The findings were shared at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting, held recently in Chicago, in a presentation titled, “Trans-aTTom: Breast Cancer Index for prediction of endocrine benefit and late distant recurrence (DR) in patients with HR+ breast cancer treated in the adjuvant tamoxifen—To offer more? (aTTom) trial.”
Endocrine therapy starves tumors of the hormones, primarily estrogen, that drive cancer cell growth. For people with hormone receptor (HR)-positive breast cancer, it can be lifesaving. However, endocrine therapy also can cause a number of unpleasant side effects, including osteoporosis, joint pain, blood clots, and endometrial cancer.
This has led to a dilemma over how long endocrine therapy should be given — for five or 10 years?
The Breast Cancer Index (BCI), a test that measures gene expression in the tumor, is intended to solve this problem by identifying those patients who will benefit from the additional five years of treatment. That would allow clini