The SOFT results inspired Dr. Rugo to propose a new treatment algorithm for women with premenopausal hormone receptor–positive early-stage breast cancer. Patients who receive chemotherapy for high-risk disease – that is, women who are younger and especially those under age 35, with larger, grade 3 tumors, and/or node-positive disease – should subsequently undergo ovarian suppression combined with either exemestane or tamoxifen, with the choice being individualized based upon drug side effect profiles and tolerance. Those with low-risk disease not treated with adjuvant chemotherapy can be well treated with tamoxifen alone for at least 5 years.
The SOFT trial didn’t provide guidance regarding management of premenopausal women with intermediate-risk disease – those with low-grade but larger and/or node-positive tumors – but other evidence suggests ovarian suppression combined with exemestane or tamoxifen is a reasonable strategy there, too, said Dr. Rugo, professor of medicine at the University of California, San Francisco.
American Association for Cancer Research President Dr. Carlos L. Arteaga said he suspects a substantial number of premenopausal women who have undergone chemotherapy for high-risk hormone receptor–positive breast cancer and have embarked on a planned 10 years of adjuvant tamoxifen which they’re not looking forward to will be interested in the shorter SOFT alternative consisting of 5 years of exemestane plus ovarian suppression.
Simultaneous with Dr. Francis’ presentation in San Antonio, the SOFT results were published online in the New England Journal of Medicine (doi:10.1056/NEJMoa1412379).
The trial was conducted by the International Breast Cancer Study Group and funded by the National Cancer Institute and Pfizer. Dr. Francis reported having no financial conflicts.