A new gene test for patients with breast cancer – MammaPrint – could dramatically reduce the number of women who need chemotherapy.
Available in Lincoln at Bryan Health and Saint Elizabeth Regional Medical Center and in Omaha at University of Nebraska Medical Center and Nebraska Medical Center, the test analyzes 70 key genes and helps determine which patients are at low risk of breast cancer recurrence and could safely choose not to have chemotherapy.
The test has been validated in a peer-reviewed study called Microarray Prognostics in Breast Cancer, or RASTER, conducted in 16 community-based clinics in the Netherlands. The results were published online earlier this year in the The International Journal of Cancer and will later appear in the journal’s print edition.
In the five-year study, 427 breast cancer patients took the MammaPrint test and 219 of them were determined to be low risk and 208 high risk.
Of the low-risk patients, 85 percent chose not to have chemotherapy. Of them, 97 percent were disease-free after five years.
Of the 208 high-risk patients, 81 percent chose chemotherapy and 91 percent were disease-free after five years.
“This is an important breakthrough for breast cancer patients,” Dr. James Edney, UNMC professor of surgical oncology said in a statement released by UNMC. “By incorporating MammaPrint results along with the traditional clinical parameters, such as tumor size, grade, patient age and lymph node status, we can significantly reduce the number of women who need chemotherapy. In doing so, they can avoid the side effects and toxicity of chemotherapy treatment, some of which can be permanent and debilitating.”
Long-term side effects of chemotherapy could include damage to the heart, kidneys, lungs, nerves or reproductive organs. There is also the chance of developing a second cancer as a result of it, said Edney, who has used the test on about 160 patients.
Response, he said, has been extremely positive.
Lincoln doctors who have used MammaPrint declined to comment, saying the test was too new for them to have a public opinion.
Unlike other breast cancer genomic tests that are limited to patients with such disease characteristics as certain receptor and lymph node status, Edney said MammaPrint can be given to all early-stage breast cancer patients via a breast cancer assay on either fresh or fixed tumor tissue.
MammaPrint results benefit the physician, he said, by clearly categorizing all patients as high or low risk and eliminating the uncertainty of indeterminate scores reported by other genomic test methods.
The RASTER study is the first and only to prospectively evaluate the performance of a genomic breast cancer test by using outcome data, Edney said. In this case, patients were followed for five years.
The study showed that MammaPrint identified 30 percent more patients as low risk than traditional clinical parameters used in the U.S. to determine risk of recurrence. The test has been cleared by the U.S. Food and Drug Administration.
MammaPrint was developed by Agendia, a molecular diagnostic company headquartered in Amsterdam with a genomics laboratory in Irvine, Calif.