The Oncotype DX test is a valuable tool for women trying to make one of breast cancer’s most difficult decisions: Would undergoing chemotherapy be worth the ordeal, or not? By assessing gene activity in 21 different genes extracted from a woman’s tumor, the Oncotype test can determine how likely a woman’s cancer is to recur. The higher the likelihood of recurrence, the more sense it makes to go through chemo.
Now a new test, the Breast Cancer Index (BCI), is working its way into oncologists’ offices — and it’s likely to have just as great an impact on the breast cancer community as the Oncotype DX. Like Oncotype, the BCI measures gene activity; but it measures different genes, and instead of predicting how likely a quick recurrence might be, it predicts recurrence ranging from five to 10 years after diagnosis (known as late recurrence).
Why is this helpful? Because women with hormone-positive, early-stage breast cancer taking hormone therapy drugs (e.g., tamoxifen, aromatase inhibitors) are often faced with decisions as tough as those around chemo: Are the side effects worth the protection?
According to the National Cancer Institute, serious side effects can include an increased risk of secondary cancers, bone loss, stroke, heart attack, and blood clots. Less serious side effects range from depression and loss of libido to joint pain and mood swings.
The BCI helps clarify a survivor’s hormone therapy decision by offering guidance around how likely therapy is to prevent recurrence five years down the road. BCI also helps women decide whether to extend therapy, from the standard five years to 10 years — an option increasingly recommended for consideration by oncologists, as 10-year data starts to accumulate.
I had the opportunity to interview Tara Sanft, M.D., medical director of the Yale Cancer Center’s survivorship clinic. Dr. Sanft headed up a study examining the effect of the BCI on doctor recommendations and patient decisions around hormone therapy. We'll share the video soon. It provides information useful to women making decisions around hormone therapy — whether to have it, and for how long.
See more helpful articles:
Oncotype DX Can Help Predict Chances of Breast Cancer Recurrence
Understanding Hormone Therapy Drugs
Aromatase Inhibitor FAQS
Hormone Therapy: Understanding Tamoxifen