High Levels of Fertility-Related Hormone May Be Linked to Increased Breast Cancer Risk
Having high levels of anti-Müllerian hormone (AMH)—a hormone that indicates the size of a woman’s ovarian reserve—before menopause may be associated with an increased risk of breast cancer, a study by Ge et al in the International Journal of Cancer found.
In a major study, leading scientists from the NYU School of Medicine analyzed blood samples from participants of ten cohort studies, including the Breast Cancer Now Generations Study at The Institute of Cancer Research, London, to examine the association of AMH levels with breast cancer risk.
The team examined blood samples from 5,957 premenopausal women from across the United States, the United Kingdom, Sweden, and Italy, and found that those in the quartile with the highest levels of AMH in their blood were 60% more likely to develop breast cancer—both before and after menopause—when compared to those in the lowest quartile.
AMH is produced in the ovaries, and blood levels of the hormone are commonly incorporated into fertility tests. High levels of the hormone indicate a larger ovarian reserve—the capacity of the ovaries to produce viable egg cells. AMH is a marker of time to menopause, with levels peaking between the ages of 20–25, before declining and becoming undetectable after menopause.
Those with higher AMH levels for their age tend to reach menopause later in life, which is itself known to be a risk factor for breast cancer, but the study found that AMH levels predict breast cancer risk even for cases of breast cancer that occur before menopause.
Study Findings
The team examined AMH levels in participants’ blood samples that had been collected prospectively, comparing those in the highest quartile (top 25%) for AMH levels with those in the lowest quartile (bottom 25%).
In the analysis of 2,835 participants with breast cancer and 3,122 controls of similar ages, higher levels of AMH were found to be significantly associated with an increase in breast cancer risk, with the trend being seen across the entire range of AMH levels.
Results were adjusted for potential confounding risk factors for breast cancer such as body mass index, how many children each woman had had, a family history of breast cancer, and age at menarche.
Looking at whether AMH levels were linked to risk of developing breast cancer of a certain subtype, the team found that those with the highest levels of AMH were 96% more likely to develop breast cancer that is susceptible to being driven by both estrogen and progesterone (estrogen receptor–positive, progesterone receptor–positive breast cancer) than those with the lowest levels of AMH.
Future Research
The team is now examining whether incorporating AMH levels into current risk prediction models could lead to improved prediction of breast cancer risk in premenopausal women.
It is hoped that being able to incorporate these hormone levels could help provide a more accurate indicator of risk for younger women, in particular to identify those at a higher risk of developing hormone-positive forms of breast cancer, providing women with more information on whether risk-reducing measures would be appropriate for them.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
