Eric P. Winer, MD, FASCO

Eric P. Winer, MD, FASCO, Thompson Chair in Breast Cancer Research and Professor of Medicine, Harvard Medical School, and Director of the Breast Cancer Program at Dana-Farber Cancer Institute, Boston, commented on Dr. Sparano’s presentation for The ASCO Post. “We already use information in addition to the recurrence score—such as clinical parameters—to estimate a woman’s risk of recurrence,” he said. “In my view, the single most important finding from this analysis of TAILORx is that in very young women (40 and under) and in postmenopausal women, there seems to be no benefit for adding chemotherapy in those with a recurrence score up to 25,” he said.

“This finding suggests that the benefit from chemotherapy for women aged 40 to 50 may be arising from an endocrine effect, because it is women in this age group who tend to go through premature ovarian failure. This means the treatment effect we are seeing may not be a direct effect of the chemotherapy, but an indirect effect as a result of premature menopause.”

Sandra M. Swain, MD, FACP, FASCO, Associate Dean for Research Development at Georgetown University Medical Center and the Lombardi Comprehensive Cancer Center, Washington, DC, said the main takeaway message to her was that subgroups of premenopausal patients with an intermediate recurrence score from 16 to 25 may still need chemotherapy. This is based on the integrated clinical and genomic risks.

Sandra M. Swain, MD, FACP, FASCO

“The NSABP B-30 study showed that patients with estrogen receptor– positive tumors who achieved ovarian suppression by chemotherapy had decreased recurrence. So it may be the endocrine treatment effect we are seeing in this study,” she continued.

“You can make the case for considering ovarian suppression and tamoxifen or an aromatase inhibitor instead of chemotherapy (as Dr. Sparano mentioned), but the problem is, we do not have prospective randomized data to support this hypothesis, though studies have been attempted. A direct cytotoxic effect from chemotherapy may still be needed,” she noted.

As for using clinical risk factors as an accompaniment to the 21-gene recurrence score, Dr. Swain commented, “That’s what we should do, and it’s what most clinicians have been doing. For those with higher recurrence scores (21–25), even if they have low clinical risk, we still give chemotherapy, and the study results support this in women aged 41 to 50. And for those with lower recurrence scores (16–20) but high clinical risk, we give many of them chemotherapy also.” ■

DISCLOSURE: Dr. Winer has held consulting roles and/or received honoraria from Carrick Therapeutics, Genentech/Roche, Genomic Health, GlaxoSmithKline, Jounce, Leap, Lilly, Seattle Genetics, and Merck; and has served on advisory board for Leap. Dr. Swain has consulted or advised for Cardinal Health, Daiichi-Sankyo, Genentech/Roche, Genomic Health, Inivata, Lily, Pieris Pharmaceuticals, and Tocagen; has received honoraria from Novartis and travel expenses from Caris Centers of Excellence, Daiichi-Sankyo, Genentech/Roche, Inivata, Lilly, and NanoString Technologies; has received institutional research funding from Genentech; and reported other relationships with AstraZeneca and Roche.