Gene Tests Can Help Some Breast Cancer Patients Avoid Chemotherapy, Study Says

LOS ANGELES (CBSLA.com) — Some breast cancer patients could avoid chemotherapy treatment without jeopardizing their chances of survival by taking a genetic test to determine the risk of their cancer recurring, a study has found.

The study, published in the New England Journal of Medicine, examined early-stage breast cancer patients using MammaPrint, a 70-gene test that creates something of a cancer "fingerprint" and categorizes patients as high risk or low risk based on genetic factors.

Patients can use that genetic information to inform their treatment choices, and doctors can use it avoid recommending chemotherapy to patients who would not necessarily benefit from it.

Nicki Durlester of Sherman Oaks, who was diagnosed with breast cancer in 2009, participated in the study and was deemed low risk by MammaPrint. She chose to forgo chemotherapy.

"Human nature is to throw everything but the kitchen sink at cancer," she said. "I guess my gut and due diligence really helped me to make the final decision."

The study examined a total of about 6,700 patients with early-stage breast cancer. Of those, about 1,500 women were considered "low risk" by MammaPrint based on genetic factors.

Those low risk patients were then divided into two groups -- one received chemotherapy treatment, and the other did not. After five years, the survival rate of the two groups was similar, researchers said -- though about 1.5 percent higher for the group receiving chemotherapy. The survival rate for the group that did not receive chemotherapy was about 95 percent.

The study found that 46 percent of patients who under ordinary examination would be deemed "high risk" were deemed "low risk" by MammaPrint, and could choose to forgo chemotherapy.

Durlester's doctor, Dr. Kristi Funk of the Pink Lotus Breast Center in Beverly Hills, said the results were extraordinary and could pave the way for many breast cancer patients to forgo chemotherapy treatment without risking their lives.

"This is a game changer for women all around the world," Funk said. "(Many) women in the US who would be told to have chemo aren't benefiting from it. That's huge."