Dr Kalinsky on Unmet Needs and Findings from RxPONDER in HR+/HER2– Breast Cancer

Kevin Kalinsky, MD, MS, professor, Department of Hematology and Medical Oncology, director, Division of Medical Oncology, Department of Hematology and Medical Oncology, Emory University School of Medicine; Louisa and Rand Glenn Family Chair in Breast Cancer Research, director, Glenn Family Breast Center, director, Breast Medical Oncology, Winship Cancer Institute of Emory University, discusses the correlation of serum anti-Müllerian hormone (AMH) levels in patients with premenopausal, hormone receptor (HR)–positive, HER2-negative, node-positive breast cancer and likelihood of these patients benefiting from adjuvant chemotherapy in the phase 3 SWOG S1007/RxPONDER trial (NCT01272037).

RxPONDER involved 5000 women with HR-positive, HER2-negative breast cancer who had 1 to 3 lymph nodes involved, Kalinsky begins. These women had Oncotype DX recurrence scores between 0 and 25 and were randomly assigned to receive either chemotherapy followed by endocrine therapy or endocrine therapy alone. The study’s primary observation was that premenopausal patients benefited from the addition of chemotherapy. However, there has been ongoing debate about how premenopausal status was defined in the trial, which led to further analysis to refine the group of patients who would benefit from the addition ofchemotherapy, he reports.

To address this, investigators launched an investigation into patients’ AMH levels and likelihood of benefiting from adjuvant chemotherapy, Kalinsky continues. The key finding from this analysis was that within the premenopausal group, patients with low AMH levels, who accounted for 20.6% of the population, did not benefit from chemotherapy. Low AMH levels were defined as those that were less than 10 picograms per milliliter by the traditional ELISA assay, he explains. Conversely, patients with medium or high AMH levels had significant benefits from chemotherapy, including a 7.8% improvement in invasive disease-free survival and a 4.4% improvement in distant relapse-free survival, Kalinsky notes.

Notably, low AMH levels were rare among younger patients, seen in only 2.9% of women under the age of 45 years, he explains. However, among women aged 50 to 54 years, 52.2% had low AMH levels. This study indicates that serum AMH levels could be a valuable tool in identifying which premenopausal patients are likely to benefit from chemotherapy, potentially leading to more personalized treatment strategies in this group, Kalinsky concludes.