Is the risk of EPT substantially higher?
I found this article interesting, and I agree that women who have atypical hyperplasia should be counseled to consider the possible additional risk of hormone use. I didn’t see a reference, however, that supported this assertion: “Accordingly, the absolute risk of invasive breast cancer associated with use of estrogen-progestin menopausal hormone therapy (EPT) is also likely substantially higher than in average-risk women.”
Are there any high-quality studies that support this?
Adverse effects from agents that suppress estrogen levels
Are any studies being done to look at bazedoxifene in these patients alone or especially in combination with an estrogen? Encouraging the use of agents long term that profoundly suppress actual or effective estrogen levels, especially in young women, ignores the very profound adverse effects these agents can have both in the immediate and long term. I would be curious to know if there are any studies or recommendations regarding the use of gonadotropin agonists or antiandrogens in men older than age 35 to prevent prostate cancer.
Drs. Kaunitz and Samiian respond
We appreciate the thoughtful letters from Drs. Logan and Malick concerning our article on atypical hyperplasia (AH) of the breast. Regarding Dr. Logan’s question, we are not aware of any randomized controlled trials that have assessed the impact of EPT on the risk of being diagnosed with invasive breast cancer in women with a history of AH. An observational study looking at this issue did not distinguish between estrogen hormone therapy (ET) and EPT.1
However, we do know that in women at average risk for breast cancer, EPT increases the absolute risk of an invasive breast cancer by 1 additional case per 1,000 person- years of use.2 Accordingly, since women with a prior biopsy diagnosis of AH have a 4-fold elevated risk of being diagnosed with invasive breast cancer, it is reasonable to speculate that EPT would elevate this risk to some 4 additional cases per 1,000 person- years of use. This is why we recommend that women with a history of AH considering use of EPT be counseled regarding this potential elevated risk of being diagnosed with invasive breast cancer.
Regarding Dr. Malick’s questions, we are not aware of trials assessing the impact that bazedoxifene (with or without estrogen) has in women with a prior biopsy demonstrating AH. With respect to trials assessing androgen blockers in men to prevent prostate cancer, the Prostate Cancer Prevention Trial is assessing the use of finasteride in men aged 55 years and older.3