Aromatase inhibitors are generally not used to treat breast cancer in premenopausal women. Since most of the circulating estrogen is produced by the ovaries, not by conversion of androgens to estrogen, blocking the enzyme aromatase does not significantly decrease the production of estrogen. When aromatase inhibitors are used in premenopausal women, the decrease in estrogen activates the hypothalamus and pituitary axis to increase gonadotropin secretion, which in turn stimulates the ovary to increase androgen production. This counteracts the effect of the aromatase inhibitor.
An ongoing area of clinical research is optimizing adjuvant hormonal therapy in postmenopausal women with breast cancer. Tamoxifen has been standard treatment, however the ATAC trial has shown that clinical results are superior with an AI in postmenopausal women with localized breast cancer that is estrogen receptor positive. Further studies of various AIs are ongoing.
AIs have also been used experimentally in the treatment of adolescents whose predicted adult height is low.
Bodybuilders who take anabolic steroids may also take AIs to prevent the steroids from being converted to estrogen; an increase in estrogen levels has undesirable consequences for a bodybuilder, such as gynecomastia. This is often the case when a natural aromatase inhibitor 4-OHAD has itself been inhibited. 4-OHAD is a metabolite of testosterone, which can mean 4-OHAD remains inhibited whilst aromatase levels are allowed high.
In one recent study, aromatase inhibitors were found to be no more successful at treating pubertal gynecomastia than a placebo.
Aromatase inhibitors have also been shown to reverse age-related declines in testosterone, as well as primary hypogonadism.
Prospective study to assess short-term intra-articular and tenosynovial changes in the aromatase inhibitor-associated arthralgia syndrome.(Report)
Sep 01, 2008; Prospective study to assess short-term intra-articular and tenosynovial changes in the aromatase inhibitor-associated arthralgia...