Genomic Health Inc.'s genetic test for breast cancer kept doctors from recommending unnecessary chemotherapy when a patient's DNA profile showed they were at a lower risk of disease recurrence, a study found.
In a study of 89 women, doctors recommended a different treatment 31.5 percent of the time after the test, which examines 21 genes tied to tumor growth, helped determine a women's specific risk of relapse. Twenty of the women determined to have a low or intermediate risk of recurrence were advised they could skip chemotherapy.
The results are the first to show doctors have gained enough confidence in the test, introduced in January 2004, to change their habits. The data may encourage more insurers to pay for the $3,460 test, particularly if cancer patients can avoid chemotherapy that can cost $15,000 or more, the company said.
"This is a very important new dimension to the idea of tailoring treatment," said Kathy Albain, a breast cancer specialist at Loyola University Medical Center in Maywood, Illinois, and an author of the study. "We already knew we could do this. Now we know we're really making a difference."
The study, presented at the American Society of Clinical Oncology in Chicago, didn't follow patients after they chose their therapy to see if they did any better, said Steven Shak, Chief Medical Officer of the Redwood City, California- based company, in a telephone interview. Other studies are under way to answer that question, Shak said.