Blood Biomarker AMH Predicts Chemotherapy Benefit in Premenopausal Women with HR-Positive Breast Cancer
核心洞察
Researchers identified anti-Müllerian hormone (搜索) (AMH) as a blood biomarker that more accurately predicts chemotherapy benefit than age or menopausal status in women under 55 with hormone receptor-positive, HER2-negative breast cancer.
In the RxPONDER trial analysis of 1,556 women, those with AMH levels ≥10 pg/mL saw a 54% reduction in invasive disease recurrence risk with chemotherapy (HR=0.46), while those below the threshold derived no benefit.
Approximately one in five premenopausal women had AMH levels low enough to potentially safely forgo chemotherapy and its associated toxicities.
A new analysis from the landmark RxPONDER clinical trial has identified anti-Müllerian hormone (搜索) (AMH), a blood biomarker of ovarian reserve, as a powerful predictor of which premenopausal women with hormone receptor-positive, HER2-negative breast cancer stand to benefit from adjuvant chemotherapy. Published in Annals of Oncology, the findings challenge decades of reliance on age and menstrual history to guide chemotherapy decisions.
The study analyzed blood samples from 1,556 women younger than 55 enrolled in the phase III RxPONDER trial, which originally demonstrated that many premenopausal women benefited from chemotherapy while postmenopausal women generally did not. The new analysis reveals that AMH levels provide a more biologically meaningful assessment of menopausal status than traditional clinical criteria.
"For decades we've relied primarily on age and menstrual history to determine menopausal status and in turn chemotherapy recommendations based on menopausal status," said senior author Andrew K. Godwin, Ph.D., deputy director of KU Cancer Center (搜索) and professor of pathology and laboratory medicine at KU Medical Center. "Our findings suggest that directly measuring ovarian reserve using ultrasensitive assays for AMH and Inhibin B (搜索) provides a much more biologically meaningful assessment."
Chemotherapy Benefit Tied to Ovarian Reserve
Among women with AMH levels of at least 10 picograms per milliliter—the cutoff for normal ovarian reserve—chemotherapy reduced the risk of invasive disease recurrence by more than half compared with endocrine therapy alone (hazard ratio [HR] = 0.46; 95% confidence interval [CI] = 0.33–0.65; adjusted P = .00012). This group represented 64% of the study population.
In stark contrast, the 36% of patients with low ovarian reserve—AMH below 10 pg/mL—showed no improvement from added chemotherapy in terms of invasive disease-free survival (HR = 1.27; 95% CI = 0.81–1.99; adjusted P = .47). A similar pattern emerged for distant relapse-free survival.
"Women whose ovaries are already approaching menopause appear unlikely to derive additional benefit from chemotherapy similar to what was noted in postmenopausal patients in RxPONDER," Godwin explained. Approximately one in five premenopausal women in the study had AMH levels low enough to suggest they could safely forgo chemotherapy.
AMH Outperforms Traditional Hormone Measures
Unlike commonly measured reproductive hormones such as estrogen, progesterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH), AMH remains relatively stable throughout the menstrual cycle. The study found that baseline serum levels of estradiol, progesterone, LH, and FSH were not associated with predictive potential for chemotherapy benefit. AMH, along with ultrasensitive inhibin B (搜索) (INHB) measured in the pg/mL range, independently predicted benefit.
"Menopausal status is an important decision-making consideration for adjuvant chemotherapy in patients with hormone-positive breast cancer," said Priyanka Sharma, M.D., professor of medical oncology at KU Medical Center and co-author of the study. "This analysis shows that, compared to other conventional methods, AMH is a much better measure to indicate which women are truly postmenopausal."
Toward Precision Medicine
Kevin Kalinsky, M.D., professor and division director of medical oncology at Emory University School of Medicine and principal investigator of RxPONDER, emphasized the clinical implications: "Rather than making treatment decisions based solely on age, we may soon be able to use objective biological measurements of menopausal status to identify who truly needs chemotherapy and who does not."
The laboratory analyses were performed at the Biomarker Discovery Laboratory at KU Medical Center using highly sensitive assays capable of detecting extremely low AMH and INHB concentrations not measurable by many routine clinical tests. The researchers noted that only a small number of clinical laboratories currently offer these ultrasensitive tests, and expanding availability will be critical as physicians incorporate them into standard care.
Limitations and Future Directions
In an accompanying editorial, Carmine Valenza, M.D., MPH, Ph.D.(c), and Ann H. Partridge, M.D., MPH, of Harvard Medical School and Dana-Farber Cancer Institute noted that the main limitation of the analysis was the very low use of luteinizing hormone-releasing hormone agonist (LHRHa)-based endocrine therapy in the RxPONDER trial, suggesting the findings are relevant specifically in the context of endocrine therapy with tamoxifen alone.
The researchers emphasize that prospective clinical trials are needed to further validate whether AMH measurements can guide treatment decisions. Two ongoing trials, OFSET and OPTIMA-Young, are exploring the use of LHRHa-based endocrine therapy in patients with breast cancer.
"Although future studies may further refine the optimal AMH and INHB thresholds, we believe that measuring ovarian reserve before treatment should become an important part of shared decision-making between physicians and patients," Godwin said. "Our goal is straightforward: to ensure that every woman receives the treatment she is most likely to benefit from while avoiding unnecessary chemotherapy and its associated toxicities."