," said Albain.
In 22.5 percent of the cases, the doctors said the patient could avoid chemotherapy. In 76 percent of the cases, oncologists indicated they had increased confidence in their treatment decisions after reviewing the test results with their patients.
The majority of patients, 83 percent, reported that this test influenced their treatment decisions.
"The test score provides patients with more certainty that they are taking the right steps for their specific cancer," said Albain, also director of Loyola's thoracic oncology program.
Colleen G., 40, of Naperville, Ill., was relieved that her test results showed chemotherapy was probably not necessary. Diagnosed with breast cancer at 39, she would ordinarily undergo lumpectomy followed by radiation, chemotherapy and tamoxifen, based on her young age.
"My test results showed that the breast cancer is not as likely to recur, so I felt comfortable opting not to have chemo," said Colleen, a mother of two children. "That gave me peace of mind and confidence in my decision."
Colleen has had two mammograms since her treatment as well as close examinations and follow-up. Today, she remains a cancer-survivor, free of recurrence in the breast or elsewhere in her body.
The majority of the patients studied reported they were glad to have the opportunity to take the test. It must be ordered by a physician.
This investigator-initiated study was funded by an unrestricted grant from Genomic Health, Inc.
Co-authors of the study, with Albain, are lead investigator Dr. Shelly S. Lo,John Norton and Patricia B. Mumby, Ph.d., from Loyola; Dr. Jeffrey Smerage and Dr. Daniel Hayes from University of Michigan, Ann Arbor; Dr. Joseph Kash, Edward Hospital, Naperville, Ill.; Dr. Helen K. Chew, University of California- Davis, Sacramento; and Dr. Andrew Epstein, Mount Sinai Medical Center, New York.
Visit www.LoyolaMedicine.org for more information. To make an appointment with Albain, call (888) LUHS-888.