Breast Cancer Index^SM

Know your risk of cancer recurrence

Accurately assessing the likelihood of your cancer returning provides essential information to guide your doctor’s treatment decisions. Breast cancer patients are typically classified as having a “high”, “intermediate” or “low” potential for recurrence, based on a number of factors. Traditionally, patients determined to have intermediate risk factors have presented unique treatment and decision-making challenges for physicians. It has been widely recognized that some “intermediate risk” patients who should have more accurately been classified as higher risk may have gone under-treated; other “intermediate risk” patients, who should have been classified as lower risk, may have been over-treated. Studies show that up to forty or fifty percent of breast cancer patients are inaccurately classified as “intermediate risk” according to St. Gallen’s risk assessment guidelines.

One important factor that physicians consider when evaluating recurrence risk is whether or not breast cancer cells are found in the lymph nodes close to the tumor. During surgery, lymph nodes are removed for analysis by a pathologist. If the lymph nodes show no signs of cancer, this often means a better prognosis for the patient than if multiple nodes are found to have cancer cells.

Another factor often considered is the “estrogen receptor” or ER status of a tumor. To determine presence of ER, special stains are used to detect estrogen receptor in the tumor cells. The presence of the estrogen receptor usually means that the tumor will be responsive to endocrine therapy.

Better classification means better treatment selection

Molecular testing through Breast Cancer Index refines risk assessment by grouping patients with ER-positive, lymph node-negative breast cancer into low, intermediate, or high-risk recurrence categories along with a continuous risk curve. This, in turn, enables physicians to objectively identify those patients who are in need of, and would most likely benefit from, endocrine therapy, and those whose tumors are likely to be sensitive or resistant to chemotherapy.

A more complete picture of prognostic information

The Breast Cancer Index is a combination of two molecular tests that independently evaluate distinct biological pathways – one pathway for endocrine signaling and one for analyzing proliferation, or tumor growth rate. A simultaneous assessment of the tests, expressed through the Breast Cancer Index, provides independent and complementary prognostic information useful for risk assessment and treatment decisions.