SABCS 2023: Patient Age, Ovarian Function Suppression, and Endocrine Response

By: Chris Schimpf, BS
Posted: Monday, December 11, 2023

The addition of ovarian function suppression in patients with breast cancer receiving tamoxifen or aromatase inhibitors may improve patients’ response to preoperative endocrine therapy, according to the final screening results of the phase III ADAPTcycle trial, presented at the 2023 San Antonio Breast Cancer Symposium (SABCS; Abstract LBO1-05). Oleg Gluz, MD, of the West German Study Group and Hospital Bethesda in Moenchengladbach, Germany, and colleagues reported that assessing endocrine therapy response may prove useful in therapeutic decision-making, particularly in patients aged 50 and younger with early-stage breast cancers. In fact, they added, optimal response to preoperative endocrine therapy has the potential to eliminate the need for chemotherapy—especially among premenopausal patients.

A total of 4,334 patients were included in the multicenter trial, of whom 1,368 were aged 50 or younger and premenopausal, and 2,966 were older than age 50 or postmenopausal. Among the premenopausal patients, 23% received aromatase inhibitors plus ovarian function suppression, and 18.6% received tamoxifen plus ovarian function suppression. Among the postmenopausal patients, 86.5% received aromatase inhibitors.

The investigators reported that a response to endocrine therapy occurred in 48.2% of the premenopausal patients vs 72.7% of the postmenopausal participants (P < .001). Furthermore, they observed significant differences in response rates between the two groups with tamoxifen alone: 34.7% vs 46.4%, respectively. Among premenopausal patients, 55.7% responded to tamoxifen plus ovarian function suppression vs 76.4% with aromatase inhibitors plus ovarian function suppression, which was comparable to 76.8% among postmenopausal patients who received aromatase inhibitors. In addition, ovarian function suppression led to higher response rates to endocrine therapy in the small (n = 78) group of premenopausal patients who were older than 50. Finally, the investigators reported that even among patients with a recurrence score greater than 25, they observed a substantial response to aromatase inhibitors vs tamoxifen alone.

Disclosure: Dr. Gluz has received consulting fees from Roche, Novartis, Eli Lilly, MSD, Gilead Sciences, ExactScience, Agendia, Seagen, Daiichi Sankyo, Pfizer, and AstraZeneca.

2023 San Antonio Breast Cancer Symposium

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