Dr. O'Regan Discusses Breast Cancer Index in HER2-Positive/HR-Positive Patients

Ruth O'Regan, MD, medical oncology, Breast Cancer Clinic, University of Wisconsin Carbone Cancer Center, faculty, University of Wisconsin School of Medicine and Public Health, evaluates the Breast Cancer Index in patients with HER2-positive, HR-positive breast cancer for risk of late recurrence and endocrine benefit.

The Breast Cancer Index is a molecular profiling assay that has been used to measure the benefit of endocrine therapy for patients with ER-positive breast cancer. Currently, it’s mainly used to determine which patients require more than 5 years of endocrine therapy, O’Regan says.

A recent study focused on evaluating the Breast Cancer Index in patients with HER2-positive, HR-positive breast cancer. Data showed that the majority of these patients are at a high risk of recurrence. Also, the use of endocrine therapy for more than 5 years was found to be effective in two-thirds of these patients.

It is also suggested that these patients may benefit from extended adjuvant therapy compared with patients who are HER2-negative. These findings could be practice-changing, O’Regan explains.