Women with early stage breast cancer now have a new tool at their disposal. The tool -- called MammaPrint -- is newly approved by the FDA and while it is not yet a perfect measure, it can be used along with other information to estimate whether breast cancer is likely to return in five or 10 years.The value of this test, that measures through computer analysis the activity of 70 genes using a sample of tissue removed from a breast tumor, is that doctors and patients can better determine course of treatments.
MammoPrint offers two results -- high risk and low risk -- and accurately picked in studies which women were at low risk at least 90 percent of the time. However, for women who were told they were at high risk for recurrence as a result of the test, just 23 percent experienced a relapse.
"You can't go all the way to the bank with this test," says FDA official Dr. Steven Gutman who argues the test is still better than having no information at all.
Agendia, the Dutch maker of MammoPrint, is exploring ways to make this one-of-a-kind product available in the United States. It has been used in the Netherlands since 2005.
"This test has enormous implications for the short-term future of cancer research in general, and is one of the truly great breakthroughs of our time," says Cancer Blog reader Gregory Pawelski with whom I am grateful for sharing this story tip with me.
1. Another new test, that looks at the expression of 70 genes linked to breast cancer, can accurately assess a patient's risk of recurrence or death. The correlations of this are vastly superior to those obtained with standard prognostic markers.
The 70 genes in a woman's tumor analyzed by MammaPrint predict the 10-year survival of the patient at a significance level over three times greater than existing methods and with an accuracy level of 96.7% as determined by a study published in the New England Journal of Medicine.
Existing methods can't distinguish the patients with a high risk for recurrence from those with low risk with comparable accuracy. This new gene expression profiling test enables the oncologist and breast surgeon to more accurately determine who should be treated.
This test, and three other multi-gene tests have been shown to be superior over conventional assessment of risk of future metastatic disease, such as histological assessment of tumor aggressiveness (by grade). One gets more accurate information when using intact RNA isolated from "fresh" tissue than from using degraded RNA, which is present in paraffin-fixed tissues.
This DNA microarray will prove to be highly complementary to the parellel breakthrough efforts in targeted therapy through cell culture tests like the EGFRx™ Assay.
Posted at 10:33AM on Feb 7th 2007 by Gregory D. Pawelski