Research published in 2011 showed that Aromasin can lower risk in high-risk, postmenopausal women who've never been diagnosed with breast cancer. Aromasin is not approved by the FDA for this use, but doctors may consider it a good alternative to tamoxifen or Evista. In 2013, the American Society of Clinical Oncology (ASCO) released new guidelines on using hormonal therapy medicines to reduce breast cancer risk in high-risk women. These guidelines recommend that doctors talk to high-risk postmenopausal women about using Aromasin to reduce risk. ASCO is a national organization of oncologists and other cancer care providers. ASCO guidelines give doctors recommendations for treatments that are supported by much credible research and experience.
A number of investigators have reported on a rather rare syndrome of excess aromatase activity. In boys, it can lead to gynecomastia , and in girls to precocious puberty and gigantomastia . In both sexes, early epiphyseal closure leads to short stature. This condition is due to mutations in the CYP19A1 gene which encodes aromatase.  It is inherited in an autosomal dominant fashion.  It has been suggested that the pharaoh Akhenaten and other members of his family may have suffered from this disorder,  but more recent genetic tests suggest otherwise.  It is one of the causes of familial precocious puberty—a condition first described in 1937.