Test Determines Risk of Breast Cancer Returning
FDA has cleared for marketing a test that determines the likelihood of cancer returning within 5 to 10 years after a woman's initial breast cancer. It is the first cleared molecular test that profiles genetic activity.
The MammaPrint test, cleared in February 2007, uses the latest in molecular technology to predict whether existing cancer will spread to other parts of the body (metastasize). The test relies on microarray analysis, a powerful tool for studying the patterns of behavior of large numbers of genes in biological samples.
The recurrence of cancer partly depends on the activity of certain genes located in a tumor. Predictive tests like the MammaPrint can measure the activity of these genes to help physicians understand their patients' odds that the cancer will spread.
Agendia, the Amsterdam, Netherlands developer of MammaPrint, identified a set of 70 genes whose activity gives information about the likelihood that a tumor will recur. The MammaPrint test measures the level of activity of each of these genes in a sample of a woman's surgically removed breast cancer tumor. The test then uses a specific formula to produce a score that determines whether the woman has a low risk or high risk for the spread of the cancer to another place in the body. The result, when used with other clinical information and laboratory tests, may help a doctor plan appropriate follow-up for a patient.
Prior to clearing the test, FDA asked the developer for evidence that the MammaPrint had been properly validated for its intended use. Agendia submitted data from a study using tumor samples and clinical data from 302 patients at 5 European centers. The study confirmed that the test was useful in predicting the time until tumors developed in other parts of the body in women who:
- are under age 61
- are in the two earliest stages of cancer (Stage I and Stage II)
- have tumor size equal to or less than five centimeters
- have no evidence that the cancer has spread to nearby lymph nodes (lymph node negative)
According to the American Cancer Society, an estimated 178,480 new cases of invasive breast cancer will be diagnosed among women in the United States this year and over 40,000 women are expected to die from the disease.
This article appears on FDA's Consumer Update page, which features the latest on all FDA-regulated products.
Date Posted: May 14, 2007